Eusyllis nuchalata Hartmann-Schröder, 1965

Brusa, Vivian S., Aguado, M. Teresa, Martín, Guillermo San & Rouse, Greg, 2013, Revision of the genus Eusyllis Malmgren, 1867 (Annelida: Phyllodocida: Syllidae: Eusyllinae), with the description of a new species from the eastern Pacific Ocean, Zootaxa 3599 (1), pp. 37-50 : 47-48

Eusyllis nuchalata Hartmann-Schröder, 1965

( Fig. 5 A–C)

Eusyllis nuchalata Hartmann-Schröder, 1965: 115 –118 Figs. 76–79.

Material examined. ZMUH P- 14586, three fragmented, incomplete paratypes.

Re-description. Body fragile, all specimens fragmented. Prostomium ovate, wider than long. Palps large and relatively short, triangular, separated at basis, ventrally folded. Nuchal organs semicircular, extending laterally over prostomium. Tentacular segment semicircular, shorter than subsequent segments, dorsally covering posterior part of prostomium. Antennae, tentacular cirri and dorsal cirri filiform, very slightly and indistinctly articulated on anterior part of body, smooth and short from midbody ( Fig. 5 A). Cirrophores well developed ( Fig. 5 A). Parapodia ovate, with two distal lobes ( Fig. 5 A, 5B). Ventral cirri ovate ( Fig. 5 A). Compound heterogomph chaetae, about six to seven per parapodium. Blades of dorsal chaetae slender, distinctly bidentated, both teeth similar, with short spines on margin, becoming wider ventrally, with proximal tooth more prominent and somewhat longer than distal ones. Remaining chaetae slight dorso-ventral gradation in length, 20 µm above, 30 µm below. Two or three aciculae per parapodium, slender, distally pointed ( Fig. 5 C). Pharynx with an incomplete denticled arc, with about 15 relatively large, conical teeth, and a conical anterior mid-dorsal pharyngeal tooth (fide Hartmann-Schröder, 1965).

Distribution. Pacific Ocean. Concepción, Corcovado Gulf, Chile ( Hartmann-Shröder 1965). Habitat. Fine sand with stones and detritus.

Figures

FIGURE 5. Eusyllis nuchalata (Paratype) (A) parapodia and cirri; (B) parapodia, dorsal view; (C) compound chaetae. Scales: (A – B) 0. 18 mm, C 20 µm.