GULF OF MEXICO BLM-OCS OCCURRENCE: Common In northeastern Gulf (Figure 

 30-103); 10-189 m; coarse to fine-very fine sand, silty fine to very 

 fine sand, clayey sandy silt, silty clay. 

 DISTRIBUTION: Cosmopolitan. 



Genus Geminosyllis Imajima, 1966 



TYPE SPECIES: Trypanosyllis ( Trypanose ta ) ohma Imajima and Hartman, 



1964. 



REFERENCES: 



Imajima, 1966:233. 



Fauchald, 1977a:82. 



DIAGNOSIS: Prostomium with three antennae. Two pairs of tentacular 



cirri. Antennae, tentacular, and dorsal cirri articled. All setae 



simple. Anterior margin of pharynx denticulate. 



Geminosyllis sp. A 

 Figures 30-105, 106a-c 



MATERIAL EXAMINED: 

 Gulf of Mexico BLM-OCS: 



MAFLA 22UG-7/76 (3 spec, USNM 65674; 6 spec). 

 DESCHIPTION: 



Length, to 5.5 mm; width, 0.5 mm. Body slender, cylindrical; complete 

 specimens with up to 39 setigers. Prostomium oval, with four small, 

 lentigerous eyes (Figure 30-106a). Median antenna with 12-19 articles, 

 lateral antennae with 10-11 articles. Palps thick, blunt, slightly 

 longer than prostomium. Dorsal tentacular cirri with 13-15 articles, 

 ventral ones with 8-9 articles. Anterior dorsal cirri with 8-23 arti- 

 cles, first pair longest; medial dorsal cirri usually alternating in 

 length, with short cirri having 1-4 articles and long ones having 3-8 

 articles. Ventral cirri digitiform anteriorly, becoming ovoid and smal- 

 ler posteriorly; not extending beyond parapodia. Anal cirri long, 

 smooth, with 2-3 articles. Setae all simple, bifid terminally, with a 

 large boss subterrainally (Figure 30-106b). Acicula numbering 2-3 per 

 parapodium anteriorly, 1-2 posteriorly; slightly knobbed or bent distal- 

 ly, not enlarged or strongly hooked (Figure 30-106c). Pharynx extending 

 to setigers 5-7, with 9-10 marginal papillae, and denticulate margin 

 having 9-10 bluntly rounded, chitinized teeth; middorsal tooth apparent- 

 ly absent. Proventricle extending from setigers 6-8 to 9-11, with 32 

 (29-34) muscle cell rows. 



REMARKS: This genus is newly reported from the Gulf of Mexico. Gemino- 

 syllis sp. A is similar in appearance to Haplosyllis spongicola , but 

 differs from the latter in having a denticulate pharyngeal margin, 

 slender and distally knobbed acicula, and a shorter proventricle. Gemi- 

 nosyllis sp. A differs from G. ohma (Imajima and Hartman, 1964) from 

 Japan, in having shorter antennae, tentacular and dorsal cirri, pharynx 

 and proventricle; and in lacking the additional middorsal pharyngeal 

 tooth. 



GULF OF MEXICO BLM-OCS OCCURRENCE: One station off central Florida 

 (Figure 30-105); 43 m; coarse sand. 



30-111 



