Leitoscoloplos abranchiatus (Hartman, 1967)
- GBIF Backbone Taxonomy
- Published in
- Mackie, Andrew S. Y. A review of species currently assigned to the genus Leitoscoloplos Day, 1977 (Polychaeta: Orbiniidae), with descriptions of species newly referred to Scoloplos Blainville, 1828. Sarsia, 72: 1-28. (1987).
Usage Conditions Apply
- Leitoscoloplos abranchiatus
Diagnosis. All specimens incomplete posteriorly. Longest fragment ~ 15 mm long, 1.3 mm wide, consisting of 41 chaetigerous segments. Thorax slightly flattened, abdomen cylindrical. Prostomium conical; one peristomial ring. Eleven thoracic chaetigers. Abdominal parapodia lateral in anterior abdomen, shifted dorsally on posteriorward segments. Branchiae from chaetiger 24, first short triangle, then becoming longer, strap-like. Thoracic postchaetal lobes conical in both rami; short in anterior thorax, becoming longer in middle and posterior parts; notopodial lobes longer. No subpodial or stomach papillae. Abdominal notopodia digitiform, same length as branchiae or shorter; abdominal neuropodia weakly bilobed, with short round lobes, inner slightly larger. Subpodial flange not developed, no flange papillae. All chaetae crenulated capillaries; forked chaetae not observed, probably broken. Colour in ethanol whitish-brown, with pigment spots on prostomium and in intersegmental furrows, or completely white.
Description. A small species, up to 18 mm long, 1.0 mm wide for about 30 setigerous segments. Prostomium conical, narrowly rounded on anterior margin (Fig. 6 A); peristomium deeply folded, with 2 – 3 superficial annuli. Thoracic region with 9 – 13 setigers. Thoracic parapodia with short, conical noto- and neuropodial postsetal lobes. Abdominal parapodia only weakly elevated dorsally; with short, fingerlike notopodial postsetal lobes; neuropodia flattened, prolonged, rectangular in shape, distally entire (Fig. 6 B). Thoracic parapodia with fascicles of long crenulated capillaries; abdominal notopodia with capillaries and 1 – 2 furcate setae, each with unequal tynes connected by row of thin needles (Fig. 6 C). Branchiae entirely absent. Pygidium unknown.
Remarks. This species was well described by Hartman (1967) and is illustrated here for the first time. Leitoscoloplos abranchiatus is readily differentiated from related forms by the numerous long, silky appearing capillaries of the thoracic region, the complete absence of branchiae, and abdominal parapodia that are lateral or only weakly elevated.
Distribution. Subantarctic and Antarctic seas, 1400 – 5338 m.
Material examined: Scotia Sea, West Scotia Basin, Falkland Islands, Eltanin Sta. 6 - 350, 2452 m, Menzies trawl (3, USNM 56455). — off Cape Horn, Eltanin Sta. 4 - 112, 20 Jul 1962, 55.52 ° S, 61.92 ° W, 4008 m, holotype and 7 paratypes, (USNM 55531 – 2). — off Tierra del Fuego, R / V Vema Sta. V- 17 - 56, 4006 m, (1, LACM-AHF Poly 5010) — South Shetland Islands, Eltanin Sta. 4 - 138, 1437 m (3, USNM 56454). — off South Georgia, Eltanin Sta. 9 - 711, 2983 – 3331 m (1, USNM 60630). — Drake Passage, Eltanin Sta. 9 - 740, 384 – 494 m (1, USNM 61944). — South Orkney Islands, Eltanin Sta. 6 - 1082, 298 – 302 m (1, USNM 60631). — Weddell Sea, Antarctica, Glacier Sta. 69 - 21, 2288 m (1, USNM 61945). — Weddell Sea, ANDEEP III ANT XXII- 3, R / V Polarstern, Sta. PS- 67 / 078 - 6, 2168 m (1, SEM, JAB); Weddell Sea, abyssal plain, ANDEEP SYSTCO ANT XXIV- 2, R / V Polarstern, Sta. 33 - 14, 5338 m, 6 specimens (ZMH P- 27794). — South Pacific Ocean, Albatross Cordillera, Eltanin Sta. 14 - 1250, 3638 – 3825 m (2, USNM 60632).
- Blake, James A. (2017). Polychaeta Orbiniidae from Antarctica, the Southern Ocean, the Abyssal Pacific Ocean, and off South America. <em>Zootaxa.</em> 4218(1): 1-145 [monograph]. 10.11646/zootaxa.4218.1.1
- Mackie, Andrew S. Y. 1987. A review of species currently assigned to the genus Leitoscoloplos Day, 1977 (Polychaeta: Orbiniidae), with descriptions of species newly referred to Scoloplos Blainville, 1828. Sarsia, 72: 1-28.