3b. Ventral cirri present from setiger 3; median antenna present or 

 absent 4 



4a. Median antenna absent (Figure 29-16a); notopodial hooks present 

 from setiger 6 Ancistrosyllis sp. C, p. 29-19 



4b. Median antenna present (Figures 29-18a, 20a); notopodial hooks 

 present from setiger 3 or 6 5 



5a. Notopodial hooks present from setiger 6 



Ancistrosyllis jonesi, p. 29-19 



5b. Notopodial hooks present from setiger 3 6 



6a. Transverse dorsal ridges present (Figure 29-20c) 



Ancistrosyllis papillosa, p. 29-22 



6b. Transverse dorsal ridges absent (Figure 29-22a) 



Ancistrosyllis hartmanae, p. 29-24 



Ancistrosyllis sp. A 

 Figures 29-9, lOa-i 



MATERIAL EXAMINED: 

 Gulf of Mexico BLM-OCS: 



SOFLA 12B-4/81 (1 spec, USNM 86926), 24B-4/81 (1 spec, USNM 

 86927), 33C-8/81 (2 spec, USNM 86928); MAFLA 22121-8/77 (1 spec, USNM 

 86925), 2212H-2/78 (1 spec, USNM 86924), 2313E-11/77 (1 spec), 25361- 

 7/76 (1 spec); STOCS HR3-6 Sp/76 (1 spec, USNM 86929). 

 DESCRIPTION: 



Length, to 8.0 mm; width, to 0.75 mm. Largest specimen complete with 42 

 setigers and two achaetous preanal segments. Prostomium (Figure 29-10a) 

 with lateral antennae nearly as long as tentacular cirri; median antenna 

 two-thirds length of lateral ones. Palps with small palpostyles, not 

 visible dorsally. Tentacular cirri (Figure 29-10b) equal in length to 

 dorsal cirri of setiger 2. Dorsal cirri of setiger 1 almost twice as 

 long as subsequent ones. Ventral cirri present from setiger 1, well- 

 developed, extending slightly beyond setigerous lobes (Figure 29-10c). 

 Prostomium and palps heavily papillose dorsally; segments with few 

 papillae dorsally; ventrum mostly smooth. Hooked acicular notosetae 

 beginning on setiger 3, accompanied by slender notoaciculum (Figure 29- 

 10c). Neurosetae with curved tips and thin subapical tooth (Figure 29- 

 lOd-g). Middle setigers with additional large bifid neurosetae (Figure 

 29-10h), usually numbering one per parapodium. Posterior end with 2-3 

 aciiaetous preanal segments. Pygidium (Figure 29-10i) with moderately 

 long papillae and a pair of papillose anal cirri. Proboscis (Figure 29- 

 10b) with irregularly arranged papillae having weakly chitinized tips. 

 REMARKS: Ancistrosyllis sp. A is similar to A. groenlandica Mcintosh, 

 1879, but differs from the latter in having notopodial hooks beginning 

 on setiger 3 instead of setigers 4-6. Ancistrosyllis sp. A is also 

 similar to A. matsunagaensis (Kitamori, 1960), from which it differs in 

 being less papillose, in having shorter head and parapodial appendages, 

 and in possessing a relatively large seta in the neuropodia. A. hamata 

 (Hartman, 1960) has a proboscis similar to Ancistrosyllis sp. A, but has 

 notopodial hooks from setiger 6 instead of 3. 



29-14 



