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



la. Trepan with two large lateral teeth separating dorsal and ventral 



arcs of smaller teeth (Figure 30-4d) 



Autolytus dentalius, p. 30-12 



lb. Trepan with all teeth similar in size (Figure 30-6d) 



Autolytus sp. A, p. 30-15 



Autolytus dentalius Imajima, 1966 

 Figures 30-3, 4a-d 



Autolytus dentalius Imajima, 1966:36, fig. 7i-l. 



Autolytus dentalius — Day, 1973:35. 



Autolytus dentalius — Gardiner, 1976:127, fig. lOa-d. 



MATERIAL EXAMINED: 

 Gulf of Mexico BLM-OCS: 



SOFLA 4D-5/81 (1 spec, USNM 75267), 16A-4/31 (2 spec, USNM 75268), 

 16D-4/81 (1 spec, USNM 75269), 18B-4/81 (2 spec, USNM 75270), 24F- 

 11/80 (2 spec), 24C-8/31 (1 spec, USNM 75271); MAFLA 2211C-7/76 (1 

 spec), 2211E-7/76 (1 spec), 2211H-8/77 (2 spec), 2315A-8/76 (1 

 spec), 23131-11/77 (2 spec), 2528A-6/75 (2 spec), 2531C-8/77 (1 

 spec), 2534G-6/75 (1 spec), 2640-2/78 (1 spec, USNM 55817), 2854E- 

 8/77 (2 spec), 2958K-11/77 (1 spec). 

 Supplementary Material: 



Florida--IIutchinson Island, St. Lucie Co., 10.9 m, T. Perkins ID. (1 

 spec, USNM 54471). 

 DESCRIPTION: 



Length, to 8.0 mm (previously reported to 13 mm); width, to 0.5 mm. 

 Body small, slender; one complete specimen with 55 setigers plus three 

 achaetous preanal segments. Preserved material generally lacking pig- 

 mentation; one specimen with dorsal segmental transverse brown stripes. 

 Prostomiura rounded. Two pairs of large, lentigerous eyes, each pair 

 contiguous (Figure 30-4a); ocular spots occasionally present. Nuchal 

 epaulettes extending to setigers 3-4. Antennae, tentacular cirri, and 

 first two pairs of dorsal cirri extremely long, fairly broad. Dorsal 

 cirri of following segments alternating in length, ranging from 0.5-1.5 

 times as long as body width. Cirrophores of long dorsal cirri generally 

 equal to or longer than styles. Anal cirri not observed. Composite 

 falcigers having short blades, with distal tooth smaller than subdistal 

 tooth (Figure 30-4b). Superior bayonet-seta (Figure 30-4c) first pres- 

 ent from setigers 3-12 (usually setiger 8). Trepan of pharynx with two 

 slightly larger lateral teeth separating dorsal arc of 10-1 1 small teeth 

 from ventral arc of 15-20 small teeth (Figure 30-4d). Proventricle 

 located in setigers 10-13, with 23-36 indistinct muscle cell rows. 

 REMARKS: A. dentalius is newly reported from the Gulf of Mexico. 

 PREVIOUSLY REPORTED HABITAT: Intertidal to 10 m; shelly sediments. 

 GULF OF MEXICO BLM-OCS OCCURRENCE: Widespread in northeastern Gulf 

 (Figure 30-3); 19-120 m; coarse to very fine sand, silty fine sand. 

 DISTRIBUTION: Japan, North Carolina, Gulf of Mexico. 



30-12 



