FISHERY BULLETIN: VOL, 78, NO. 1 



and spines. Both the holotype and OSUBI 00181 

 have spinules on the inner side of the ocular 

 peduncle; OSUBI 00183 has no inner spinule but 

 has an outer spinule; USNM 171337 has no 

 spinules on the ocular peduncle. The number of 

 small spines on the rostrum varies from two to 

 seven with the smallest specimen having only two 

 spines. Paratypes USNM 171337 and OSUBI 

 00183 have very few spinules on the anterolateral 

 and first lateral spines compared with the other 

 two specimens. The number of spines on the inner 

 margin of the third maxilliped varies from two to 

 four. The specimens are similar in the ornamenta- 

 tion of the carapace and in their proportions ( Table 

 4). 



Munidopsis tuftsi belongs to a species complex 

 including M. crassa, M. aculeata, and M. sub- 

 squamosa. These species can be separated by ob- 

 serving several characteristics (Table 5). In this 

 complex, M. tuftsi most closely resembles M. 

 crassa, but differs in having a narrower anterior 

 carapace and narrower width between first lateral 

 spines compared with the posterior carapace 



width; anterolateral and first lateral spines of the 

 same size; and small spines on the lateral edges of 

 the rostrum. Although M. tuftsi has some charac- 

 teristics in common with M. aculeata and M. sub- 

 squamosa, it has a distinctly more spinous orna- 

 mentation on the carapace. A very small specimen 

 of M. tuftsi, OSUBI 01582, differs from the larger 

 specimens only in the smoother carapace or- 

 namentation and a larger ratio for anterior 

 carapace width/posterior carapace width (Table 

 5). The ratio of cornea diameter divided by eye- 

 spine length is quite variable for M. subsquqmosa, 

 but is usually between 0.46 and 0.55 for M. crassa 

 and M. tuftsi. 



Etymology. — Munidopsis tuftsi is named for Tufts' 

 Plain where all specimens were collected. 



Distribution. — The four specimens of M. tuftsi 

 were collected from Tufts Plain at depths of 

 3,500-3,858 m. Munidopsis crassa, the most simi- 

 lar species, has only been found from the Atlantic 

 Ocean (Laird et al. 1976). 



Table 4. — Morphometry of Munidopsis tuftsi. 



'Holotype. 



2 Rostrum broken at tip 



Munidopsis subsquamosa Henderson 1885 



Munidopsis subsquamosa Henderson 1885:414 

 (original description); Henderson 1888:152 (re- 

 description), pi. 16, fig. 4. 



Munidopsis subsquamosa Henderson var. pallida 

 Alcock 1894:331 (original description); Alcock 

 1901:268 (redescription). 



Munidopsis geyeri Pequegnat and Pequegnat 

 1970:149 (original description). 



Table 5. — Morphometric ratios and spina tion that distinguishes Munidopsis tuftsi, M. crassa, M. aculeata, and M. subsquamosa. 



Characteristics 



M. tuftsP 



M. crassa^ 



M. aculeata^ 



M. subsquamosa' 



'USNM 171336 (holotype), USNM 171337, OSUBI 00181, OSUBI 00183, OSUBI 01582. 



^USNM 9563 (holotype; measurements from Smith (1885) because holotype is in poor condition). USNM 19289. USNM 10803. 



^USNM 21277 



"USNM 21314 (holotype), USNM 171348, OSUBI 00185, OSUBI 00186. OSUBI 00187, M. geyer/— USNM 299042. TAMU 2-0574, TAMU 2-0575. 



^Unknown for holotype. 



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