SOME ASPECTS OF THE BIOLOGY OF DEEP-SEA LOBSTERS OF 



THE FAMILY POLYCHELIDAE (CRUSTACEA, DECAPODA) 



FROM THE WESTERN NORTH ATLANTIC ' ^ 



Elizabeth Lewis Wenner^ 



ABSTRACT 



Stereomastis nana was the most abundant species of Polychelidae collected by otter trawl on the 

 continental slope of the Middle Atlantic Bight, off the eastern United States. Total catches were almost 

 four times greater than those of its congener, S sculpta. Other polychelid species, Poiycheles ualidus 

 and P. granulatus, were caught infrequently . Si^reomasds nana was abundant at depths of 1,400-2,599 

 m, and S. sculpta occurred at 486-2,257 m. Stereomastis nana and S. sculpta appear to spawn year 

 round, and both may be deep-sea scavengers. 



The Polychelidae are the only extant members of 

 the superfamily Eryonoidea, a group represented 

 in fossil records from the mid-Triassic period 

 (Glaessner 1969; Firth and Pequegnat'*). The fam- 

 ily is currently placed by Glaessner (1969) within 

 the infraorder Macrura, along with the spiny 

 lobsters (Palinuridae) and the shovel-nosed 

 lobsters (Scyllaridae). Although the Polychelidae 

 are not of commercial importance, interest in 

 these lobsters dates back when Bate (1888) dis- 

 cussed uniqueness of the family because its mem- 

 bers lack eyes and are related to forms thought to 

 be extinct since the Mesozoic. In addition, some 

 species live at extreme depths. Since that time, 

 Andrews (1911) indicated the occurrence of exter- 

 nal spermatophores and discussed sperm transfer 

 among male and female polychelids; Santucci 

 (1933) and Bernard (1953) suggested that 

 Poiycheles typhlops performs reproductive migra- 

 tions up slope; and Firth and Pequegnat (see foot- 

 note 4) investigated taxonomic relationships of 

 the entire family Polychelidae as well as certain 

 aspects of its biology. 



Otter trawl collections of Polychelidae have 

 been made by the Virginia Institute of Marine 



'Based on part of a dissertation to be presented to the School of 

 Marine Science, College of William and Mary, Williamsburg, 

 Va. 



^Contribution No. 881, Virginia Institute of Mairine Science, 

 Gloucester Point, Va. 



'Virginia Institute of Marine Science, Gloucester Point, Va.; 

 present address: South Carolina Wildlife and Marine Resources 

 Department, P.O. Box 12559, Charleston. SC 29412. 



■•Firth, R.W., Jr., and W.E. Pequegnat. 1971. Deep-sea lob- 

 sters of the families Polychelidae and Nephropidae (Crustacea, 

 Decapodal in the Gulf of Mexico and Caribbean Sea. Texas 

 A&M Res. Found. Ref 71-1 IT, College Station, 106 p. 



Science on the continental slope near Norfolk 

 Canyon, off the eastern United States from 1973 to 

 1976, which confirmed their importance as 

 benthic slope crustaceans. In this paper, I give new 

 biological information on this interesting group of 

 decapods that has come to light as a result of these 

 collections. Species from the western North Atlan- 

 tic which are discussed include Po/yc/?e/<?s validus , 

 P. granulatus, Stereomastis nana, and S. sculpta 

 sculpta (distinguished from the Pacific form, S. 

 sculpta pacifia, by Firth and Pequegnat (see foot- 

 note 4), but referred to in this paper, for simplicity, 

 as S. sculpta ). 



METHODS AND MATERIALS 



Polychelidae were collected during eight sea- 

 sonal cruises from June 1973 to January 1976 in 

 the Middle Atlantic Bight (lat. 33°33'-38°52' N). 

 Tows were made either with a 13.7 m or 9.1 m 

 (headrope) semiballon four-seam otter trawl for 

 0.5 h at depths shallower than 2,000 m and 1 h in 

 water deeper than 2,000 m (see Musick et al.^ for 

 detailed gear description). A precision depth re- 

 corder determined mean depth of trawl every 3 

 min after the trawl hit bottom for 0.5-h tows and 

 every 6 min for 1-h tows. Bathythermographs or 

 reversing thermometers recorded bottom temper- 

 atures. Analyses of relative abundance did not 

 include samples from tows in which the net tore, 

 failed to reach bottom, or became twisted during a 



>Musick,J.A.,C A. Wenner, andO.R. Sedberry. 1975. Ar- 

 chibenthic and abyssobenthic fishes. In May 1974 baseline in- 

 vestigation of Deepwater Dumpsite 106, p. 229-269. NOAA 

 Dumpsite Eval. Rep. 75-1, 388 p. 



Manuscript accepted December 1978. 

 FISHERY BULLETIN: VOL. 77, NO. 2, 1979. 



435 



