DESCRIPTION: 



Length, to 14.0 mm (previously reported to 50 mm); width, to 0.6 mm 

 (previously reported to 1 mm). Body slender; complete specimens with up 

 to 88 setigers. Two black, dorsal, transverse stripes per segment 

 anteriorly. Prostoraiutn octagonal to rounded, with four small, lentiger- 

 ous eyes (Figure 30-112a). Median antenna arising between anterior 

 eyes, with 7-22 articles; lateral antennae with 7-12 articles. Palps 

 triangular, broad basally, rounded distally. Dorsal tentacular cirri 

 with 8-20 articles, ventral ones with 6-12 articles. Dorsal cirri with 

 7-24 articles anteriorly, 5-16 articles medially. Ventral cirri digi- 

 tiform, not extending beyond parapodia. Pygldium with paired, lateral 

 anal cirri having 6-13 articles, and short midventral cirrus. Anterior 

 setae entirely composite bidentate falcigers (Figure 30-112b,c), re- 

 placed abruptly in larger specimens by thick, simple, ypsiloid setae 

 (Figure 30-112d) between setigers 14 and 21. Few transitional, pseudo- 

 composite setae (Figure 30-112e) sometimes present in smaller specimens. 

 Posterior setae as composite bidentate falcigers (Figure 30-112f), plus 

 slender, minutely bidentate superior and inferior simple setae (Figure 

 30-112g,h). Blade-length ratios 1.5-4.7:1 anteriorly, 1.1-2.4:1 poste- 

 riorly. Pharynx extending to setigers 6-10; margin smooth and surround- 

 ed by ten soft papillae; middorsal tooth subterminal. Proventricle 

 extending from setigers 6-11 to 9-16, with 39 (35-45) muscle cell rows. 

 Ventricle occupying two setigers. Pharynx about 1-1.5 times longer than 

 proventricle; proventricle about 2.5-3.5 times longer than wide. 

 PREVIOUSLY REPORTED HABITAT: Low water to 235 m; among ascidians, 

 algae, serpulid tubes, rocks, barnacles, oysters, hydroids, broken 

 shells; on pilings. 



GULF OF MEXICO BLM-0CS OCCURRENCE: Numerous records off Florida and one 

 station off Texas (Figure 30-111); 11-75 m; coarse to fine-very fine 

 sand, silty fine to very fine sand. 

 DISTRIBUTION: Cosmopolitan in temperate and tropical seas. 



Subgenus Ehlersia Langerhans, 1879 



TYPE SPECIES: Syllis sexoculata Ehlers, 1864. 



REFERENCE: 



Fauchald, 1977a:82. 



DIAGNOSIS: Modified simple and pseudocomposite setae absent. Superior 



composite setae elongate, spinigerous or spiniger-like, with blades at 



least five times longer than blades of inferior setae. 



REMARKS: The long-bladed setae of this subgenus have routinely been 



called spinigers, although in some species the blade tips are not 



pointed but are knobbed or minutely bidentate. The subgenus may be more 



precisely defined based on relative blade lengths, as above. 



Key to the Gulf of Mexico BLM-OCS Species of Syllis ( Ehlersia ) 



la. Spiniger-like setae with minutely knobbed tips (Figure 30-114b); 

 proventricle 4-8 times longer than wide, with more than 33 rows of 

 muscle cells Syllis (Ehlersia) cornuta, p. 30-120 



lb. Spiniger-like setae with minutely bidentate tips (Figures 30-116d, 

 118b); proventricle 1.5-4.4 times longer than wide, with fewer 

 than 33 rows of muscle cells 2 



30-118 



