taxonID	type	description	language	source
03CF5E32FF8C53795F8E4C40FD90F96B.taxon	description	Rouse & Fauchald, 1997	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8C53795C5F4B3DFA68FA2B.taxon	diagnosis	Generic diagnosis (after Kupriyanova & Nishi, 2010). Tube white, opaque, circular in cross-section, keels and collar-like rings absent. Granular overlay may be present. Operculum a soft membranous vesicle without endplate borne on unmodified pinnulated radiole. Opercular constriction may be present. Pseudoperculum may be present on unmodified radiole. Radioles may be exceptionally flat ribbon-like. Arrangement of radioles in semi-circles (may be up to ¾ of a circle), maximum number up to 40 per lobe in larger species. Inter-radiolar membrane present. Radiolar eyes present. Stylodes absent. Mouth palps present. Seven thoracic chaetigerous segments. Collar trilobed or unlobed with smooth edge. Thoracic membrane long, forming ventral apron across anterior abdominal segments. Tonguelets between ventral and lateral collar lobes absent. Collar chaetae limbate, of two sizes (thus, in the classical terminology capillary and limbate), may exceptionally be supplemented by Apomatus chaetae. Apomatus chaetae usually present from chaetiger 3 onward. Thoracic uncini saw-to-rasp-shaped with approximately 30 teeth in profile, up to 3 (exceptionally 4) teeth in a row above and continuing onto peg; anterior peg very long, blunt, almost rectangular. Ventral thoracic triangular depression absent. Abdominal chaetae sickle-shaped with finely denticulate blades; uncini rasp-shaped with approximately 30 teeth in profile. Short achaetous anterior abdominal zone present. Posterior capillary chaetae present. Posterior glandular pad present.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8C53795F9E4E11FC10FE7D.taxon	diagnosis	Subfamily diagnosis. Tube not spirally coiled; body symmetrical; thoracic sickle (Apomatus) chaetae present; abdominal chaetae flat geniculate.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8C53795F9E4E11FC10FE7D.taxon	discussion	Remarks. The subfamily Filograninae was proposed by Rioja (1923: 107) who stated that presence of pinnules on the opercular peduncle “ indicates that the species included in this subfamily are very primitive, …, corroborated by a hardly developed operculum ”. However, molecular phylogenetic studies (e. g., Kupriyanova et al., 2006; Lehrke et al., 2007; Kupriyanova et al., 2023) found that both traditional subfamilies Serpulinae and Filograninae were not monophyletic, so Kupriyanova et al. (2023) re-classified and re-formulated the sub-family diagnoses and based these on chaetal structures.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8C537B5C984C8FFDAEFBE6.taxon	description	Fig. 2 A – G	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8C537B5C984C8FFDAEFBE6.taxon	materials_examined	Material examined. Holotype: W. 54373 (extraction number LK 287), Cocos (Keeling) Islands Territory, Muirfield Seamount (13 ° 14 ' 32 " S, 96 ° 17 ' 31 " E), depth 932 – 965 m, 21 / 10 / 2022. Paratypes: W. 53423 (LK 259), Christmas Island SW (10 ° 32 ' 59 " S, 105 ° 31 ' 59 " E), depth 1388 – 1533 m, 09 / 07 / 2021 (1 spec., radiolar crown missing, prepared for SEM); W. 54510 (LK 318), Cocos (Keeling) Islands Territory, Muirfield Seamount (13 ° 16 ' 41 " S, 96 ° 04 ' 06 " E), depth 1395 – 1459 m, 20 / 10 / 2022 (1 spec).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8C537B5C984C8FFDAEFBE6.taxon	description	Description. Tube: white opaque or slightly reddish, circular in cross section, attached to substrate throughout its length, with smooth surface, without either collar-like rings or flaring peristomes. Median keels absent (Fig. 2 A). Radioles: flat ribbon-like, wide (Fig. 2 A); each lobe with up to 12 pairs of radioles, arranged in semicircles, fused basally (connected by short inter-radiolar membrane) for about 1 / 20 of their length. Pinnules short and thin; each radiole ending into thin short filamentous tip (Fig. 2 A, not well visible here). Radiolar eyes not observed in the preserved material. Stylodes absent. Operculum: absent or lost (Fig. 2 A), no distinct peduncle observed. Pseudoperculum absent. Collar and thoracic membranes: collar unlobed, with entire edge, short, barely covering radiolar lobes (Fig. 2 A, B); continuous with wide thoracic membranes (Fig. 2 C, D) forming an apron across anterior abdominal chaetigers 1 or 2. Pairs of small, wart-like protuberances of collar chaetiger absent, calcium-secreting glands visible on collar. Thorax: with collar chaetiger and 6 uncinigerous chaetigers (Fig. 2 A, B). Uncinigerous tori positioned close to each other, ventral thoracic triangular depression absent. Collar chaetae (Fig. 2 B, D) simple capillary (limbate) of two sizes, Apomatus chaetae absent (Fig. 2 D). Subsequent chaetal bundles with Apomatus chaetae (Fig. 2 E) and simple capillary and limbate chaetae (Fig. 2 D). Uncini predominantly rasp-shaped (Fig. 2 C), with approximately 20 teeth in profile, 2 teeth in posterior-most row and up to 5 teeth in a row above and continuing onto peg; anterior peg long, blunt, almost rectangular (Fig. 2 C). Pair of prostomial eyes not observed. Abdomen: up to 40 abdominal chaetigers. Short achaetous anterior abdominal zone present. Uncini rasp-shaped with 3 – 6 rows of teeth and up to 25 teeth in profile view, long blunt almost rectangular peg (Fig. 2 F). Chaetae flat sickle-shaped with finely denticulate blades (Fig. 2 G). Long capillary chaetae in posterior chaetigers absent. Posterior glandular pad not observed. Size: body length (without radioles) up to 20 mm, width of thorax up to 0.8 mm. Radioles and operculum accounting for one third of entire length. Tube up to 1.2 mm wide with lumen of up to 1.0 mm diameter. Diagnostic remarks. The new species resembles Apomatus voightae Kupriyanova & Nishi, 2010 from the Patton-Murray seamounts (Gulf of Alaska) that differs from all other serpulid species by its very characteristic flat ribbon-like radioles. An unusual feature of A. voightae is the presence of Apomatus chaetae in the collar chaetae bundle. Normally in the genus Apomatus chaetae are present in abundance throughout most thoracic segments but are absent in the collar bundle (Kupriyanova & Nishi, 2010). Apomatus chaetae are absent in the collar bundle of Apomatus nishii n. sp. and an operculum is also lacking in this species, but soft vesicular opercula in this genus are easily lost, so this character is unreliable. Molecular data support monophyly of the genus Apomatus and placement of the new species in the genus. However, the relationship between the morphologically distinct species Apomatus voightae and A. nishii n. sp. need to be examined in further studies.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8C537B5C984C8FFDAEFBE6.taxon	etymology	Etymology. The species is named in honour of Professor Eijiroh Nishi (Yokohama National University, Japan) in recognition of his numerous important contributions to taxonomic and reproductive studies of Serpulidae.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8C537B5C984C8FFDAEFBE6.taxon	distribution	Distribution. Only known from seamounts off Christmas and Cocos (Keeling) Islands, 932 – 1533 m.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8E537B5FAE4DB8FC42FE33.taxon	type_taxon	Type species. Bathyvermilia challengeri Zibrowius, 1973 Generic diagnosis (after Kupriyanova & Ippolitov, 2015 emended). Tube white, opaque, circular to quadrangular in cross-section, keel (s) may present. Collar-like rings present. Operculum sub-globular, with simple flat to slightly conical chitinous endplate, sometimes encrusted by calcareous deposit. Peduncle cylindrical, either smooth or wrinkled, distal wings absent; inserted as 2 nd dorsal radiole on either side, constriction present. Pseudoperculum absent. Up to 35 radioles per lobe arranged in semi-circles. Inter-radiolar membrane, radiolar eyes, and stylodes absent. Mouth palps may present. Seven thoracic chaetigerous segments, six of which uncinigerous. Trilobed collar (may be not divided into lobes) with straight edge, tonguelets absent. Thoracic membranes of variable length, extending to 2 nd – 7 th thoracic segment. Collar chaetae limbate capillaries. Apomatus chaetae present. Thoracic uncini saw-shaped (rarely saw-to-rasp shaped), with 6 – 12 teeth and simple, pointed anterior fang. Abdominal chaetae flat narrow geniculate with blunt teeth. Anterior and mid-abdominal uncini saw-shaped, uncini on few far posterior segments rasp-shaped. Short achaetous anterior abdominal zone present. Posterior capillary chaetae present. Posterior glandular pad present.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8E537B5FAE4DB8FC42FE33.taxon	discussion	Remarks. Ten Hove and Kupriyanova (2009) listed five bathyal and abyssal species in this genus (Bathyvermilia challengeri, B. islandica Sanfilippo, 2001, B. kupriyanovae Bastida-Zavala, 2008, B. langerhansi (Fauvel, 1909), and B. zibrowiusi Kupriyanova, 1993 a). Kupriyanova and Nishi (2010) added a species from the Patton-Murray Seamount, Gulf of Alaska by transferring Vermiliopsis (?) eliasoni Zibrowius, 1970 to the genus Bathyvermilia. Further Kupriyanova and Ippolitov (2015) added Bathyvermilia gregrousei to the genus and emended the generic diagnosis to include the species with tetragonal, slightly spirally twisted tubes.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8E53745C704889FD0AF963.taxon	description	Fig. 3 A – F	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8E53745C704889FD0AF963.taxon	materials_examined	Material examined. W. 53395, Christmas Island SE (10 ° 33 ' 00 " S, 105 ° 42 ' 11 " E), depth 1225 – 1626 m, 06 / 07 / 2021 (1 spec. in tube, photo and prepared for SEM). Species diagnosis. Very recognisable tubes with characteristic sculpture made of numerous transverse ridges close to each other (Fig. 3 A). Thoracic membranes rounded, extending to 3 rd thoracic segment (Fig. 3 B). Operculum conical, covered with simple slightly raised chitinous endplate having distinct rims (Fig. 3 B). Peduncle smooth cylindrical, constriction obvious (Fig. 3 C). Collar chaetae simple limbate (Fig. 3 D). Apomatus chaetae present in thorax (Fig. 3 E). Thoracic uncini saw-to-rasp shaped, with 12 teeth in lateral view and simple, pointed anterior fang (Fig. 3 F).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8E53745C704889FD0AF963.taxon	discussion	Remarks. This species is easily recognisable by its very characteristic tube with numerous conspicuous transverse ridges (not anteriorly directed peristomes), positioned close to each other, encircling the tube interrupted by a longitudinal groove cutting transverse ridges near the base. The original records of this species came from three HMS “ Challenger ” stations in the North and South Pacific Ocean taken at 4246 – 5719 m (Zibrowius, 1973). Most recently a specimen was collected in the Eastern Australian Abyss (Gunton et al., 2021); this specimen was sequenced for the present study because DNA amplification of the B. challengeri specimen from IOT examined here was unsuccessful. The specimen of B. challengeri from IOT shows at least 12 teeth in lateral view of thoracic uncini, moreover, these uncini are saw-to-rasp shaped (Fig. 3 F). The original description of B. challengeri (Zibrowius, 1973) states “ thoracic uncini saw-shaped with about 7 to 10 teeth ”. The generic diagnosis in Kupriyanova and Ippolitov (2015) gives saw-shaped thoracic uncini with 6 – 10 teeth, while 9 – 11 teeth were reported for B. gregrousei. Thus, we emended the diagnosis of the genus Bathyvermilia to reflect the observed variability. The specimen collected off Johnston Atoll near Hawaii at 380 m (Kupriyanova et al., 2011) is currently the shallowest record for this nominal species. Although the specimen from the upper bathyal off Johnston Atoll fits the original description of B. challengeri and is morphologically very similar to the specimens collected from the lower abyssal zone, such a disjunct bathymetric distribution is unusual (reviewed in Capa et al., 2021). Further collecting and additional taxonomic studies of deep-sea serpulids are needed to determine whether B. challengeri does have disjunct or wide bathymetric distribution or whether at least two morphologically similar species are present in the Pacific Ocean.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8E53745C704889FD0AF963.taxon	distribution	Distribution. Mid-Pacific Ocean, 4246 – 5719 m, Johnston Atoll (about 1400 km west of Hawaii), 380 m; South Pacific Ocean off NSW, Australia, 2562 – 2587 m; South Indian Ocean, off Christmas Island, Australia, 1225 – 1626 m.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8153765FE24E35FECCFB8B.taxon	description	Fig. 4 A – H	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8153765FE24E35FECCFB8B.taxon	materials_examined	Material examined. Holotype: W. 53399 (LK 250), Christmas Island SE (10 ° 34 ' 13 " S, 105 41 ' 23 " E), depth 643 – 997 m, 06 / 07 / 2021. Paratypes: W. 53398 (LK 247), same as above (1 spec, photo and SEM); W. 54907 (1 spec).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8153765FE24E35FECCFB8B.taxon	description	Description. Tubes: white or slightly brownish, opaque, circular in internal in cross-section, more or less semicircular in external cross-section with attachment area narrowly wider than tube width (Fig 4 A, B), attached to substrate throughout their length. Tube surface with numerous (6 – 7) low keels and some occasional, slightly elevated peristomes (Fig. 4 A, B). Radioles: 10 – 11 pairs arranged in two semicircles. Inter-radiolar membrane and stylodes absent. Each radiole ending in a thick filamentous tip as long as pinnules. Peduncle: smooth circular in cross-section, slightly thicker than normal radioles and inserted as a 2 nd radiole. Operculum: semi-globular, with flat or slightly depressed chitinous endplate (Fig. 4 A, B). Constriction at junction of basal part of operculum and peduncle present. Pseudoperculum absent. Collar and thoracic membranes: collar trilobed, with ventral and two latero-dorsal lobes. Thoracic membranes continuing to thoracic chaetiger 5. Thorax: Seven thoracic segments, 6 with uncini (Fig. 4 C). Collar chaetae limbate of two sizes (Fig. 4 D). Rest of chaetae limbate plus Apomatus chaetae (Fig. 4 F). Thoracic tori positioned along mid-lateral line of thorax, triangular depression absent. Thoracic uncini saw-shaped with 8 – 9 teeth and pointed anterior fang (Fig. 4 E). Abdomen: with up to 60 chaetigers. Anterior abdominal chaetae flat narrow geniculate with blunt teeth (Fig. 4 G), replaced by capillary chaetae on posterior segments. Anterior abdominal uncini saw-shaped with 12 teeth and simple pointed fang (Fig. 4 H). Uncini of middle and posterior abdominal segments rasp-shaped, with up to 13 teeth in profile and 2 – 3 teeth per row. Short achaetous anterior abdominal zone present. Posterior glandular pad present. Size: total body length up to 15 mm, width of thorax up to 0.8 mm. Radioles and operculum accounting for one third of entire length. Tube up to 1.2 mm wide with lumen of up to 1.0 mm in diameter. Diagnostic remarks. The species in the genus are distinguished by tube structure, and to a lesser degree, by the length of the thoracic membranes and details of opercular structure. The new species is easily recognisable from all congeners by its characteristic tube with numerous low keels and occasional transverse ridges / peristomes. Tubes are also very distinct in B. challengeri (with numerous transverse ridges close to each other), B. eliasoni (with three longitudinal ridges raised into curved spines), B. gregrousei (tetragonal in cross-section, slightly spirally twisted) and B. langerhansi (with smooth shiny surface, sub-triangular in cross-section with a median keel, but lacking lateral keels, peristomes, and transverse ridges). Bathyvermilia islandica, B. kupriyanovae and B. zibrowiusi are similar in having tubes circular in cross-section, with smooth shiny surface and distal peristomes. The tube of B. islandica is attached to the substrate for all its length, forming a distinct peripheral basal flange and undulated peristomes are sometimes present along the tube but are rare. Bathyvermilia islandica is also distinct in having long thoracic membranes ending at the 7 th thoracic chaetiger, they are wide up to the 2 nd segment, and then narrow sharply. Bathyvermilia zibrowiusi is most similar to B. kupriyanovae as both species have tubes with wide peristomes and thoracic membranes extending to the 4 th chaetiger. The main difference between them is the opercular endplate with developed concentric ridges in B. zibrowiusi, as opposed to simple chitinous endplate with some calcareous inclusions in B. kupriyanovae. The molecular results of this study did not support monophyly of the genus Bathyvermilia; alternatively, the data suggest that the new species does not belong to the genus Bathyvermilia. However, because morphology of Bathyvermilia rolandobastidai n. sp. fits the generic diagnosis of the genus Bathyvermilia well, we decided against the change in nomenclature until further molecular data become available.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8153765FE24E35FECCFB8B.taxon	distribution	Distribution. Only known off Christmas Island, South Indian Ocean, 643 – 997 m.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8153765FE24E35FECCFB8B.taxon	etymology	Etymology. The species is named after Professor Rolando Bastida-Zavala (Universidad de Mar, Oaxaca, Mexico) to honour his important contributions to taxonomic studies of Serpulidae.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8353765FC64D6EFABFFB89.taxon	type_taxon	Type species. Bathyvermilioides juliebrockae n. sp. Generic diagnosis. Tube white, opaque, tusk-shaped, quadrangular in cross-section, without peristomes. Operculum very hard, semi-globular shiny endplate. Peduncle cylindrical, smooth, without wings; inserted as 2 nd dorsal radiole on one side. Pseudoperculum absent. Radioles arranged in semi-circles, up to 12 per lobe. Inter-radiolar membrane and stylodes absent. Radiolar eyes and mouth palps absent. Seven thoracic chaetigerous segments. Collar trilobed, with entire edge, continuous with short thoracic membranes ending at 2 nd thoracic chaetiger. Tonguelets absent. Collar chaetae limbate. Apomatus chaetae present. Thoracic uncini saw-shaped with 9 – 10 teeth in profile, anterior fang pointed. Triangular depression absent. Abdominal chaetae short, flat triangular with wide distal denticulate blade; abdominal uncini rasp-shaped, anterior fang pointed. Achaetous anterior abdominal zone absent. Long posterior capillary chaetae absent. Posterior glandular pad absent.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8353765FC64D6EFABFFB89.taxon	discussion	Remarks. The new genus Bathyvermilioides has tusk-shaped quadrangular in cross-section tubes resembling those of nominal Bathyditrupa and Spirodiscus, but the similarities end here, and quadrangular tubes are apparently convergent in several genera of deep-sea serpulids (Kupriyanova & Ippolitov, 2015). The genus clearly belongs to the subfamily Filograninae as indicated by the presence of the thoracic Apomatus chaetae and flat geniculate abdominal chaetae and which is supported by molecular results here (Fig. 1). The results of the phylogenetic analysis here (Fig. 1) showed that the new taxon does not fall into the Bathyvermilia clade (type species B. challengeri) but belongs to the well supported clade with Rhodopsis pusilla, Semivermilia, and Pseudovermilia. The phylogenetic position of B. juliebrockae n. gen., n. sp. suggests that the new taxon could have been included in the genus Rhodopsis. However, the taxa are very different morphologically, as the two currently valid species of the genus Rhodopsis are tiny, with the tubes <0.2 mm in diameter and often bearing unpaired brood chambers. The operculum in Rhodopsis is usually covered with a well-developed soft chitinous endplate bearing spines, the number of thoracic chaetigerous segments varies from four to six, and the achaetous anterior abdominal zone is long. Chaetal characters also differ in the two taxa as in Rhodopsis collar chaetae are absent, both thoracic and abdominal uncini are rasp-shaped, and abdominal chaetae are flat narrow geniculate. Morphologically the new species most closely resembles Bathyvermilia gregrousei, a deep-sea species inhabiting similarly quadrangular, although smaller and slightly spirally twisted, tubes. It is likely that the Bathyvermilia gregrousei also should be transferred to the new genus, but molecular data are needed to confirm this hypothesis. Because of these morphological similarities with Bathyvermilia and phylogenetic position of the new species we established the new genus Bathyvermilioides. The suffix - oides means “ similar to ”. This taxonomical decision will again be tested in future molecular studies of deep-sea serpulids.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8353705C464D6BFE63FB56.taxon	description	Fig. 5 A – L	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8353705C464D6BFE63FB56.taxon	materials_examined	Material examined. Holotype: W. 54380, Cocos (Keeling) Islands Territory, Investigator Ridge Abyssal (11 ° 15 ' 26 " S, 97 ° 58 ' 08 " E), depth 4980 – 4990 m, 12 / 10 / 2022 (not removed from the tube). Paratype: W. 55302 (LK 319), same as above (specimen removed for DNA, photos, and SEM).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8353705C464D6BFE63FB56.taxon	description	Description. Tube: white opaque, ostensibly free, with shiny surface, tusk-shaped, thick-walled, mostly quadrangular in cross-section, edges rounded and never denticulate (Fig. 5 A). Radiolar crown: with 11 pairs of radioles in holotype, arranged pectinately, easily detachable from short radiolar lobes. Inter-radiolar membrane and stylodes absent. Terminal filaments of radioles thin, spirally twisted. Radiolar eyes and mouth palps not observed. Peduncle: smooth, cylindrical, slightly thicker than remaining radioles, distal wings absent; inserted on left side between base of 1 st and 2 nd radioles. Collar and thoracic membranes: collar covering bases of radiolar lobes, thin; four-lobed, with ventral lobe made of two lobes and distinctly higher than lateral ones (Fig. 5 B – D). Collar continuous with short rounded thoracic membranes ending at 2 nd chaetiger (Fig. 5 E). Operculum: with soft membranous semi-transparent ampulla and distal part distinctly differentiated from basal part. Distally operculum covered with very hard, brownish semi-globular endplate with shiny surface (Fig. 5 F); conspicuous constriction between operculum and peduncle present (Fig. 5 F). Pseudoperculum absent. Thorax: with 7 chaetigerous segments, 6 of which uncinigerous (Fig. 5 B – D). Small bundle of limbate collar chaetae. Subsequent chaetae limbate, of two sizes, Apomatus chaetae present (Fig. 5 G, H, e. g., the strongly bent chaeta). Uncini saw-shaped, with 9 – 10 teeth in profile view and pointed anterior fang (Fig. 5 J). Pair of prostomial eyes absent. Triangular depression absent (Fig. 5 C), thoracic tori widely separated and almost parallel to mid-lateral line of thorax. Abdomen: paratype with 56 segments. Abdominal chaetae short, flat triangular with wide distal denticulate blade (Fig. 5 L). Long capillary chaetae absent in posterior chaetigers (Fig. 5 I). Uncini rasp-shaped with 9 – 10 teeth in profile and up to 5 rows of teeth above pointed anterior fang (Fig. 5 K). Achaetous anterior abdominal zone absent. Size: total body length of paratype 13.8 mm, including 4.4 mm long radioles, 4.0 mm long thorax, 5.4 mm long abdomen, width of thorax 1.1 mm. Complete tube of holotype 22 mm long (Fig. 5 A). In holotype external tube diameter of tube mouth 1.5 mm, corresponding lumen diameter 1.1 mm. Species diagnosis. The species is characterised by distinct quadrangular tusk-shaped tubes and the operculum covered with a very hard (questionably calcified) convex (semi-globular) brown endplate. This very hard endplate distinguishes the new species from other quadrangular-tubed taxa that have soft endplates. The diameter of the open posterior end suggests that the specimen originally settled on a small pebble or even a sand granule, and later broke free.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8353705C464D6BFE63FB56.taxon	distribution	Distribution. Only known from seamounts off Cocos (Keeling) Islands, Indian Ocean, 4980 – 4990 m.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8353705C464D6BFE63FB56.taxon	etymology	Etymology. The abyssal species is named in honour of Professor Julie Brock (University of Hawaii at Manoa, USA) for her numerous and important contributions to taxonomy of deep-sea serpulids.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8553705FFF4C08FB8DFDAB.taxon	type_taxon	Type species. Filogranula gracilis Langerhans, 1884 Generic diagnosis (from ten Hove & Kupriyanova, 2009). Tube white, opaque, with elaborate peristomes; keel present. Granular overlay absent. Operculum with chitinous endplate, may have additional spines in the centre. Peduncle cylindrical, smooth, without wings; inserted as 2 nd dorsal radiole on one side. Pseudoperculum absent. Radioles arranged in semi-circles, up to 7 per lobe. Inter-radiolar membrane and stylodes absent. Radiolar eyes may be present. Mouth palps not observed. Seven thoracic chaetigerous segments. Collar generally non-lobed (may be trilobed) with entire edge, continuous with short thoracic membranes ending at 2 nd thoracic chaetiger. Tonguelets absent. Collar chaetae fin-and-blade and limbate. Apomatus chaetae present. Thoracic uncini saw- or saw-to-rasp-shaped with 12 – 14 teeth in profile, up to 5 teeth in a row above anterior peg, blunt, gouged underneath. Triangular depression absent. Abdominal chaetae short, flat triangular with wide distal denticulate blade; abdominal uncini rasp-shaped. Achaetous anterior abdominal zone present. Long posterior capillary chaetae present. Posterior glandular pad absent.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8553705FFF4C08FB8DFDAB.taxon	discussion	Remarks. Zibrowius (1983) and Kupriyanova (1993 b) noticed that the genera Chitinopoma Levinsen, 1884 and Filogranula are very similar in general opercular and chaetal structure, as well as in the length of thoracic membranes. Ten Hove and Kupriyanova (2009) mentioned that additional studies are needed to determine whether these two genera should be synonymised. The most recent multigene molecular phylogeny of Kupriyanova et al. (2023) showed that F. stellata and C. serrula are sister groups, thus supporting the hypothesis.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8553715CBB4B19FE86F9E2.taxon	description	Fig. 6 A – F	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8553715CBB4B19FE86F9E2.taxon	description	Filogranula cf. stellata – Kupriyanova et al., 2011: 52, fig. 5 J (tube only, RV “ Vityaz ” Stn. 6348 - 2, Pacific Ocean, 18 º 35 ' N, 175 º 05 ' W, 1600 – 1900 m).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8553715CBB4B19FE86F9E2.taxon	materials_examined	Material examined. W. 53461, Territory of Christmas Island, Clara Marie Seamount (13 ° 34 ' 35 " S, 105 ° 19 ' 39 " E), depth 2189 – 2264 m, 12 / 07 / 2021 (1 tube); W. 53462 (LK 257), same as above (1 spec.); W. 53403 (LK 261), Christmas Island SE (10 ° 33 ' 22 " S, 105 ° 45 ' 51 " E), depth 3200 – 3345 m, 07 / 07 / 2021 (1 spec.); W. 53407 (LK 269), same as above (1 spec.); W. 54390 (LK 280), Cocos (Keeling) Islands Territory (12 ° 13 ' 32 " S, 96 ° 57 ' 36 " E), depth 1113 – 1343 m, 17 / 10 / 2022 (1 spec. prepared for SEM). Species diagnosis. Tube white, opaque, with elaborate star-like peristomes; denticulate keel present (Fig. 6 A). Operculum with chitinous concave endplate (Fig. 6 A, C). Peduncle smooth cylindrical, without wings, gradually continuing into operculum without constriction (Fig. 6 C), inserted as 2 nd dorsal radiole on one side. Seven thoracic chaetigerous segments (Fig. 6 C). Collar non-lobed with entire edge, continuous with short thoracic membranes, ending at 2 nd thoracic chaetiger (Fig. 6 D). Collar chaetae fin-and-blade and limbate (Fig. 6 F). Apomatus chaetae present (Fig. 6 E). Illustrations of uncini and abdominal chaetae are given by ten Hove and Kupriyanova (2009, fig. 19).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8553715CBB4B19FE86F9E2.taxon	discussion	Remarks. This species with very characteristic tubes bearing denticulate collars was originally described from the Northern Atlantic. Kupriyanova et al. (2011) provided the first (tentative as based on an empty tube only) record of the species from the Pacific Ocean. Most recently, the molecular phylogeny of Kupriyanova et al. (2023) included sequences of a specimen from Lost City Hydrothermal field located on Mid-Atlantic Ridge (Table 1). This study provided the first record of the species from the Indian Ocean. The phylogenetic results of this study support placement of the collected specimens into Filogranula stellata.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8553715CBB4B19FE86F9E2.taxon	distribution	Distribution. North Atlantic Ocean, 320 – 1775 m; Mediterranean, 700 – 2485 m; Pacific Ocean, 1600 – 1900 m; Indian Ocean, Territories of Christmas and Cocos (Keeling) Islands, 1113 – 3345 m.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF8453725FC64FBBFCEFF8BB.taxon	type_taxon	Type species. Protis simplex Ehlers, 1887 Generic diagnosis (from Rzhavsky et al., 2013 emended). Tube white, opaque, without peristomes, keel present in P. akvaplani. Operculum absent or one or more membranous globular opercula present on normal pinnulate radiole (s). Arrangement of radioles pectinate, up to 20 per lobe. Inter-radiolar membrane absent. Radiolar eyes not observed. Stylodes absent. Mouth palps absent. Seven (six in P. akvaplani) thoracic chaetigers. Collar trilobed with entire edge, tonguelets absent. Thoracic membranes variable, ending at chaetiger 3 in P. akvaplani and in P. melmackenzieae n. sp. or long, at least to end of thorax and usually forming ventral apron across anterior abdominal segments. Collar chaetae fin-and-blade and limbate. Apomatus chaetae present. Thoracic uncini saw-shaped with about 6 (up to 12 in P. melmackenzieae n. sp.) teeth, anterior fang simple pointed. Triangular depression absent. Abdominal chaetae flat narrow geniculate with rounded teeth, slightly more triangular blade in P. hydrothermica. Abdominal uncini rasp-shaped in all segments or saw-shaped in anterior segments, with up to 6 teeth in profile, approximately 5 – 7 teeth in a row above fang. Achaetous anterior abdominal zone absent. Long posterior capillary chaetae present. A posterior glandular pad may be present. Remarks. Ehlers’ original diagnosis does not mention an operculum at all, the lack of an operculum thus was considered a characteristic feature of Protis. Kupriyanova and Jirkov (1997) extended the diagnosis to include individuals with one or more opercula, following the description of the abyssal P. polyoperculata by Kupriyanova (1993 a). Rzhavsky et al. (2013) emended the diagnosis to include their newly described P. akvaplani, having tubes with a very distinct high keel and six thoracic segments. Here we further emended the diagnosis to reflect the short thoracic membranes in P. akvaplani and P. melmackenzieae n. sp.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF87536C5C9A4CF0FCFBFC83.taxon	description	Fig. 7 A – F, 8 A – F	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF87536C5C9A4CF0FCFBFC83.taxon	materials_examined	Material examined. Holotype: W. 54485, Cocos (Keeling) Islands Territory, Cocos (Keeling) (12 ° 13 ' 32 " S, 96 ° 57 ' 36 " E), depth 1113 – 1343 m, 17 / 10 / 2022, complete specimen with operculum. Paratypes: W. 53456 (LK 248), Territory of Christmas Island, Karma Seamount (12 ° 49 ' 33 " S, 107 ° 02 ' 48 " E), depth 2760 – 2850 m, 11 / 07 / 2021 (1 spec. prepared for SEM); W. 55294 (LK 274), Cocos (Keeling) Islands Territory, Rudist Seamount (11 ° 03 ' 47 " S, 99 ° 26 ' 36 " E), depth 3780 – 3839 m, 12 / 10 / 2022 (1 spec.); W. 55299 (LK 309), same locality (1 spec); W. 55298 (LK 310), same locality (1 spec.); W. 54414 (LK 305), same locality (1 spec.); W. 55291 (LK 306), same locality (1 spec.); W. 54415 (LK 298), same locality (1 spec.).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF87536C5C9A4CF0FCFBFC83.taxon	description	Description. Tube: pink, although tube colour ranging from nearly white, only slightly pinkish to distinctly pink (Fig. 7 A – F), entirely opaque, circular in cross section, attached to substrate throughout its length (Fig. 7 A – F). Tube surface rough (not smooth), with growth ridges and occasional narrow peristomes; with attachment area narrowly wider than tube width. Radioles: each lobe bearing 8 – 10 radioles arranged pectinately, not connected by inter-radiolar membrane (Fig. 8 B). Radiolar eyes and distinct long terminal pinnules absent. Operculum: if present, a membranous transparent globular vesicle with slightly differentiated distal endplate (Fig. 8 A, B) on a normally pinnulated left 2 nd radiole. Pseudoperculum absent. Collar and thoracic membranes: collar with entire edge, short, barely covering radiolar lobes. Trilobed, medio-ventral lobe slightly higher and wider than lateral lobes (Fig. 8 B, C); collar continuous with short thoracic membranes ending as rounded flaps at 3 rd thoracic segment, no apron (Fig. 8 D). Pairs of small, wart-like protuberances of collar chaetiger absent; tonguelets between ventral and lateral collar parts absent. Thorax: with collar chaetiger and 6 uncinigerous chaetigers (Fig. 8 B, C). Collar chaetae limbate and fin-and-blade, distal blade not separated from proximal dentate zone (Fig. 8 E). Subsequent chaetae limbate, of two sizes. Apomatus chaetae present in posterior thoracic segments (Fig. 8 F). Uncini along entire thorax saw-shaped, with 5 – 6 slightly curved teeth and simple pointed fang (Fig. 8 H). Prostomial eyes not observed. Abdomen: up to 40 abdominal chaetigers. Achaetous anterior abdominal zone absent. Anterior uncini saw-shaped, with 7 – 8 teeth in profile and simple pointed fang (Fig. 8 I), posterior rasp-shaped. Abdominal chaetae flat narrow geniculate with rounded teeth and tapered tip (Fig. 8 G). Long capillary chaetae of posterior chaetigers not observed. Posterior glandular pad present. Size: total body length up to 14 mm, including up to 4.0 mm long radioles, 3.2 mm long thorax 6.8 mm long abdomen, width of thorax 0.6 mm. In holotype external diameter of tube mouth 1.2 mm, corresponding lumen diameter 1.0 mm. Species diagnosis. The new species is clearly different from the rest of the genus Protis due to the distinctly pinkish tube. This is one of the first newly described species (along with H. perneti n. sp.) of the genus in which a detailed illustrated description is accompanied by the molecular sequence data from the type series.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF87536C5C9A4CF0FCFBFC83.taxon	etymology	Etymology. The species is named after Melanie Mackenzie, collection manager at Museums Victoria, Melbourne, Australia.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF87536C5C9A4CF0FCFBFC83.taxon	distribution	Distribution. Only known from seamounts off Christmas and Cocos (Keeling) Islands, Indian Ocean, 1113 – 3839 m.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF99536D5E674A57FD00F8CB.taxon	description	Fig. 9 A – G	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF99536D5E674A57FD00F8CB.taxon	materials_examined	Material examined. Holotype: W. 53467 (LK 268), Territory of Christmas Island, Apollo Seamount (11 ° 24 ' 45 " S, 104 ° 56 ' 32 " E), depth 1285 – 1350 m, 13 / 07 / 2021 (prepared for SEM). Paratypes: W. 53480 (LK 254), Territory of Christmas Island, Balthazar Seamount (11 ° 24 ' 16 " S, 104 ° 26 ' 25 " E), depth 1237 – 1290 m, 16 / 07 / 2021 (1 spec.); W. 53482 (LK 270), same locality (1 spec.); W. 54384 (LK 303), Cocos (Keeling) IslandsTerritory (11 ° 49 ' 56 " S, 96 ° 37 ' 36 " E), depth 1589 – 1896 m, 14 / 10 / 2022 (1 spec.); W. 54408 (LK 300), Cocos (Keeling) Islands Territory, Muirfield Seamount (13 ° 16 ' 41 " S, 96 ° 04 ' 06 " E), depth 1459 – 1595 m, 20 / 10 / 2022 (1 spec.).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF99536D5E674A57FD00F8CB.taxon	description	Description. Tube: white or slightly brownish, entirely opaque, circular in cross section, attached to substrate throughout its length. Tube surface with some growth lines, but without distinct ridges and peristomes (Fig. 9 a). Radioles: each lobe bearing 8 – 10 radioles arranged pectinately, not connected by an inter-radiolar membrane (Fig. 9 A). Radiolar eyes and distinct long terminal pinnules absent. Operculum: absent or lost in examined specimens (Fig. 9 A). Collar and thoracic membranes: collar with entire edge, short, barely covering radiolar lobes. Trilobed, medio-ventral lobe slightly higher and wider than lateral lobes (Fig. 9 B, C); collar continuous with long thoracic membranes ending as long apron (Fig. 9 B, C). Pairs of small, wart-like protuberances of collar chaetiger absent; tonguelets between ventral and lateral collar parts absent. Thorax: with collar chaetiger and 6 uncinigerous chaetigers (Fig. 9 A – C). Collar chaetae limbate and fin-and-blade, distal blade well separated from proximal dentate zone (Fig. 9 E). Subsequent chaetae simple limbate, of two sizes. Apomatus chaetae present in posterior thoracic segments (Fig. 9 F). Uncini along entire thorax saw-shaped, with 5 – 6 slightly curved teeth and simple pointed fang (Fig. 9 D). Prostomial eyes not observed. Abdomen: up to 40 abdominal chaetigers. Achaetous anterior abdominal zone absent. Uncini rasp-shaped, with 3 - 4 teeth in a row, 7 – 8 teeth in profile and simple pointed fang (Fig. 9 G). Abdominal chaetae flat narrow geniculate with rounded teeth and tapered tip (Fig. 9 H). Distinct long capillary chaetae of posterior chaetigers present. Posterior glandular pad not observed. Size: total length up to 9.4 mm, including up to 3.6 mm long radioles, 2.8 mm long thorax, 3.0 mm long abdomen, width of thorax 0.9 mm. In holotype external diameter of tube mouth 1.2 mm, corresponding lumen diameter 1.0 mm. Diagnostic remarks. According to World Register of Marine Species (Read & Fauchald, 2024), the genus Protis contains seven poorly known species mainly from bathyal and abyssal locations. The taxonomy of the genus is problematic because the chaetae, uncini, and tubes are very similar and opercula, if present, are normally undifferentiated membranous vesicles. Both operculate and non-operculate species are described, however, soft vesicular opercula are easily lost. Moreover, Protis arctica (Hansen, 1879) and P. polyoperculata Kupriyanova, 1993 a have been reported to contain both operculate and non-operculate specimens (Kupriyanova, 1993 a; Ben-Eliahu & Fiege, 1996; Kupriyanova & Jirkov, 1997). Protis hydrothermica ten Hove & Zibrowius, 1986 shows two characters not known for the other species: warts between ventral and lateral collar lobes and a pair of pockets in the medio-ventral collar. Protis akvaplani Rzhavsky et al., 2013 shows very distinct characters: it has only six thoracic chaetigerous segments, short thoracic membranes ending after the 3 rd thoracic chaetiger, and tube with a high longitudinal keel. Protis melmackenzieae n. sp. differs from all other species of the genus by very distinct pink tubes. Protis pacifica Moore, 1923 of Southern California (below 500 m) is recognisable because of its large size (body size up to 65 mm long). However, distinguishing Protis simplex Ehlers, 1887 and P. brownii (Pixell, 1913) from P. perneti n. sp. is not straightforward because descriptions of the former two taxa are brief and generic, lacking indications of obvious diagnostic characters. Moreover, P. browni from Antarctica was even suggested as a possible synonym of P. simplex from the bathyal off Florida (ten Hove & Kupriyanova, 2009). There are two obvious morphological differences between P. melmackenzieae n. sp. and P. perneti n. sp. First, the thoracic membranes are short ending at chaetiger 3 in the former but are with very long apron in the latter. Second, the distal blade of special collar chaetae is not separated from proximal dentate fin in P. melmackenzieae n. sp. versus very well separated in almost bayonet-like special collar chaetae of P. perneti n. sp. With this in mind, we described here Protis perneti n. sp. as a species distinct from both nominal P. brownii and P. simplex mostly based on geographical information. This taxonomical decision will be tested in future molecular studies of deep-sea serpulids. This is one of the first newly described species of the genus in which a detailed illustrated description is accompanied by the molecular sequence data from the type series. The results of the phylogenetic analysis (Fig. 1) suggest that one of the terminals of P. perneti n. sp. is more closely related to Protis hydrothermica. Clearly, the relationships between these taxa need to be examined in further studies when additional specimens of the former species become available.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF99536D5E674A57FD00F8CB.taxon	etymology	Etymology. The species is named after Professor Bruno Pernet (California State University at Long Beach, California, USA) for his important contributions to serpulid larval ecology and evolution.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF99536D5E674A57FD00F8CB.taxon	distribution	Distribution. Only known from seamounts off Christmas and Cocos (Keeling) Islands, Indian Ocean, 1237 – 1896 m.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF98536D5C1C4CD5FC24F96D.taxon	diagnosis	Subfamily diagnosis. Tube not spirally coiled, body symmetrical; thoracic sickle (Apomatus) chaetae absent; abdominal chaetae either true trumpet-shaped or flat trumpet-shaped.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF98536E5C0B4FCDFA57FC03.taxon	diagnosis	Tribe diagnosis. Tube not spirally coiled; body symmetrical; thoracic sickle (Apomatus) chaetae always absent; abdominal chaetae true trumpet-shaped.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF98536E5C0B4FCDFA57FC03.taxon	type_taxon	Type species. Hyalopomatus claparedii Marenzeller, 1878 Generic diagnosis (after Kupriyanova & Ippolitov, 2015). Tube white, opaque, sometimes with external hyaline layer; (semi) circular or quadrangular with rounded edges in cross-section. Tabulae may be present. Operculum globular, soft, without distinct endplate or consisting of proximal ampulla with slightly chitinized distal cap; conspicuous constriction between operculum and peduncle; sometimes operculum absent. Peduncle thin (same thickness as radioles), cylindrical, smooth, wings absent; inserted outside radiolar crown proper in front of 1 st dorsal radiole on either side or between base of 1 st and 2 nd radioles. Pseudoperculum absent. Up to 15 pairs of radioles, in pectinate arrangement. Inter-radiolar membrane absent. Radiolar eyes rarely present. Stylodes absent. Mouth palps present. Six thoracic chaetigerous segments, 5 of which uncinigerous. Collar trilobed, tonguelets between ventral and lateral collar lobes absent. Thoracic membranes short, ending at 1 st or 2 nd chaetiger. Collar chaetae simple limbate capillaries and fin-and-blade, with or without gap between fin and blade. Apomatus chaetae absent. Thoracic uncini rasp-shaped with about 20 small teeth in profile view, up to 9 teeth in a transverse row above flat or slightly gouged anterior peg, made of two or more rounded lobes with shallow incision (s) in between. Triangular depression absent. Abdominal chaetae ending in long narrow tip made of pointed teeth that at least partly arranged in two rows on anterior and mid-abdominal segments. Long capillaries on posterior chaetigers. Abdominal uncini rasp-shaped, similar to thoracic ones, but their anterior peg with 3 – 6 flat rounded lobes. Achaetous anterior abdominal zone may be present. Posterior glandular pad absent.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF98536E5C0B4FCDFA57FC03.taxon	discussion	Remarks: The genus Hyalopomatus currently contains 14 nominal species mainly from bathyal and abyssal depths (ten Hove & Kupriyanova, 2009; Kupriyanova et al., 2011, Kupriyanova & Ippolitov, 2015). Likely because of the deep-sea habitat, these animals are poorly known. In fact, six (Hyalopomatus cancerum Knight-Jones et al., 1997; H. dieteri Kupriyanova & Ippolitov, 2015; H. langerhansi Ehlers, 1887; H. nigropileatus Ehlers, 1900; H. macintoshi Gravier, 1911; and H. sombrerianus (McIntosh, 1885 )) out of 14 currently valid species are known only by few specimens. Morphologically, the species of Hyalopomatus are characterized by six thoracic chaetigers, short thoracic membranes, vesicular opercula on thin non-pinnulated peduncle, fin-and-blade special collar chaetae and, most importantly, uncini with very distinct flat crenulated pegs. A smooth tube with a breaking point (likely a former peristome) (as in Fig. 12 A) appears to be characteristic for the genus Hyalopomatus as such breaks are frequently illustrated (e. g., Hyalopomatus biformis, H. claparedii, H. madreporae, H. marenzelleri, and H. variorugosus). While the species of the genus are relatively easily distinguishable from representatives of other serpulid genera, the species within this genus tend to be morphologically similar to each other. The distinct species are Hyalopomatus madreporae Sanfilippo, 2009 and H. cancerum that lack opercula. Tube structure provides further characters to distinguish species within this genus: H. dieteri has characteristic quadrangular in cross-section tubes, tube surface of H. variorugosus is distinctly rugose because of characteristic minute flap-like structures, while the attached part of the H. biformis (Hartman, 1960) tube has a high keel (Bastida-Zavala, 2008) and tubes of H. langerhansi have slight lateral keels in the part attached to the substrate (Zibrowius, 1969). The remaining 8 species have simple circular in cross-section tubes with smooth surface and differ by the details of opercular morphology, length of thoracic membranes, and collar structure. See remarks to new species described below. Kupriyanova et al. (2010) emended the diagnosis of the genus Hyalopomatus because SEM of the abdominal chaetae of H. cf. mironovi Kupriyanova, 1993 c revealed that their tips have the teeth arranged in two rows, at least at the base of the chaetal tip and are not “ flat narrow geniculate with pointed teeth ”. Thus, the abdominal chaetae appear to be a variation of true trumpet-shaped (sensu ten Hove & Kupriyanova, 2009) chaetae normally characterised by two rows of denticles separated by a hollow groove and extended into a long lateral spine. The tips of abdominal chaetae in H. biformis are similarly not flat but are arranged into at least two irregular rows (Kupriyanova & Nishi, 2010, fig. 6 C), and these tips are clearly true trumpet-shaped in H. dieteri (Kupriyanova & Ippolitov, 2015, fig. 12 H). This type of abdominal chaetae is typical for representatives of tribe Ficopomatinae, which is also supported by molecular sequence data here (Fig. 1) and in Kupriyanova et al. (2023).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9B536B5CA84AD6FB4CF8D3.taxon	description	Fig. 10 A – I	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9B536B5CA84AD6FB4CF8D3.taxon	materials_examined	Material examined. Holotype: W. 55296 (LK 302), Cocos (Keeling) Islands Territory, Rudist Seamount (11 ° 03 ' 47 " S, 99 ° 26 ' 36 " E), depth 3780 – 3839 m, 12 / 10 / 2022 (specimen with operculum in tube). Paratypes: W. 53396 (LK 252), Christmas Island SE (10 ° 33 ' 00 " S, 105 ° 42 ' 11 " E), depth 1225 – 1626 m, 06 / 07 / 2021 (1 spec.); W. 55297 (LK 288), Cocos (Keeling) Islands Territory, Muirfield Seamount (13 ° 14 ' 32 " S, 96 ° 17 ' 31 " E), depth 932 – 965 m, 21 / 10 / 2022 (1 spec.); W. 55295 (LK 281), Christmas Island Territory, Balthazar Seamount (11 ° 21 ' 33 " S, 104 ° 2 ' 53 " E), depth 3510 – 3611 m, 7 / 10 / 2022 (1 spec.); W. 54396 (LK 279), Cocos (Keeling) Islands Territory, Rudist Seamount (11 ° 03 ' 47 " S, 99 ° 26 ' 36 " E), depth 3780 – 3839 m, 12 / 10 / 2022 (1 spec.); W. 55300 (LK 301), Cocos (Keeling) Islands Territory, Muirfield Seamount (13 ° 16 ' 41 " S, 96 ° 04 ' 06 " E), depth 1459 – 1595 m, 20 / 10 / 2022 (1 spec. prepared for SEM); W. 55293 (LK 272), Cocos (Keeling) Islands Territory, Rudist Seamount (11 ° 03 ' 47 " S, 99 ° 26 ' 36 " E), depth 3780 – 3839 m, 12 / 10 / 2022 (1 spec.); W. 54368 (LK 291), Cocos (Keeling) Islands Territory, Rudist Seamount (11 ° 03 ' 47 " S, 99 ° 26 ' 36 " E), depth 3780 – 3839 m, 12 / 10 / 2022 (1 spec.); W. 54420 (LK 308), Cocos (Keeling) Islands Territory, Rudist Seamount (11 ° 03 ' 47 " S, 99 ° 26 ' 36 " E), depth 3780 – 3839 m, 12 / 10 / 2022 (1 spec.); W. 54383 (LK 304), Cocos (Keeling) Islands Territory, Muirfield Seamount (13 ° 26 ' 12 " S, 96 ° 18 ' 17 " E), depth 3948 – 4047 m, 24 / 10 / 2022 (1 spec.); W. 54508 (LK 314), Christmas Island Territory, Attention Seamount (11 ° 45 ' 25 " S, 103 ° 16 ' 49 " E), depth 1401 – 1408 m, 9 / 10 / 2022 (1 spec. not removed from tube). Description. Tube: white or slightly brownish opaque, jirkovi Kupriyanova, 1993 c has elongate operculum and its with smooth surface, circular in cross-section, attached to collar’s ventral lobe has a deep medial incision, thus making substrate throughout its entire length (Fig. 10 A). the collar four-lobed. Hyalopomatus nogueirai n. sp. is most Radiolar crown: with up to 10 pairs of radioles (Fig. 10 B), similar to H. macintoshi (Gravier, 1911) from Antarctica and arranged pectinately, easily detachable from short radiolar H. mironovi from Kuril-Kamchatka Trench as both species lobes. Inter-radiolar membrane and stylodes absent. Terminal have globular transparent opercula, slightly flattened on top. filaments of radioles thin. Radiolar eyes and mouth palps However, both these species have tri-lobed collars, while not observed. in H. macintoshi tubes bear with well-developed flaring Peduncle: smooth, cylindrical, thin (approximately same peristomes. thickness as radioles) (Fig. 10 A); inserted outside radiolar The phylogenetic results also show that that H. cf. crown proper, between base of 1 st and 2 nd radioles. mironovi from North Fiji is nested inside the Hyalopomatus Collar and thoracic membranes: collar long, completely nogueirai n. sp. clade instead of forming a clade with H. covering radiolar lobes and distinctly unlobed (Fig. 10 B, I). mironovi from Kuril-Kamchatka Trench (the type locality). Collar continuous with short thoracic membranes ending at This suggests that the specimen attributed to H. mironovi by 2 nd chaetiger (Fig. 10 E). Kupriyanova et al. (2010) likely belongs to Hyalopomatus Operculum: soft membranous, semi-transparent, semi- nogueirai n. sp. globular, with flattened top, slightly differentiated from	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9B536B5CA84AD6FB4CF8D3.taxon	etymology	Etymology. The species is named after Professor João basal part; conspicuous constriction and additional small Miguel de Matos Nogueira (Universidade de São Paulo, vesicular ampulla between operculum and peduncle present Brazil) for his important contributions to serpulid (Fig. 10 A). Pseudoperculum absent. systematics. Thorax: with 6 chaetigerous segments, 5 of which uncinigerous (Fig. 10 I). Small bundle of collar chaetae (Fig. Distribution. Only known from seamounts off Christmas 10 E) of two types: limbate and fin-and-blade with distal and Cocos (Keeling) Islands, Indian Ocean, 932 – 4047 m. blade separated from basal fin by a short gap (Fig. 10 C). Subsequent chaetae limbate, of two sizes, Apomatus chaetae absent (Fig. 10 D). Uncini along entire thorax rasp-shaped, Hyalopomatus rossanae n. sp. with 20 – 25 small teeth in profile view, with 6 teeth in row above flat anterior peg made of 3 – 4 rounded lobes (Fig. urn: lsid: zoobank. org: act: 9675 EECD- 427 B- 4398 - 9 C 2 C- 1 A 123 B 8 B 9 C 6 E 10 H). Pair of prostomial eyes absent. Triangular depression Fig. 11 A – J absent, thoracic tori almost parallel to mid-lateral line of thorax (Fig. 10 B, I). Material examined. Holotype: W. 54369 (LK 289), Cocos Abdomen: with up to 55 segments. Chaetae long, nearly (Keeling) Islands Territory, Muirfield Seamount (13 ° 26 ' 12 " S, capillary with only narrow geniculate tip made of two rows 96 ° 18 ' 17 " E), depth 3948 – 4047 m, 24 / 10 / 2022. of pointed teeth (Fig. 10 G). Capillary chaetae present in Paratypes: W. 53432 (LK 260), Territory of Christmas posterior chaetigers (Fig. 10 F). Uncini rasp-shaped with over Island, Karma Seamount (12 ° 49 ' 33 " S, 107 ° 02 ' 48 " E), 20 teeth in profile and up to 8 rows of teeth (Fig. 10 J) above depth 2860 – 2850 m, 11 / 07 / 2021 (1 spec.); W. 53459 anterior peg flat divided into 3 – 5 rounded lobes (crenulated). (LK 267), Territory of Christmas Island, Clara Marie Achaetous anterior abdominal zone present. Seamount (13 ° 34 ' 35 " S, 105 ° 19 ' 39 " E), depth 2189 – 2264 m, Size: total body length up to 11 mm, including up to 12 / 07 / 2021 (1 spec.); W. 54374 (LK 294), Cocos (Keeling) 5.9 mm long radioles, 1.2 mm long thorax, 4.2 mm long Islands Territory, Investigator Ridge Abyssal (11 ° 15 ' 26 " S, abdomen, width of thorax 0.5 mm. External tube diameter 97 ° 58 ' 08 " E), depth 4980 – 4990 m, 12 / 10 / 2022 (1 spec.); up to 0.6 mm, corresponding lumen diameter 0.5 mm. W. 54378 (LK 292), Cocos (Keeling) Islands Territory (12 ° 13 ' 32 " S, 96 ° 57 ' 36 " E), depth 1113 – 1343 m, 17 / 10 / 2022 Diagnostic remarks. Hyalopomatus nogueirai n. sp. has an (1 spec. prepared for SEM); W. 54392 (LK 276), Cocos operculum with a differentiated endcap flattened at the top (Keeling) Islands Territory, Muirfield Seamount (13 ° 05 ' 33 " S, and a clearly unlobed collar. A distinct character of the new 96 ° 21 ' 09 " E), depth 2889 – 2923 m, 23 / 10 / 2022 (1 spec.); species is the multilobed pegs of thoracic uncini because W. 54394 (LK 277), Cocos (Keeling) Islands Territory, other species of the genus tend to have two-lobed pegs of Investigator Ridge Abyssal (11 ° 15 ' 26 " S, 97 ° 58 ' 08 " E), depth such uncini. The multilobed pegs of thoracic uncini are also 4980 – 4990 m, 12 / 10 / 2022 (1 spec.); W. 55292 (LK 307), found in H. dieteri, the species that is distinct in having Cocos (Keeling) Islands Territory, Rudist Seamount thick-walled, quadrangular in cross-section tubes. However, (11 ° 03 ' 47 " S, 99 ° 26 ' 36 " E), depth 3780 – 3839 m, 12 / 10 / 2022 at least some two-lobed uncini in older literature may be due (1 spec.). to high power microscope observations, misinterpreting the real structure of the “ gouged ” peg. Description. Tube: white opaque, with shiny surface, The multilobed thoracic uncini formally separate the thin-walled, circular in cross-section, attached to substrate new species from other congeners having globular or pear- throughout entire length, no keels, peristomes or obvious shaped vesicular opercula without differentiated distal caps transverse ridges or growth lines (Fig. 11 C, D). (H. claparedii Marenzeller, 1878, H. langerhansi Ehlers, Radiolar crown: with 6 – 7 pairs of radioles, arranged 1887, and H. sombrerianus (McIntosh, 1885 )). It is distinct pectinately, easily detachable from short radiolar lobes. Interfrom H. nigropileatus (Ehlers, 1900) having an elongate radiolar membrane and stylodes absent. Terminal filaments spindle-shaped operculum covered with dark violet or black of radioles thin, spirally twisted. Radiolar eyes and mouth distal cap with a net-like structure, and H. sikorskii having palps not observed. an operculum with distal dark cap flat on top resembling a Peduncle: smooth, cylindrical, approximately same brimless domed hat without net-like structure. Hyalopomatus thickness as normal radioles (Fig. 11 B), inserted outside radiolar crown, between base of 1 st and 2 nd radioles. Material examined. Holotype: W. 54438 (LK 278); Cocos Collar and thoracic membranes: collar long covering (Keeling) Islands Territory, Cocos (Keeling) (12 ° 1 ' 10 " S, radiolar lobes, trilobed, with ventral lobe at least twice as 96 ° 50 ' 11 " E), depth 754 – 890 m, 16 / 10 / 2022. Paratype: long as lateral ones (Fig. 11 B). Collar continuous with short W. 54366 (LK 285), same as above (1 spec. prepared for rounded thoracic membranes ending at 2 nd chaetiger (Fig. SEM). 11 A, B).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9B536B5CA84AD6FB4CF8D3.taxon	description	Description. Tube: white opaque, with shiny surface, Operculum: soft membranous, semi-transparent, straight, thin-walled, brittle, circular in cross-section, keels elongated with convex brown cap, distinctly differentiated and peristomes absent, distinct breaks present (Fig. 12 A). from basal part; conspicuous constriction and additional Radiolar crown: with 7 pairs of radioles in holotype, small vesicular ampulla between operculum and peduncle arranged pectinately, easily detachable from short radiolar (Fig. 11 B, C, E, e). Pseudoperculum absent. lobes. Inter-radiolar membrane and stylodes absent. Terminal Thorax: with 6 chaetigerous segments, 5 of which filaments of radioles thin, spirally twisted. Radiolar eyes and uncinigerous (Fig. 11 A, B). Small bundle of collar chaetae mouth palps not observed. of two types: simple limbate and fin-and-blade with distal Peduncle: smooth, cylindrical, thin (approximately same blade separated from basal fin by a short gap (Fig. 11 F, J). thickness as radioles) (Fig. 12 A, a). Subsequent chaetae limbate, of two sizes, Apomatus chaetae Collar and thoracic membranes: collar long, covering absent (Fig. 11 I). Uncini along entire thorax rasp-shaped, radiolar lobes, trilobed, with ventral lobe distinctly higher with 20 – 25 small teeth in profile view, with 6 – 8 teeth in than lateral ones. Collar continuous with short thoracic row above flat peg made of two rounded lobes (Fig. 11 G). membranes ending at 3 rd chaetiger. Pair of prostomial eyes absent. Triangular depression absent, Operculum: soft membranous, semi-transparent, distinctly thoracic tori almost parallel to mid-lateral line of thorax. globular, no distal cap; conspicuous constriction and Abdomen: with up to 40 segments. Abdominal chaetae additional small vesicular ampulla between operculum and not observed, likely absent. Uncini rasp-shaped with over 20 peduncle absent (Fig. 12 A). Pseudoperculum absent. teeth in profile and up to 9 rows of teeth (Fig. 11 H) above Thorax: with 6 chaetigerous segments, 5 of which anterior peg flat divided into 3 – 4 rounded lobes (crenulated). uncinigerous. Small bundle of collar chaetae, of two types: Achaetous anterior abdominal zone long. limbate and fin-and-blade with distal blade separated from Size: total body length up to 7.0 mm, including up to indistinct basal fin by a short gap (Fig. 12 B). Subsequent 3.0 mm long radioles, up to 1.0 mm long thorax, 3.0 mm chaetae limbate, of two sizes, Apomatus chaetae absent (Fig. long abdomen, width of thorax up to 0.2 mm. External tube 12 D). Uncini along entire thorax rasp-shaped, with 20 – 25 diameter in holotype 0.3 mm, corresponding lumen diameter small teeth in profile view and 6 – 8 teeth in row above flat 0.25 mm. anterior peg made of two rounded lobes (Fig. 12 C). Pair Diagnostic remarks. The tiny new species is most similar to of prostomial eyes absent. Triangular depression absent, Hyalopomatus nigropileatus, H. jirkovi Kupriyanova, 1993 c, thoracic tori almost parallel to mid-lateral line of thorax. and H. sikorskii Kupriyanova, 1993 c by having an elongate Abdomen: with up to 35 segments. Chaetae long, nearly operculum covered with a darker distal cap. Hyalopomatus capillary with only narrow geniculate tip made of two rows rossanae n. sp. differs from H. nigropileatus that is distinct of pointed teeth (Fig. 12 F). Capillary chaetae present in in having dark violet or black cap with a net-like structure. posterior chaetigers. Uncini rasp-shaped with over 20 teeth in The new species differs from H. sikorskii (having operculum profile and up to 9 rows of teeth (Fig. 12 E) above anterior peg with a distal dark cap flat on top) by having a trilobed collar flat divided into 3 – 5 rounded lobes (crenulated). Achaetous with very long ventral lobe, whereas H. sikorskii has short anterior abdominal zone absent. collar with lobes of equal length. Finally, although both Size: total body length up to 7.0 mm, including up to 1.4 Hyalopomatus rossanae n. sp. and H. jirkovi have the collar mm long radioles, 1.2 mm long thorax, 4.4 mm abdomen, with the ventral lobe much longer than the lateral ones, the width of thorax up to 0.3 mm. External tube diameter in ventral lobe of collar in H. jirkovi has a deep medial incision, holotype 0.4 mm, corresponding lumen diameter 0.35 mm. thus making the collar four-lobed. Diagnostic remarks. The new species is characterised by The molecular results here supported monophyly of its distinctly globular operculum lacking any differentiated the genus Hyalopomatus and placement of Hyalopomatus distal cap and its straight tube with smooth shiny surface, rossanae n. sp. in this genus. attached only by the posterior part to substrate. Other similar	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9B536B5CA84AD6FB4CF8D3.taxon	etymology	Etymology. The species is named in honour Professor Hyalopomatus spp. having opercula without differentiated Rossana Sanfilippo (University of Catania, Italy), an expert distal caps are H. claparedii Marenzeller, 1878 from the on systematics and palaeoecology of Serpulidae and other Arctic Ocean and H. mironovi Kupriyanova, 1993 c from tube-dwelling polychaetes. the Kuril-Kamchatka Trench in the North-West Pacific Ocean. Hyalopomatus suelindsayae n. sp. having a globular	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9B536B5CA84AD6FB4CF8D3.taxon	distribution	Distribution. Only known from seamounts off Christmas operculum differs from H. claparedii and H. mironovi that and Cocos (Keeling) Islands, Indian Ocean, 1113 – 4990 m. have pear-shaped opercula. Hyalopomatus mironovi also has tubes with slight transverse ridges and special collar chaetae Hyalopomatus suelindsayae n. sp. with The a distinct new species large fin also well appears separated to from be morphologically the distal blade. urn: lsid: zoobank. org: act: 414 F 6723 - 28 BD- 4 EA 0 - 9989 - C 6 C 4 F 93128 F 5 different from the poorly known taxa H. sombrerianus and H. langerhansi, both from West Atlantic Ocean. Hyalopomatus Fig. 12 A – F sombrerianus, originally described as Serpula sombreriana McIntosh, 1885, was based on a single dry non-operculate specimen 12 mm long, dredged off Sombrero, St. Thomas, the Caribbean Sea, in 859 – 713 m. The taxon was transferred to Hyalopomatus by ten Hove in Ben-Eliahu and Fiege (1996). The type examined by ten Hove proved to be a mutilated specimen with broken chaetae (fide Ben-Eliahu & Fiege, 1996). The status of this species is uncertain, both Ben-Eliahu and Fiege (1996) and ten Hove and Kupriyanova (2009) suggested that the species is probably includes H. langerhansi. The description of the latter species was based on two finds collected by the “ Blake ” expedition (1868), northwest of Cuba (near Havana in 535 m, and 23 ° 42 ' N 83 ° 19 ' W, in 1572 m) (fide Zibrowius, 1969). According to Hartman (1938), the type material is badly damaged. The specimens have tubes with a sub-quadrangular section in its attached part, having two slight keels, which is a potential diagnostic character. As in H. claparedii, the operculum of H. langerhansi is a transparent pear-shaped vesicle. Molecular results of this study indicate that H. suelindsayae n. sp. from IOT is most closely related to an unnamed Hyalopomatus sp. 1 from the Jaco Summit hydrothermal seep on the Costa Rica margin and to H. mironovi collected from the Kuril-Kamchatka trench. The taxonomic status of Hyalopomatus spp. populations from these localities needs to be examined into further studies.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9B536B5CA84AD6FB4CF8D3.taxon	etymology	Etymology. The species was named to honour Sue Lindsay, formerly Australian Museum, now SEM laboratory manager at Macquarie University, Sydney for her invaluable help and support over years.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9B536B5CA84AD6FB4CF8D3.taxon	distribution	Distribution. Only known from Cocos (Keeling) Islands Territory, Indian Ocean, 754 – 890 m.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9153645FDF49A5FE76FA23.taxon	type_taxon	Type species. Placostegus tridentatus (Fabricius, 1779) Generic diagnosis (from ten Hove & Kupriyanova, 2009). Tube triangular in cross-section, with denticulate keels, transparent or semi-transparent, often only attached to substratum at base, collar-like rings absent. Granular overlay absent. Operculum inverse conical, with chitinous cup-shaped endplate. Peduncle cylindrical, smooth, without wings, gradually merging into operculum, at most with shallow constriction; inserted at base of radioles on one side between 1 st and 2 nd normal radiole and maximally covering base of first three radioles. Pseudoperculum absent. Radioles arranged in semi-circles, up to 24 per lobe; inter-radiolar membrane, radiolar eyes, and stylodes absent. Mouth palps present. Six thoracic chaetigerous segments. Collar tri- to penta-lobed, collar edge may be almost laciniate; tonguelets between ventral and lateral collar lobes present. Thoracic membranes long, forming ventral apron across anterior abdominal segments. Collar chaetae absent; collar region with girdle of reddish ocelli. Apomatus chaetae absent. All uncini sub-rectangular, rasp-shaped with> 20 teeth in profile, and up to 8 small teeth in a row; anterior peg wide, flat, bluntly truncate, almost rectangular. Thoracic triangular depression absent. Abdominal chaetae true trumpet-shaped, with distal hollow triangular blade, abruptly bent. Achaetous anterior abdominal zone present. Long posterior capillary chaetae may be present. Posterior glandular pad absent.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9153645FDF49A5FE76FA23.taxon	discussion	Remarks. Placostegus and Vitreotubus (see below) are the only two serpulins with an entirely vitreous tube. Placostegus has one evident diagnostic autapomorphy – the belt of bright red ocelli in the region where in other genera collar chaetae are found (ten Hove & Kupriyanova, 2009, fig. 1 F). Unexpectedly, despite clear morphological similarities and identifiable synapomorphies, the genus was not recovered as a monophyletic clade in this study. However, because this phylogenetic position based on 18 S sequence data alone contradicts monophyly of the genus Placostegus demonstrated in the multigene analysis of Serpulidae in Kupriyanova et al., 2023, here we did not change the nomenclature until further molecular data on Placostegus spp. become available.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9153655FC14CF6FB17F967.taxon	description	Fig. 13 A – E	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9153655FC14CF6FB17F967.taxon	materials_examined	Material examined. Holotype: W. 54407 (LK 311), Cocos (Keeling) Islands Territory, Muirfield Seamount (13 ° 10 ' 06 " S, 96 ° 11 ' 14 " E), depth 271 – 311 m, 22 / 10 / 2022 (photo, DNA and SEM). Paratype: W. 54410, Cocos (Keeling) Islands Territory, Muirfield Seamount (13 ° 11 ' 13 " S, 96 ° 08 ' 51 " E), depth 367 m, 23 / 10 / 2022 (1 empty tube).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9153655FC14CF6FB17F967.taxon	description	Description. Tubes: triangular in cross section, thick-walled, nearly transparent (Fig. 13, A, a; smaller empty white tubes unidentifiable). Tube attached to substrate for most of its length, only distal-most part free, tube mouth rounded, lacking any denticles. Radiolar crown: 22 radioles not connected by inter-radiolar membrane at base. Peduncle: smooth cylindrical, only slightly wider than normal radioles (Fig. 13 A, a, B), inserted medio-dorsally at base of radiolar lobe. Collar and thoracic membranes: collar trilobed, long, covering radiolar lobes and proximal part of radioles. Lobes approximately of same length, dorsal lobe wider than lateral lobes. Collar margin smooth. Collar chaetae absent. Operculum: elongated inverted cone covered with a slightly concave brown chitinous endplate (Fig. 13 A, a, B). Constriction between operculum and peduncle present (Fig. 13 A, a, B). Thorax: short, compact, thoracic notopodia positioned close to each other, along mid-lateral line of thorax, triangular depression absent. Collar segment with girdle of redpigmented ocelli (Fig. 13 b). Thoracic membranes continuing to end of thorax forming short apron ventrally. Thoracic chaetae (Fig. 13 C) simple limbate of two sizes, Apomatus chaetae absent. Thoracic uncini (Fig. 13 D) rasp-shaped, with over 200 small teeth in profile view and up to 10 teeth per row, anterior peg wide with rounded edges. Abdomen: chaetae with long shafts (Fig. 13 E) and distal tips with 2 – 3 rows of small denticles (Fig. 13 e). Chaetae of posterior abdominal segments slightly longer than more anterior ones. Abdominal uncini similar to thoracic uncini. Achaetous anterior abdominal zone present. Long posterior capillary chaetae present. Posterior glandular pad absent. Size: total body length of holotype 16.9 mm, including up to 5.2 mm long radioles, up to 1.6 mm long thorax, 10.1 mm long abdomen, width of thorax 0.7 mm. External tube diameter in holotype 1.3 mm, corresponding lumen diameter 1.1 mm. Diagnostic remarks. According to WoRMS (Read & Fauchald, 2024), six species are currently considered valid in the genus Placostegus. The best known species Placostegus tridentatus originally described from Northern Europe is recognisable by its transparent triangular tube with keels extended into three denticles at the mouth and radially symmetrical operculum. The species has been widely reported not only from the Mediterranean and the Atlantic Ocean, but also from the Indo-West Pacific, an unlikely distribution for a shallow-water species. However, the only record from Japan was reported by Imajima (1978), who stressed that he referred his material to P. tridentatus only tentatively and that a revision of the genus is needed. Placostegus assimilis McIntosh, 1885 fromtheBermudas has a radially symmetrical operculum and tube with a denticulate mouth, according to the original illustration, but the tube mouth of P. assimilis has more than three main denticles unlike that of P. tridentatus. Both Placostegus langerhansi Marenzeller, 1893 from Madeira and Placostegus californicus Hartman, 1969 from California have distinctly zygomorphic (bilaterally symmetrical) opercula and tubes with tri-denticulate mouths, but apparently these species differ by the collar having seven lobes in the former and three lobes in the latter. Placostegus crystallinus (non-Scacchi, 1837) sensu Zibrowius, 1968 (likely an undescribed species) has a recognisable tube with numerous rounded transverse ridges and somewhat similar ridges in the posterior part of the tube have been reported for Placostegus incomptus Ehlers, 1887. The new species is distinct from all described species of the genus because of the combination of radially symmetrical operculum and the tube with a rounded mouth lacking any denticles. In this respect the new species resembles Placostegus sp. from Lizard Island, Qld, Australia (Kupriyanova et al., 2015, fig. 14 B, C). Also, abdominal chaetae in P. leslieharrisae n. sp. are similar to the abdominal chaetae found in some Hyalopomatus spp. (see above) in having distal tips with 2 – 3 rows of small denticles. The tips (Fig. 13 E) are not hollow and are very different from the almost rectangular angle of the true trumpet-shaped chaetae as illustrated in ten Hove and Kupriyanova (2009, fig. 34 C) for P. tridentatus. This is the first newly described species of the genus in which a detailed illustrated description is accompanied by the molecular sequence data from the type specimen.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9153655FC14CF6FB17F967.taxon	etymology	Etymology. The species was named in honour of Leslie Harris (Senior Collection Manager, Natural History Museum of Los Angeles County, CA, USA) for her remarkable dedication to studies of polychaetes and her important contributions to the field of polychaete taxonomy.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9153655FC14CF6FB17F967.taxon	distribution	Distribution. Only known from Muirfield Seamount, Cocos (Keeling) Islands, Indian Ocean, 271 – 367 m.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9053665C7B4FCCFC3AFE61.taxon	type_taxon	Type species. Vitreotubus digeronimoi Zibrowius, 1979 Generic diagnosis (from ten Hove & Kupriyanova, 2009). Tube entirely vitreous, more or less quadrangular in cross-section by its two large undulating lateral keels, and with a median keel made of a row of teeth. Operculum inverse conical with chitinous diabolo-like endplate. Peduncle smooth, cylindrical, merging gradually into operculum, without wings, inserted as first radiole. Pseudoperculum absent. Arrangement of radioles short pectinate, up to 11 per lobe. Inter-radiolar membrane and stylodes absent. Radiolar eyes not observed. Mouth palps present. Seven thoracic chaetigerous segments. Collar trilobed. Medial lobe of collar with scalloped edge and lateral projections, separated from lateral lobes by deep incision (tonguelets absent), latter continuous with thoracic membranes extending all along thorax, but narrow in posterior segments, forming ventral apron. Collar chaetae Spirobranchus - type and simple limbate. Apomatus chaetae absent. Thoracic uncini saw-shaped with 6 – 7 teeth above pointed fang. Triangular depression present. Abdominal chaetae true trumpet-shaped, with two rows of pointed teeth bordering hollow groove and extended into a long lateral spine. Abdominal uncini saw-shaped with about 6 teeth anteriorly, rasp-shaped with about 10 teeth in profile, 3 – 4 teeth in a row posteriorly. Achaetous anterior abdominal zone absent. Posterior capillary chaetae absent, but geniculate chaetae long at end of abdomen. Posterior glandular pad absent.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9053665C7B4FCCFC3AFE61.taxon	discussion	Remarks. The monotypic genus was originally described from fossil records and Recent material collected in the bathyal zone off the Azores and in the Indian Ocean (Zibrowius, 1979), more recent records are given by ten Hove (1994).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9353675CB748DFFC55F831.taxon	description	Figs. 14 A – C, 15 A – E	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9353675CB748DFFC55F831.taxon	description	empty tubes only); Vinn, 2005: 262 – 262, fig. 5 (tube ultrastructure); ten Hove & Kupriyanova, 2009: 103 – 104, fig. 50 (SEM of chaetae).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9353675CB748DFFC55F831.taxon	materials_examined	Material examined: W. 54402, Cocos (Keeling) Islands Territory, Muirfield Seamount (13 ° 10 ' 28 " S, 96 ° 14 ' 14 " E), depth 528 m, 21 / 10 / 2022 (1 tube); W. 54409 (LK 295), Cocos (Keeling) Islands Territory, Muirfield Seamount (13 ° 10 ' 28 " S, 96 ° 14 ' 14 " E), depth 528 m, 21 / 10 / 2022 (1 spec); W. 55301 (LK 317), same locality (1 spec. prepared for SEM). Species diagnosis. Tube entirely vitreous (Fig. 14 A, C), more or less quadrangular in cross-section, by its two large undulating (Fig. 14 C) or distinctly denticulate lateral keels (Fig. 14 C), and with a median keel made of a row of short teeth. Operculum inverse conical with chitinous diabolo-like endplate (Fig. 14 B, 15 A). Seven thoracic chaetigerous segments. Collar trilobed. (Fig. 14 B, 15 A). Apomatus chaetae absent (Fig. 15 B). Thoracic uncini saw-shaped with 6 – 7 teeth above pointed fang (Fig. 15 C). Abdominal chaetae true trumpet-shaped, with two rows of pointed teeth bordering hollow groove and extended into a long lateral spine (Fig. 15 D). Abdominal uncini saw-shaped with about 6 teeth anteriorly (Fig. 15 E).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9353675CB748DFFC55F831.taxon	discussion	Remarks. The species has a very characteristically shaped transparent tube. Not surprisingly, the irregular spherulitic prismatic tube ultrastructure of Vitreotubus closely resembles that of Placostegus tridentatus, a species with similarly transparent tube (Vinn, 2005). Zibrowius (1979) designated the station 229 / 9.11.1971 of RV “ Jean Charcot ” Campagne Biaçores collected NW of Santa Maria, Azores (37 ° 01.5 ' N, 25 ° 14 ' W, 600 m) as the type locality of V. digeronimoi, but his additional material came from Northern (off Kuria Muria Islands off Oman coast) and Southern (Mayotte) Indian Ocean localities. The depth range reported for the species is 500 – 1415 m. Here we provide a new record from Southern Indian Ocean (Muirfield Seamount) of this poorly known, but apparently widely distributed bathyal species and, more importantly, we provide the first DNA sequence data for this species.	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
03CF5E32FF9353675CB748DFFC55F831.taxon	distribution	Distribution. Central Atlantic and Indian Ocean; bathyal (500 – 1415 m).	en	Kupriyanova, Elena K., Flaxman, Beth (2024): Serpulidae (Annelida) of the Australian Indian Ocean Territories. Records of the Australian Museum (Rec. Aust. Mus.) 76 (4): 211-242, DOI: 10.3853/j.2201-4349.76.2024.1901, URL: https://doi.org/10.3853/j.2201-4349.76.2024.1901
