Taxonomy
Streptosyllis bidentata (non Southern) Campoy 1982:314, pl. 25 a-j
Descriptions
Body without color, slender, tapering slightly towards anterior end and strongly towards posterior end. 2mm long, 0.17mm wide, for 30 chaetigers. Prostomium sligthtly wider than long, two pairs of eyes in trapezoidal arrangement, and two anterior eyespots. Antennae smooth, median one inserted between anterior pair of eyes, about twice as long as prostomium with palps, lateral antennae about half this size, inserted near anterior margin of prostomium. Palps small, with ventral pair of cushion-shaped lobes and pair of papillae. Ciliated band between peristomium and prostomium . Peristomium with pair of smooth tentacular cirri, in shape and length similar to lateral antennae, ventral ones shorter. Dorsal cirri club-shaped, smooth, in shape and length similar to lateral antennae. From mid-body smooth cirri alternate with pseudoarticulated cirri with granular inclusions. Ventral cirri digitiform. Parapodial lobes conical, shorter than cirri, with dosal ciliary band.
Parapodia with one dorsal simple chaeta, 7-11 compound chaeta and single acicula. Simple dorsal chaeta unidentate, slightly curved, serrated on margin. roundet tip in anterior chaetigers, from chaetiger 7 with hyaline hood.Simple chaeta of chaetigers 1-6 wider than in remaining chaetigers. Compound chaetae in first 6 chaetigers include 1-2 upper long-bladed bidentate serrated falcigers, and 5-8 stout, short-bladed falcigers. Shaft distally bifid.
From chaetiger 7 compound chaetae bidentate, with hooked distal teeth, and large proximal teeth, clearly separated from distal teeth, almost in a right angle. Blades serrated, dorso-ventral gradation in length with in fascicle. Ventral simple chaetae absent.
Aciculae distally knobbed, enlarged in chaetigers 2-6, about twice as thick as in remaining chaetigers.
Pygidium triangular with 3 anal cirri, pair of long lateral ones and a median appendix with cilia. Pharynx unarmed, with crown of papillae, extending from anterior end to chaetiger 4-5. Proventriculus extending through 5 segments.
Sexually mature male and female specimens with sexual products form chaetiger 12. Males with reddish- brown eyes and natatory chaetae.
S. campoyi is related to S. websteri and S. bidentata and differs mainly in having enlarged aciculae and modified chaetae in chaetigers 2-6 instead of in 2-5. The serration of the blades of the compound chaeate is also different.
Sources
Distribution
Ecology
Sexually mature specimens have been observed almost all year round.
S. campoyi is relatively stenotopic, collected at stations with low percentage of carbonates (2.9-7.5%). Vertical distribution up to 30cm at a station of medium sand with higer percentages of organic matter (1.5%).
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