Levidorum scotarium Hartman 1967

Levidorum scotarium Hartman, 1967 (Fig. 39A–B) Levidorum scotarium Hartman, 1967: 84, pl. 28; Perkins 1987: 163 –166, figs 1A–D, 2A–D. Material examined . USA : holotype USNM 55525, Scotia Sea, 59°50'– 59°52'S 32°27'– 32°23'W, 650–659 m, station 1058, 4 Apr 1964. Diagnosis . Larg...

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Bibliographic Details
Main Author: Nygren, Arne
Format: Other/Unknown Material
Language:unknown
Published: Zenodo 2004
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Online Access:https://doi.org/10.5281/zenodo.6273212
http://treatment.plazi.org/id/03CDB626CC2D4E7BFEE878578B82830D
Description
Summary:Levidorum scotarium Hartman, 1967 (Fig. 39A–B) Levidorum scotarium Hartman, 1967: 84, pl. 28; Perkins 1987: 163 –166, figs 1A–D, 2A–D. Material examined . USA : holotype USNM 55525, Scotia Sea, 59°50'– 59°52'S 32°27'– 32°23'W, 650–659 m, station 1058, 4 Apr 1964. Diagnosis . Large Levidorum with palps, prostomium divided by a transverse furrow, simple hooked unidentate chaetae. Description . Holotype incomplete in two fragments, length 12 mm for 38+16 chaetigers, width 1.5 mm at chaetiger 10. Preserved material without colour markings. Body stout. Ciliation not observed. Prostomium divided dorsally by a median furrow (Fig. 39B), anteroventrally with two small palps (Fig. 39A). Palps free or basally fused, difficult to assess. Eyes absent (Fig. 39A, B). Nuchal epaulettes absent. All appendages absent (Fig. 39A, B). Parapodial lobes conical (Fig. 39A), small. Unknown number of aciculae in anterior chaetigers, 3 in median chaetigers. Chaetal fascicle with c. 8 chaetae in anterior fragment, 4–5 in posterior fragment. All chaetae simple unidentate, hook­like, with denticulation at base (Perkins 1987: fig. 2E). Bayonet chaetae not found, possibly absent. Pharynx with 1 sinuation but it seems to be distorted. Trepan in chaetiger 2–3 with 5 long teeth, absence/presence of basal ring and infradental spines not possible to determine. Proventricle lost. Pygidium lost. Reproduction . Not known. Habitat . 650 m. Distribution . North West Atlantic, Gulf of México. Only known from type locality. Remarks . Levidorum scotarium is the largest Levidorum ­species. In contrast with other Levidorum there are two small cushion­like structures anteroventrally on the prostomium, here interpreted as rudimentary palps; further, the prostomium is dorsally divided by a transverse furrow, absent in other Levidorum . Finally, the chaetae in L. scotarium are quite distinct from those found in other Levidorum ­taxa. Published as part of Nygren, Arne, 2004, Revision of Autolytinae (Syllidae: Polychaeta)., pp. 1-314 in Zootaxa 680 on pages ...