Orbiniella abyssalis, Blake, 2020

Blake, James A., 2020, New species and records of deep-water Orbiniidae (Annelida, Polychaeta) from the Eastern Pacific continental slope, abyssal Pacific Ocean, and the South China Sea, Zootaxa 4730 (1), pp. 1-61 : 38-40

publication ID


publication LSID


persistent identifier


taxon LSID


treatment provided by


scientific name

Orbiniella abyssalis

new species

Orbiniella abyssalis new species

Figures 18–19 View FIGURE 18 View FIGURE 19


Material examined. North Equatorial Pacific Ocean, abyssal plain, Clarion-Clipperton Fracture Zone, NOAA

BIE Project site, coll. D. T. Trueblood. Sta. DDT-05-93, veg. 20, 2– 5 cm fraction, 13 Aug 1993, 12°56.566′N, 128°35.408′W, 4870 m, holotype ( USNM 1594176 View Materials ) GoogleMaps ; Sta. DDT-07-93, veg 24, 0–2 cm fraction, 02 Sep 1993, 12°56.303′N, 128°35.311′W, 4844 m, 1 specimen ( USNM 1594177 View Materials ) GoogleMaps ; Sta. DDT-11-93, veg. 22, 0–2 cm fraction, 04 Sep 1993, 12°56.055′N, 128°35.695′W, 4859 m, paratype ( USNM 1594178 View Materials ) GoogleMaps ; Sta. DDT-12-93, veg. 6, 0–2 cm fraction, 04 Sep 1993, 12°56.329′N, 128°35.698′W, 4851 m, paratype ( USNM 1594179 View Materials ) GoogleMaps ; Sta. DDT-08-94, 29 Jul 1994, 12°55.020′N, 128°35.400′W, 4880 m, 1 specimen ( USNM 1594180 View Materials ) GoogleMaps .

Description. Holotype elongate, of moderate size, mostly complete in two parts, 8.0 mm long, 0.7 mm wide for 65 setigers. Paratype (USNM 1594178) incomplete, 17 setigers, 1.35 mm long, 0.275 mm wide. All segments short, crowded, about eight times wider than long ( Fig. 18A View FIGURE 18 ). Body with similar segments throughout, lacking a separate thorax and abdomen. Body dorsoventrally compressed, without dorsal or ventral longitudinal grooves. Parapodia all lateral, not shifted dorsally in posterior segments. Each segment separated from following by an intersegmental area formed of 2–3 narrow raised annulae. Color in alcohol: light tan.

Pre-setiger region short, narrower than anterior setigers, merging with setiger 1 ( Fig. 18A View FIGURE 18 ). Prostomium short, broadly rounded anteriorly ( Fig. 18A View FIGURE 18 ); eyespots absent; nuchal organs low mounds on sides of posterior prostomium ( Fig. 18A View FIGURE 18 ). Peristomium a single large ring, longer than setiger 1, with one weakly defined lateral groove, not crossing dorsum or producing separate rings ( Fig. 18A View FIGURE 18 ).

Setiger 1 and following segments separated from one another by intersegmental groove with narrow annular rings. Branchiae entirely absent. Noto- and neuropodia formed as elongate lobes, tapering to rounded apex ( Fig. 18B View FIGURE 18 ). Notopodia with short, clavate postsetal lamellae ( Figs. 18B View FIGURE 18 , 19A View FIGURE 19 ); neuropodial postsetal lamellae absent. Notopodia with numerous long capillaries and 1–2 large, elongate acicular spines projecting well beyond parapodia ( Figs. 18C View FIGURE 18 , 19 View FIGURE 19 A–B); neuropodia with one large elongate acicular spine and numerous long capillaries; furcate setae absent. Spines thick, smooth, narrowing to pointed tip, some spines with slight curvature where narrowing begins ( Figs. 18C View FIGURE 18 , 19B View FIGURE 19 ). Capillaries not camerated, with minute bristles or barbs poorly developed; setae appearing smooth at 400x; bristles observed only at 1000x.

Pygidium not observed.

Methyl Green stain. No pattern, body stains uniformly, de-stains rapidly.

Remarks. Orbiniella abyssalis n. sp. is similar to three other deep-sea congeners: O. andeepia Narayanaswamy & Blake, 2005 , from Antarctica, O. petersenae Parapar, Moreira & Helgason, 2015 from the NE Atlantic, and O. tumida n. sp. from the California continental slope, in having a notopodial postsetal lamella and acicular spines in both noto- and neuropodia. Orbiniella abyssalis n. sp. differs from the other three species in having an unusually short and broad prostomium followed by a long, thick peristomium composed of a single ring, but with a weak lateral groove that does not cross the dorsum; the other species have two distinct peristomial rings. In addition, the noto- and neuropodial spines of O. abyssalis n. sp. are unusually long, about half as long as the capillaries. The spines of the other species are considerably shorter than the capillaries. The notopodial postsetal lamella is short and clavate in both O. abyssalis n. sp. and O. tumida n. sp. and longer and digitate in O. andeepia and O. petersenae . More details of these species and others are presented in Table 2 in View TABLE 2 the Discussion.

Etymology. The epithet is derived from the Latin abyssus, in reference to the deep-sea habitat of the species.

Distribution. Abyssal Pacific Ocean, 4844–4880 m.


National Oceanic and Atmospeheric Administration


Instituto di Entomologia


Tavera, Department of Geology and Geophysics











GBIF Dataset (for parent article) Darwin Core Archive (for parent article) View in SIBiLS Plain XML RDF