Eunice cultrifera, Zanol & Hutchings & Fauchald, 2020

Zanol, Joana, Hutchings, Pat A. & Fauchald, Kristian, 2020, Eunice sensu latu (Annelida: Eunicidae) from Australia: description of seven new species and comments on previously reported species of the genera Eunice, Leodice and Nicidion, Zootaxa 4748 (1), pp. 1-43 : 12-15

publication ID	https://doi.org/ 10.11646/zootaxa.4748.1.1
publication LSID	lsid:zoobank.org:pub:B9EC373A-DF9B-47E2-916C-CF211D8F0727
DOI	https://doi.org/10.5281/zenodo.3704697
persistent identifier	https://treatment.plazi.org/id/8C0D3355-C01D-D12C-33BC-FB82FBBF9AFE
treatment provided by	Plazi
scientific name	Eunice cultrifera
status	sp. nov.

Treatment

Eunice cultrifera View in CoL , new species

( Figs 5 View FIGURE 5 , 6 View FIGURE 6 , 7 View FIGURE 7 )

Material examined. New South Wales. Jervis Bay , 35°03.93’S, 150° 45.60’E, 20 m, sandy bottom AM GoogleMaps W.20544 (HOLOTYPE) parapodia 10, 50, 250, 360 removed and mounted for SEM ( AM W.20544.001) . PARATYPES, Jervis Bay , ACT, 35°03.93‘ S, 150° 45.60‘E, 20 m depth, flat sandy bottom CSIRO GoogleMaps Fisheries , 26 Feb 1991, AM W.20537 (l), AM W.20538 (l), AM W.20539 (l), AM W.20540 (1), AM W.20541 (l), AM W.20542 (l), AM W.20543 (l), AM W.20546 (l), AM W.20547 (1), AM W.20548 (l), AM W.20549 (l), AM W. 20550 (1), AM W.20551 (l), AM W.20552 (l), AM W.20553 (1), AM W.20554 (l), AM W.20555 (l), AM W.20556 (1), AM W.20558 (1) plus tube.

Queensland. Port Curtis , 23°55’S, 151°23’E, 20 m, AM GoogleMaps W.197115 (l).

Description. Holotype incomplete with 360 chaetigers; total length 300 mm; length through chaetiger 10 15 mm; maximum width 7 mm at chaetiger 10. Body dorsally inflated; parapodia, especially anteriorly, short. As preserved, bone-colored with no distinct color patterns.

Prostomium dorsally inflated and anteriorly rounded; depressed around palpal bases; bearing deep median sulcus ( Figs 5A, B View FIGURE 5 ; 6A View FIGURE 6 ). Antennae in straight line; palps directly anterior to lateral antennae. Ceratophores and palpophores short, ring-shaped. Ceratostyles and palpostyles tapering; irregularly articulated. Median antenna longest, but no antennae extending beyond peristomium. Eyes located between bases of lateral antennae and palps. Peristomium slightly flaring anteriorly; anterior ring 3/4 of total peristomial length; separation distinct ventrally and dorsally; less visible laterally, but visible around body. Peristomial cirri tapering; not extending beyond anterior peristomial ring; irregularly articulated.

Maxillary formula 1+1, 6+4, 7+0, 4+8, 1+1, 1+1 ( Fig. 5C View FIGURE 5 ). MxVI ridge-shaped. MxIII short; forming part of distal arc with left MxIV and V. Left MxIV running dorsal to ventral, teeth restricted to the dorsal quarter, and with basal plate along ventral half of the plate. Maxillary formula of paratype (AM W.20538) 1+1, 4+4, 7+0, 2+8, 1+1, 1+1 ( Fig. 6B View FIGURE 6 ). Mandibles missing calcareous cutting plate.

Branchiae present from chaetiger 50 to end of body (observed in complete paratypes, AM W.20554 complete but in 2 pieces; AM W.20556 complete but in 4 pieces). Most branchiae single, slightly flattened filaments; far posterior chaetigers with double similar filaments ( Figs 5J, N View FIGURE 5 ; 6F View FIGURE 6 ).

Anterior chaetal lobes obliquely truncate with acicula emerging near dorsal edge ( Figs 5D, I View FIGURE 5 ; 6D View FIGURE 6 ). Median chaetal lobes slightly obliquely truncate; higher at dorsal edge with acicula emerging above midline ( Fig. 5J View FIGURE 5 ). Posterior chaetal lobes becoming increasingly triangular ( Figs 5N View FIGURE 5 ; 6F, G View FIGURE 6 ). All prechaetal lobes low transverse folds. Anterior postchaetal lobes slightly longer than chaetal lobes, truncate; highest near dorsal edge of neuropodium ( Fig. 5D View FIGURE 5 ). Median and posterior postchaetal lobes low folds. Ventral cirri thick, triangular, distally blunt in anterior chaetigers; inflated bases start at chaetiger 5 becoming thick ventral ridges with short narrow tips at about chaetiger 10 ( Fig. 5D View FIGURE 5 ); posterior thumb-like from around chaetiger 150. Anterior notopodial cirri distinctly inflated near the base of styles; styles irregularly articulated and separated from cirrophores by distinct grooves. Posterior notopodial cirri short digitate with inflated bases, equal to length of parapodia with chaetae, lacking a cirrophore ( Figs 5N View FIGURE 5 ; 6F View FIGURE 6 ).

Limbate chaetae present in all chaetigers. Pectinate chaetae small, scoop-shaped with transverse distal edges, with slender shafts; distinctly flaring distally; one marginal tooth distinctly longer than other teeth ( Figs 5F, M, O View FIGURE 5 ; 6C, E View FIGURE 6 ). Anterior pectinate chaetae with up to 6–9 teeth. Median and posterior pectinate chaetae with up to 10–13 teeth. Shafts of compound chaetae distally slightly inflated ( Fig. 5E, H View FIGURE 5 ). Anterior and median chaetigers with compound spiniger chaetae; appendages triangular, knife-blade shaped distally slightly irregular ( Figs 5E, H View FIGURE 5 ; 6I View FIGURE 6 ). Posterior chaetigers with compound falciger chaetae, appendages bidentate with distal tooth erect, proximal tooth triangular, directed laterally with tip curved distally; guards rounded ( Fig. 6J View FIGURE 6 ). Internal notoaciculae present in all chaetigers; neuropodial acicula anteriorly and posteriorly single, medially double. All neuropodial acicula tapering to blunt tips; tip distally bent in posterior chaetigers ( Figs 5L View FIGURE 5 ; 6F, G View FIGURE 6 ). Aciculae and subacicular hooks have distinct dark cores and clear sheaths. Subacicular hooks with dark brown to black cores; with sharply tapered erect distal tooth and narrow, tapering proximal tooth, distinctly narrower at base than width of hook at that point ( Figs 5K View FIGURE 5 ; 6H, K View FIGURE 6 ). Subacicular hooks first present from chaetiger 90 in holotype; present in all chaetigers thereafter; always single.

Variation. Variation in number of chaetigers and length of complete individuals (Holotype, paratypes AM W.20554 and AM W.20556) is 360 chaetigers and 300 mm, 520 chaetigers and ˜ 290 mm, and 297 chaetigers and 130 mm respectively. Start of branchiae varies between chaetigers 40 to 55. Subacicular hooks are first present from chaetiger 50 to 97, being more posterior in larger specimens. On these specimens the ventral cirri become ventral thickened ridges at chaetiger 10 and around 120 and 145 chaetigers becoming digital in shape.

Type locality. Jervis Bay , New South Wales, 35°03.93’S, 150° 45.60’E GoogleMaps .

Habitat notes. Eunice cultrifera n. sp., lives in large complex tubes tubes or tube-systems forming masses on sandy bottom present in roughly 10–20 m depth ( Fig. 7 View FIGURE 7 ). Most of the materal comes from Jervis Bay.

Etymology. The species name, Latin for knife-bearer, refers to the shape of the appendage of the anterior compound chaetae.

Remarks. Compound chaetae with spinigerous appendages are present in E. cultrifera n. sp., E. impexa Grube, 1878 , E. taoi Hsueh & Li, 2014 , E. tubicola ( Treadwell, 1922) , E. tubifex Crossland, 1904 . In E. impexa and E. taoi the branchiae may have six to seven branchial filaments, respectively, in a palmate, often irregular arrangement, and pectinate arrangement, also both species have subacicular hooks lighter than aciculae and two hooks present in several chaetigers; E. tubicola has single branchial filaments terminating well before the posterior end, compound spiniger chaetae restricted to anterior most chaetigers, aciculae single and yellow; and E. tubifex has up to four branchial filaments present through a long body region and aciculae distally geniculated. All these differences clearly distinguish these previously described species from E. cultrifera n. sp. Both E. impexa and E. tubifex have been reported from Australia, but records of the latter are probably dubious as discussed below. Eunice cultrifera n. sp. probably belongs to the clade containing E. impexa and Eunice filamentosa Grube, 1856 in Zanol et al. (2014) . It shares with them the shape of prostomium, late start and shape of branchiae, inflated base of ventral cirri as thick ventral ridges, and left MxIV with teeth restricted to the dorsal portion of the plate.