Taxonomy
Descriptions
Body colorless, 4mm long, 0.25mm wide, for 42 chaetigers. Prostomium with two eyes in trapezoidal arrangement and two anterior eyespots. Anterior and posterior margin of prostomium ciliated. Antennae smooth, club-shaped. Lateral antennae inserted near anterior margin behind eyespots, about the length of prostomium and palps together, median antenna inserted in middle of prostomium, about twice as long as lateral antennae. Palps fused at bases, broad, directed ventrally, with long distal papilla each. Peristomium with two pairs of tentacular cirri, dorsal pair in shape and length similar to lateral antennae. Ventral pair slightly shorter. Dorsal cirri with ciliated bases, anteriorly smooth, similar to lateral antennae. From mid-body onwards smooth cirri alternating with pseudoarticulated cirri with granular inclusions. Pseudoarticulated cirri longer than smooth ones. Ventral cirri long, bases broad, long acute tips, longer than parapodial lobes and chaetae.
First chaetiger with dorsal simple chaeta, distally blunt, 1-2 compound unidentate spinigerous compound chaetae, and 7-8 unidentate short and slender falcigers. All blades with hyaline hood on margin. Shafts distally bifid.
Chaetigers 2-6 with solitary dorsal simple chaeta, wider than in
chaetiger 1; 1-2 compound spinigers similar to those in chaetiger 1 and
7-8 compound homogomph falcigers with very short, unidentate, blunt
blades. No hyaline hood on margin of falcigers.
From chaetiger 7, compound chaetae similar to those in chaetiger 1 but with longer blades. 1-2 spinigers with long blades and 3-5 falcigers with blades distally blunt. Dorsoventral gradation of blades in length within fascicle.
Dorsal simple chaetae slender, with long hyaline hood distally.
Aciculae distally truncated, strongly enlarged in chaetigers 2-6.
Pygidium with two lateral anal cirri, pseudoarticulated with granular inlcusions and a short median appendix. Pharynx through 4-5 segments, proventriculus through 5-6 chaetigers, with 40 muscular rows.
Mature males with sexual products from chaetiger 11, with natatory chaetae.
S. arenae , S. magnapalpa and S. templadoi are the only species of the genus with hyaline hood on the blades. The shape of the chaetae is different in all these species though. In S. arenae the hood is small and apical, in S. templadoi it goes all along the length of the blade. In S. magnapalpa only a few blades are provided with a hood.
Sources
Distribution
Ecology
Mature individuals have been collected in July, September, November, December; juveniles in September.
S. templadoi is a relatively stenotopic species, it was collected at stations with nitrogen of 0.03%. Vertical distribution 0-5cm.
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