KISHKKY BL'l.LKTIN: VOL 



be the most abundant polychelid collected by 

 benthic skimmer in the Gulf of Mexico, and Firth 

 and Pequegnat confirmed it as the most commonly 

 caught polychelid both in that region and in the 

 Caribbean Sea. Although Firth and Pequegnat 

 stated thatS. sculpta is one of the most commonly 

 reported species in the Polychelidae and probably 

 one of the most important polychelid species nu- 

 merically on the continental slope, it was much 

 less abundant thanS. nana in my Middle Atlantic 

 Bight collections (Figure 1 1. Abundance data 

 based on 13.7 m otter trawl catches showed S. 

 sculpta constituted 6. 5''f of the total benthic deca- 

 pod catch. Its importance diminishes at lesser and 

 greater depths within its bathymetric range of 486 

 (5.7' C) to 2,257 m (2.9" C). Analysis of variance 

 showed no significant difference in abundance by 

 depth intervals for 115 S. sculpta (Table 1). 



The overall ;' : 9 ratio (1:1.1) and se.\ ratios for 

 depths of capture did not differ significantly from 

 1:1 (Tables 2, 3). There was also no apparent rela- 

 tionship between average size of S. sculpta and 

 depth of capture (F = 2.321, df = 2,122, P =0.05). 



Ovigerous females (mean = 54 mm) were sig- 

 nificantly larger (Table 4) than males (mean = 32 

 mm I and other females (mean = 35 mm), based on 

 analysis of variance and Scheffe's multiple mean 

 comparison. 



Spermatophores occurred only on females 45 

 mm and larger and were found protruding from 

 the gonopores of males 32 mm and larger. Oviger- 



ous females were 45 mm and larger, and all had 

 attached spermatophores (Figure 7). Ovigerous 

 females and most males and females with exter- 

 nally located spermatophores were found at the 

 shoaler depths sampled; none were obtained below 

 1,199 m. 



Ovarian development stages of .S. sculpta were 

 similar to those described for.S. nana. Immature 

 gonads were found in all nonovigerous females in 

 = 36) 36 mm and larger. Ripening and gravid 

 individuals occurred only at sizes 38 mm and 

 larger. Seven ovigerous females were spent, and 

 one 54 mm individual was ripening. 



Since ovigerous females were obtained each 

 month, except July (Table 6), I conclude there was 

 no clearly defined spawning season. Nonovigerous 

 females with spermatophores attached occurred at 

 all months. There was no relation between ovari- 

 an stage and month of capture. 



Fecundity o( (our S. sculpta varied from 10,093 

 to 19,080 with a mean of 15,541. Eggs had a mean 

 diameter of 0.6 mm. 



All males were found to have spermatophores in 

 the vas deferens. Males with external sper- 

 matophores were present during all months ex- 

 cept January and July (Table 6). 



Sixty-eight percent of 114 S. sculpta stomachs 

 were empty. Stomachs of other individuals con- 

 tained sediment with Foraminifera (13%), fish 

 body parts ( 50^ ), polychaete parts (39f), crustacean 

 parts (5'r ), and unidentifiable gurry i6%). 



) EXTERNaL SPERMATOPHORES PRESENT 



lb. 



m 



r—^-H^rg-a^ 



^ 5 



^^l^^iT] 



XI 



J I , rrr:r> p^^ P^ ^ k£^ 



OVIGEROUS ^ 



FTTja 



.JE?L_ 



Fl« 



16 20 24 26 32 36 40 44 48 52 56 60 64 66 72 



SHORT CaRfiPACE LENGTH 1mm) 



;URE 7.— Length-frequency distribution of Sterenmastifi acultpa represented in catches included in this 



study. 



442 



