Odontosyllis polycera ( Schmarda, 1861 )

Rodríguez, Yolanda Lucas, Martín, Guillermo San & Fiege, Dieter, 2019, A new species and nine new records of Syllidae (Annelida) from the Socotra Archipelago (Indian Ocean), Zootaxa 4651 (2), pp. 235-258 : 250-251

Odontosyllis polycera ( Schmarda, 1861)

Figure 10

Syllis polycera Schmarda, 1861: 72 , pl. 28, fig. 219.— Augener, 1927: 152.— Day, 1967: 260, fig. 12.— Hutchings & Murray, 1984: 32.— Hartmann-Schröder, 1984: 20; 1985: 68, figs. 14–17; 1986: 41; 1989: 25; 1990: 51.

? Odontosyllis suteri non Benham, 1915.— Haswell, 1920: 107.

Odontosyllis polycera San Martín & Hutchings, 2006: 58 , figs. 19A, B, 25E, F, 35A–F, 36A–F.

Material examined Socotra, Qataninh Bay ,12º21’293N 53º32’659E, under stones and coral rubble, 8–11 m, 09.04.2000, 1 specimen broken in three pieces (including 3 permanent slides with pharynx and proventricle dissected) ( SMF 24991) .

Description. Body broad, with short, compressed segments. Specimen complete, broken in three pieces, about 142 chaetigers, pygidium present, probably in regeneration. Body white to yellowish in alcohol, without colour pattern, 24.5 mm long, 1.08 mm wide. Dorsally convex, ventrally more or less flattened. Prostomium oval, with two pairs of large, dark purple eyes in open trapezoidal arrangement; antennae short, small. Palps fused, bent ventrally. Dorsal tentacular cirri slightly longer than antennae, similar in length to body width, ventral tentacular cirri distinctly shorter than dorsal ones. Peristomium compressed, covered with a large occipital flap covering almost all prostomium. Antennae, tentacular, and dorsal cirri long, smooth to rugose. Dorsal cirri alternating long and short, becoming shorter posteriorly; long dorsal cirri in midbody slightly shorter than body width, short dorsal cirri approximately half the length of long ones; long dorsal cirri on most anterior segments slightly longer than body width. Ventral cirri shorter than parapodial lobes, globular and tough ( Fig. 10C ). Compound chaetae similar along body, with spinose shafts, blades short, thick, hooked, bidentate, teeth well separate. Short spines on margin and thin spines in tendon ( Fig. 10A ). Marked dorso-ventral gradation in size, being shorter dorsally and becoming longer as more ventral ( Fig. 10A, C ); most dorsal blades with both teeth very similar, remaining blades with short, small proximal tooth. Median blades about 9–28 μm, approximately 12 chaetae in midbody fascicle. Midbody parapodia with three slender aciculae two of them with rounded tip and smallest with trilobed tip ( Fig. 10B ). Pharynx short, through about five segments, 0.75 mm long, 0.6 mm wide with 5 teeth and 2 lateral plates ( Fig. 8D ). Proventricle 2.5 mm long, 0.8 wide, with 70 rows of muscular cells ( Fig. 8D ).

Remarks. This species has been reported in many different areas of the world (see below) at different depths ( San Martín & Hutchings 2006). Molecular studies should be conducted to understand the variability and distribution of this species. The specimen under study presents oocytes in midbody parapodia ( Fig. 10C , arrows).

Habitat. Occurring in sand, mud, algae, calcareous substrata, bryozoans, sponges, from intertidal to 90 m ( San Martín & Hutchings 2006). Under stones and coral rubble in the intertidal.

Distribution. Angola, Namibia, South Africa, USA (Southern California), Panamá, Indo-Pacific, New Zealand, Australia (Queensland, New South Wales, Tasmania, South Australia, Western Australia) ( San Martín & Hutchings, 2006).

Figures

FIGURE 8. Trypanosyllis richardi Paratype (SMF 24986); A anterior end, dorsal view; B pharynx and proventricle; C pharynx papillae and trepan detail. Odontosyllis polycera (SMF 24991); D pharynx and proventricle.

FIGURE 10. Odontosyllis polycera (SMF 24991); compound chaetae; A midbody; aciculae, B midbody; C oocytes (arrows).