Key to the Gulf of Mexico BLM-OCS Species of Heteropodarke 



la. Neurosetae of midbody region as thick, blunt, short-bladed falci- 

 gers (Figure 2S-12d,e). . Heteropodarke cf. heteromorpha, p. 28-15 



lb. Neurosetae of midbody region as slender, pointed, serrate falci- 

 gers (Figure 28-14d) Heteropodarke sp. A, p. 28-17 



Heteropodarke cf. heteromorpha Hartraann-Schroder, 1962 

 Figures 28-11, 12a-g 



Heteropodarke heteromorpha Hartmann-Schroder, 1962:118, pi. 5, fig. 30, 



pi. 6, figs. 31-34. 



Heteropodarke heteromorpha — Dorsey, 1978:32, fig. la-c. 



MATERIAL EXAMINED: 

 Gulf of Mexico BLM-OCS: 



S0?LA 20B-4/S1 (1 spec, USNM 90628), 20-7/81 (9 spec, USNM 71776); 

 MAFLA 2422D-7/76 (1 spec), 2422E-7/76 (1 spec), 2423D-7/76 (1 spec), 

 2424B-7/76 (8 spec), 2424D-7/76 (6 spec, USNM 90629), 2530A-6/75 (3 

 spec), 2640F-11/77 (1 spec), 2852D-8/77 (2 spec), 2960C-11/77 (1 

 spec.) . 

 DESCRIPTION: 



Length, 12.4+ mm (previously reported to 3.6 mm); width, to 0.6 mm (pre- 

 viously reported to 0.3 mm). Body slender, thread-like; all specimens 

 incomplete with up to 74 setigers. Prostomium rounded, with four smill 

 eyes in trapezoidal arrangement on posterior half (Figure 28-12a). 

 Antennae similar in length, pseudoarticulate, arising close together at 

 anterior edge of prostomium. Palps similar and arising ventrolateral to 

 antennae. Nuchal organs as paired ridges along postectal margins of 

 prostomium. Tentacular cirri pseudoarticulate, numbering six pairs 

 (questionably four or five pairs on a few specimens). First tentacular 

 segment not visible dorsally. Parapodia subbiramous (Figure 28-12b), 

 dorsal cirrophore with slender notoaciculu<n. Neuronodium supported by 

 stout aciculum. Dorsal and ventral cirri faintly to distinctly arti- 

 cled. Falcigers of first three setigers having shaft-heads with large, 

 hooked protuberance; and short, bluntly rounded blades (Figure 28-12c). 

 Falcigers becoming thick and golden in color, with blunt shaft-heads and 

 blades (Figure 28-12d,e), beginning on setiger 4 and continuing to 

 setigers 13-33 (number of setigers bearing thick falcigers increasing 

 with size of specimen). Subsequent falcigers more slender, with short, 

 light.ly serrate, hook-tipped blades (Figure 28-12f). Slender, lightly 

 serrate, composite spiniger (Figure 28-12g) present in all fascicles 

 from setiger 3. Pharynx with ten triangular marginal papillae; extend- 

 ing back to setigers 19-37, slightly beyond point where thick falcigers 

 are replaced by slender ones. One specimen with eggs in posterior 

 region from about setiger 50. 



REMARKS: These specimens differ from H. heteromorpha in having the 

 slender falcigers more highly modified, especially oa the first three 

 setigers. 



PREVIOUSLY REPORTED HABITAT: Fine to coarse sand, shell and stones, 3- 

 98 m. 



GULF OF MEXICO BLM-OCS OCCURRENCE: Numerous occurrences in northeastern 

 Gulf (Figure 28-11); 10-168 in; coarse to fine-very fine sand, silty fine 

 to very fine sand, sandy silt. 



28-15 



