Myxicola cf. sulcata Ehlers, 1912
Voucher specimens. Sea Lion: stations 67MFA and 25MFC; Inflexible: station 2MFB.
Diagnosis. Large, robust species; body covered by sheath, giving the body a smooth appearance (chaetae not clearly protruding from the body); body cylindrical, gradually tapering posteriorly, without clear division between thorax and abdomen; body segments narrow (much wider than long) and crowded throughout. The largest voucher specimen complete with branchial crown; body 35mm long, branchial crown 15mm long, body width 4mm, body curved into crescent-like shape, colour in alcohol dark yellow; the smallest voucher complete with branchial crown; body 4mm long, branchial crown 3mm long, body width 1 mm; body straight. Thorax with 8 chaetigers, abdomen with 22 or more chaetigers (depending on size).
Large voucher with 13 pairs of radioles fused at the base by a palmate membrane, ventral pair shortest; ventral filaments not observed.
Collar not developed; peristomium reduced dorsally and laterally to ring, ventrally elongated as a broad triangular lobe at the base of radioles; peristomial eyes not observed. Glandular ridge on chaetigers 2 present.
Peristomial chaetae narrowly limbate, arranged in longitudinal row. Thoracic notochaetae arranged as a tuft on very slender narrowly limbate chaetae; thoracic uncini not easily observable in specimens available here. Abdominal neurochaetae, thin capillaries; abdominal uncini very small (difficult to observe), forming nearly complete cinctures around the body, avicular with 2 large teeth.
Pygidium broad conical lobe, not obvious in large specimens; pygidial eyes not observed.
Remarks. Myxicola sulcata is a very distinct species, described from Ross Sea by Ehlers (1912) and considered to have distribution limited to that area (Knox and Cameron, 1998). Reports of this species outside the Ross Sea may represent a different species, however more work would be necessary to establish if FI represent a new species, distinct from M. sulcata.
