Peronia sydneyensis Dayrat & Goulding, 2020

Dayrat, Benoit, Goulding, Tricia C., Apte, Deepak, Aslam, Sadar, Bourke, Adam, Comendador, Joseph, Khalil, Munawar, Ngo, Xuan Qu ảng, Tan, Siong Kiat & Tan, Shau Hwai, 2020, Systematic revision of the genus Peronia Fleming, 1822 (Gastropoda, Euthyneura, Pulmonata, Onchidiidae), ZooKeys 972, pp. 1-224 : 1

Peronia sydneyensis Dayrat & Goulding sp. nov. Figs 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58

Type material.

Holotype. Australia • holotype, hereby designated, 30/20 mm [1516 H]; New South Wales, Sydney, Pittwater, Church Point; 33°39.107'S, 151°17.363'E; 24 Nov 2011; B Dayrat, R Golding & WF Ponder leg.; st 39, sand, next to a small patch of mangrove, and rocks on sandy beach; AM C.468916.001.

Additional material examined.

Australia - New South Wales • 1 specimen 23/15 mm [1517]; same collection data as for the holotype; AM C.468915.001. • 1 specimen 16/12 mm [1513]; same collection data as for the holotype; AM C.468912.004. - Queensland • 1 specimen 20/17 mm [1539]; Shoalwater Bay, off Canoe Passage between Townshend & Marquis Islands; 22°18.235'S, 150°27.543'E; 9 & 10 Sep 2002; I Loch, DL Beechey & AC Miller leg.; st M2002/52, rocky shoal with coarse muddy sand; AM C.459510. • 2 specimens 30/20 [1540] mm and 20/20 mm [734]; Port Clinton, beach SW of Mt Flinders; 22°32.76'S, 150°45.54'E; 1 Sep 2002; I Loch, DL Beechey & AC Miller leg.; under and on rocks, sheltered muddy sand shore; AM C.459511. • 1 specimen 50/30 mm [2680]; Mackay, Campwin Beach; 21°22.455'S, 149°18.753'E; 5 Jul 2013; TC Goulding and field party leg.; st 121, by boat ramp, mangrove margin with large rocks by creek, Rhizophora and soft mud; MTQ. • 1 specimen 10/6 mm [2653]; Bowen, Doughty Creek; 20°01.376'S, 148°14.351'E; 2 Jul 2013; TC Goulding and field party leg.; st 118, across Doughty’s creek, coarse sandy area; MTQ. • 1 specimen 12/9 mm [2656]; same collection data as for the preceding; MTQ. • 1 specimen 50/30 mm [2661]; Bowen; 20°01.478'S, 148°14.224'E; 3 Jul 2013; TC Goulding and field party leg.; st 119, rocks on beach near a Rhizophora and Avicennia mangrove; MTQ. • 1 specimen 15/10 mm [2662]; same collection data as for the preceding; MTQ. • 1 specimen 15/10 mm [2664]; same collection data as for the preceding; MTQ. • 1 specimen 6/4 mm [2667]; same collection data as for the preceding; MTQ. • 1 specimen 9/6 mm [2646]; Bowen, Doughty Creek; 20°01.264'S, 148°14.345'E; 2 Jul 2013; TC Goulding and field party leg.; st 117, narrow Avicennia and Rhizophora mangrove, by creek, some muddy areas and some very sandy; MTQ.

New Caledonia • 1 specimen 12/7 mm [6189]; Baie de Taaré; 22°15.286'S, 167°00.808'E; 19 Sep 2018; Our Planet Reviewed Koumac 2018 expedition leg.; st KM524, intertidal sandy coral rubble flat in front of mangroves; MNHN-IM-2019-1594. • 1 specimen 41/25 mm [6195]; same collection data as for the preceding; MNHN-IM-2019-1595. • 1 specimen 33/19 mm [6209]; Nouméa, Pointe des Dorades; 22°11.507'S, 166°25.951'E; 22 Sep 2018; Our Planet Reviewed Koumac 2018 expedition leg.; st KM530, firm mud amongst muddy rocks and gravel in front of a seaward fringing Rhizophora forest; MNHN-IM-2019-1596. • 1 specimen 21/12 mm [6213]; Pointe Sauveur, Presqu’île de Ouano; 21°52.006'S, 165°49.195'E; 26 Sep 2018; Our Planet Reviewed Koumac 2018 expedition leg.; st KM538, muddy intertidal rocky flat in front of mangroves; MNHN-IM-2019-1597. • 1 specimen 25/11 mm [6220]; Pointe Vidoire, Bourail; 21°37.572'S, 165°27.595'E; 27 Sep 2018; Our Planet Reviewed Koumac 2018 expedition leg.; st KM539, landlocked coastal mangrove, small pocket of Rhizophora stylosa and Avicennia marina with a large brackish pool set behind a stony beach; MNHN-IM-2019-1598. • 1 specimen 26/16 mm [6222]; same collection data as for the preceding; MNHN-IM-2019-1599.

Distribution

(Fig. 6 ). Southern West Pacific: New South Wales (type locality) and Queensland (up to 20°S), Australia, and New Caledonia.

Etymology.

Peronia sydneyensis is named after its type locality in Sydney, New South Wales, Australia: sydneyensis is a latinized adjective that agrees in gender (feminine) with the generic name ( ICZN 1999: Article 31.2).

Habitat

(Fig. 49 ). Unlike most other Peronia species, which are found in the rocky intertidal, P. sydneyensis is primarily found on muddy or coarse sand.

Color and morphology of live animals

(Figs 50 , 51 ). The dorsal notum is greenish brown, light to dark, mottled with darker and lighter areas. The color of the dorsal papillae varies as that of the background itself. The ventral surface (foot and hyponotum) varies from whitish to dark grey, including yellowish, bluish, and greenish, and can change rapidly in any given individual. The ocular tentacles are brown-grey, like the head. The dorsal notum of live animals is covered by dozens of papillae of various sizes. Some papillae bear black dorsal eyes at their tip. The number of papillae with dorsal eyes is variable (from 8 to 16). The largest specimens are 30 mm long (New South Wales), 50 mm long (Queensland), and 41 mm long (New Caledonia).

Digestive system

(Figs 52 - 54 ). Examples of radular formulae are presented in Table 5 . The median cusp of the rachidian teeth is approximately 40 μm long. The hook of the lateral teeth is approximately 80 μm long. The intestinal loops are of type I, with a transitional loop oriented between 3 and 6 o’clock; exceptionally, the transitional loop is oriented at 2 o’clock.

Reproductive system

(Figs 55 - 58 ). In the anterior (male) parts, the muscular sac of the accessory penial gland is less than 10 mm long. The hollow spine of the accessory penial gland is narrow, elongated, and straight or slightly curved, and its shape (including at its tip) varies between individuals. Its length ranges from 0.6 mm ([2680] MTQ) to 1 mm ([2661] MTQ). Its diameter at the conical base ranges from 90 to 100 μm. Its diameter at the tip measures 20-50 μm. The retractor muscle is shorter or longer than the penial sheath and inserts near the heart. Inside the penial sheath, the penis is a narrow, elongated, soft, hollow tube. Its distal end bears conical hooks which are less than 30 μm long.

Diagnostic features

(Table 4 ). Peronia sydneyensis is characterized by unique and distinctive protuberances on the spine of the accessory penial gland (Fig. 58 ). These strong protuberances were observed in all individuals. Protuberances can also be observed (as exceptional cases) in other species but they are always much smaller in size (Figs 37D , 104B , 105F ). In addition, Peronia sydneyensis is characterized by a unique combination of anatomical traits: intestinal loops of type I (with a transitional loop oriented between 3 and 6 o’clock), retractor muscle inserting at the posterior end of the visceral cavity, spine of the accessory penial gland less than 1 mm long. Peronia sydneyensis is distinct anatomically from P. willani , with which it is most closely related (Figs 2 - 4 ), and from P. verruculata , with which it overlaps geographically in Queensland and New Caledonia (Fig. 6 ).

Remarks.

A new species name is needed because no existing name applies to the species described here. The records of Onchidium verruculatum from New South Wales ( Bretnall 1919: 310; Dakin 1947: 144; Smith and Kershaw 1979: 92; Hutchings and Recher 1982: 119; Hyman 1999) are most likely records of Peronia sydneyensis , the only Peronia species known in New South Wales based on current data (Fig. 6 ). Some of these records (or even all of them) could be a combination of both P. sydneyensis and P. verruculata : the southernmost locality of P. verruculata (unit #1) is in MacKay, Queensland (21°22'S), but given that P. verruculata tolerates colder waters in Japan (up to at least 33°40'N), it is possible that it is also present in New South Wales. Peronia sydneyensis was collected only in Sydney (33°39'S), but it is not excluded that both species are sympatric as far south as Sydney. Additional fresh material between southern Queensland and New South Wales is needed to determine more precisely the geographic range of each species. Note that the intestinal loops of type II by Hyman (1999: fig. 7B) illustrate the digestive system of a misidentified individual (most likely Paromoionchis daemelii , easily confused in the field with Peronia sydneyensis ). Finally, note that the specimen [734] (AM C.459511) was tentatively referred to as Peronia sp. 3 by Dayrat et al. (2011).

Figures

Figure 2. Phylogenetic relationships between Peronia species based on concatenated mitochondrial COI and 16 S DNA sequences. Numbers by the branches are the bootstrap values (maximum likelihood analysis) and the posterior probabilities (Bayesian analysis). Only the values> 50 % (ML) and> 0.9 (Bayesian) are indicated. Numbers for each individual correspond to unique identifiers for DNA extraction. Information on specimens can be found in the lists of material examined and in Table 2. The color used for each species or mitochondrial unit is the same as the color used in Figs 3 - 6.

Figure 4. Maximum parsimony consensus tree within Peronia based on concatenated nuclear ITS 2 and 28 S sequences. Numbers by the branches are the bootstrap values. Only the values> 50 % are indicated. Numbers for each individual correspond to unique identifiers for DNA extraction. Information on specimens can be found in the lists of material examined and in Table 2. The color used for each species or mitochondrial unit is the same as the color used in Figs 2, 3, 5, 6.

Figure 6. Geographical distribution of the Peronia species A distribution of all Peronia species except for P. peronii B distribution of P. peronii. The colors are the same as those used in Figs 2 - 5. Colored areas correspond to hypothetical geographical ranges based on confirmed records only. Distinct colors are used for each unit of P. verruculata. The distribution of P. verruculata in the Indo-West Pacific is actually continuous. However, because it is unclear which units are present in regions from where we have no fresh material of P. verruculata (red areas), no unit of P. verruculata is shown there. For P. peronii, black dots correspond to material identified based on anatomical characters and blue dots correspond to material with DNA sequences. Details on species distribution can be found in each species description.

Figure 37. Penis and penial hooks, Peronia setoensis, Japan, Honshu A, B holotype [5383 H] (NSMT-Mo 78985) C, D [3753] (NSMT-Mo 78987) E, F [3754] (NSMT-Mo 78987). Scale bars: 40 μm (A), 4 μm (B), 100 μm (C), 2 μm (D, F), 20 μm (E).

Figure 49. Habitats, Peronia sydneyensis A Australia, New South Wales, sand, next to a small patch of mangrove, and rocks on sandy beach (st 39, type locality) B Australia, Queensland, Rhizophora, across Doughty's creek, coarse sandy area (st 118) C Australia, Queensland, Sonneratia, rocks on beach near a Rhizophora and Avicennia mangrove (st 119) D Australia, Queensland, by boat ramp, mangrove margin with large rocks by creek (st 121) E New Caledonia, intertidal sandy coral rubble flat in front of a mangrove (st KM 524) F New Caledonia, landlocked coastal mangrove, small pocket of Rhizophora and Avicennia with a large brackish pool set behind a stony beach (st KM 539) G New Caledonia, muddy intertidal rocky flat in front of mangroves (st KM 538).

Figure 50. Live animals, Peronia sydneyensis A holotype, dorsal view, 30 mm long [1516 H], Australia, New South Wales (AM C. 468916.001) B dorsal view, 15 mm long [2664], Australia, Queensland (MTQ) C dorsal view, 9 mm long [2646], Australia, Queensland (MTQ) D dorsal view, 50 mm long [2661], Australia, Queensland (MTQ) E ventral view, 15 mm long [2662], Australia, Queensland (MTQ) F Ventral view, 6 mm long [2667], Australia, Queensland (MTQ) G Ventral view, same as B.

Figure 51. Live animals, Peronia sydneyensis, New Caledonia A dorsal view, 12 mm long [6189] (MNHN-IM- 2019 - 1594) B dorsal view, 41 mm long [6195] (MNHN-IM- 2019 - 1595) C dorsal view, 26 mm long [6222] (MNHN-IM- 2019 - 1599) D dorsal view, 33 mm long [6209] (MNHN-IM- 2019 - 1596) E ventral view, same as A; F ventral view, same as B; G ventral view, same as D.

Figure 52. Digestive system, dorsal view, Peronia sydneyensis. The arrow indicates the orientation of the transitional loop A holotype, Australia, New South Wales, [1516 H] (AM C. 468916.001) B Australia, New South Wales, [1517] (AM C. 468915.001) C Australia, Queensland, [2680] (MTQ) D New Caledonia, [6195] (MNHN-IM- 2019 - 1595) E New Caledonia, [6209] (MNHN-IM- 2019 - 1596). Scale bars: 4 mm (A, C), 3 mm (B, D, E). Abbreviations: ddg dorsal digestive gland, i intestine, pdg posterior digestive gland, st stomach.

Figure 53. Radula, Peronia sydneyensis, Australia, New South Wales A-D holotype [1516 H] (AM C. 468916.001) E, F [1517] (AM C. 468915.001) A rachidian and innermost lateral teeth B lateral teeth C lateral teeth D lateral and outermost lateral teeth E rachidian and innermost lateral teeth F rachidian and lateral teeth. Scale bars: 20 μm (A, C, E), 50 μm (D), 100 μm (B, F).

Figure 54. Radula, Peronia sydneyensis A, B Australia, Queensland C-F New Caledonia A lateral teeth, [2680] (MTQ) B rachidian and innermost lateral teeth, [2680] (MTQ) C rachidian and innermost lateral teeth, [6189] (MNHN-IM- 2019 - 1594) D lateral and outermost lateral teeth, [6189] (MNHN-IM- 2019 - 1594) E lateral teeth, [6195] (MNHN-IM- 2019 - 1595) F lateral teeth, [6220] (MNHN-IM- 2019 - 1598). Scale bars: 100 μm (A), 20 μm (B-D), 40 μm (E), 10 μm (F).

Figure 55. Posterior, hermaphroditic (female) reproductive system, Peronia sydneyensis A holotype, Australia, New South Wales, [1516 H] (AM C. 468916.001) B New Caledonia, [6195] (MNHN-IM- 2019 - 1595). Scale bars: 2 mm (A, B). Abbreviations: dd deferent duct, fgm female gland mass, hg hermaphroditic gland, ov oviduct, rs receptaculum seminis, sp spermatheca

Figure 56. Anterior, male, copulatory apparatus, Peronia sydneyensis A holotype, Australia, New South Wales, [1516 H] (AM C. 468916.001) B New Caledonia, [6195] (MNHN-IM- 2019 - 1595). Scale bars: 3 mm (A, B). Abbreviations: ag accessory penial gland, dd deferent duct, ms muscular sac, ps penial sheath, rm retractor muscle, v vestibule.

Figure 57. Penis and penial hooks, Peronia sydneyensi A holotype, [1516 H], Australia, New South Wales (AM C. 468916.001) B same as A; C [2680], Australia, Queensland (MTQ) D same as C; E [6220], New Caledonia (MNHN-IM- 2019 - 1598) F [6195], New Caledonia (MNHN-IM- 2019 - 1595) G same as F. Scale bars: 100 μm (A), 10 μm (B, G), 20 μm (C), 5 μm (D), 80 μm (E), 4 μm (F).

Figure 58. Accessory penial gland spine, Peronia sydneyensis A-C, G-I New Caledonia D, J Australia, New South Wales E, F, K, L Australia, Queensland A [6209] (MNHN-IM- 2019 - 1596) B [6213] (MNHN-IM- 2019 - 1597) C [6222] (MNHN-IM- 2019 - 1599) D holotype, [1516 H] (AM C. 468916.001) E [2661] (MTQ) F [2664] (MTQ) G same as A; H same as B; I same as C; J same as D; K same as E; L same as F. Scale bars: 100 μm (A-F), 10 μm (G-I, K), 6 μm (J, L).

Figure 104. Accessory penial gland spine, Peronia verruculata (unit 1) A Vietnam [5621] (ITBZC IM 00021) B Papua New Guinea [5469] (MNHN-IM- 2013 - 12010) C Vanuatu [5481] (MNHN-IM- 2013 - 62393) D New Caledonia [6214] (MNHN-IM- 2019 - 1593) E same as A; F same as B; G same as C; H same as D. Scale bars: 300 μm (A, B, D), 200 μm (C), 10 μm (E-G), 20 μm (H).

Figure 105. Accessory penial gland spine, Peronia verruculata (unit 2), Indonesia, Sumatra A, E [1797] (UMIZ 00180) B, F [1795] (UMIZ 00180) C, G [1796] (UMIZ 00180) D [1746] (UMIZ 00178). Scale bars: 300 μm (A-C), 10 μm (D-G).