WILLIAMS AND BABA: SQUAT LOBSTERS FROM THE PACIFIC OCEAN 



anteriorly below line of rugae bordering lateral 

 suture to point behind anterior tip. 



Abdomen (Fig. 5a) unarmed but deeply sculp- 

 tured; transverse ridges of segments 2-4 lightly 

 rugose centrally but more strongly so laterally; 

 segments 5 and 6 punctate, lightly rugose later- 

 ally. Telson (Fig. 20 composed of 8 plates, 

 length-width ratio 0.85, midlateral plates 

 slightly convex on proximolateral margin. 



Eyes (Figs. 5a- 6) prominent; well exposed; 

 smoothly ovate cornea cupped within broad 

 based, fixed ocular peduncle bearing small an- 

 teromesial rugose patch but no spine; small, sub- 

 triangular plate posterolaterally adjacent to eye 

 and anterior to frontal margin. 



Basal article of antennular peduncle with dis- 

 tal margin irregularly crenulate; crest of slender 

 compound dorsolateral spines and stronger an- 

 terolateral spine flanked by inflated lateral sur- 

 face vdth in-egular, small spinules at periphery; 

 mesiodistal spine obsolescent. Antennal pe- 

 duncle with fixed basal article extended into fim- 

 briate distal margin, flat ventral spine, and 

 shorter crenulate lateral spine; succeeding arti- 

 cles short, second bearing stout compound 

 lateral angle and small, simple, distomesial 

 angle; third with acute mesiodorsal angle; fourth 

 with scalloped distal margin. 



Third maxilliped with ischium shorter than 

 meiTJS, bearing mesial crest armed with finely 

 uniform, evenly spaced corneous tipped spines, 

 an acute distodorsal angle, and subrectangular 

 distoventral angle flanked laterally by obso- 

 lescent spine. Basis with or 1 obsolescent spine 

 in line with crest on ischium. Merus (Fig. 5c) 

 with 3 strong spines on flexor margin; distal 

 margin irregular; extensor margin broadly 

 arched, bearirig 4 obsolescent spines and a more 

 prominent spine distally; ventral surface lightly 

 rugose. Carpus, propodus, and dactyl folded on 

 merus-ischium and about as long as those 2 arti- 

 cles together; dense setation on dorsal surface of 

 each, and distally on flexor surface of propodus 

 and dactyl. Sternite at base of third maxilliped 

 (Fig. 5f?) rather slender, anterior margin 

 bilobed, mesial lobe surmounted by small spine. 



Epipods present on coxae of pereopods 1-3. 

 Pereopods missing. 



Eggs few, large, principal axes measuring 1.3 

 X 1.9 mm. 



Remarks. — The distinctiveness of Munidopsis 

 grariosicorium leads us to describe it as a new 

 species even though it is represented by a single 

 imperfect specimen. This species seems close to 



M. follirostris Khodkina, 1973, from off the Pa- 

 cific coast of South America (30°13'9"S, 78°47'W, 

 1,280 m) in general features of the carapace, the 

 abdomen and telson, and in the relatively large 

 cornea; however, it differs in having the rostrum 

 triangular rather than markedly constricted 

 near the base, and the gastric region elevated in 

 anterior profile rather than evenly rounded (see 

 Khodkina 1973). 



More distantly, presence of epipods on the 

 chelipeds and first two ambulatory legs links the 

 species to M. rostrata (A. Milne Edwards, 1880) 

 and M. spinosa (A. Milne-Edwards, 1880), but 

 lack of any spine on the gastric region of the 

 carapace separates it from these 2 species. The 

 rostrum also differs from that of M. rostrata in 

 lacking distinct lateral teeth, and from that of M. 

 spiywsa in having some very small marginal 

 spines or tubercles (see Chace 1942). The short, 

 immovable, spineless eyestalks link the new 

 species to M. espinis Benedict, 1902, but it dif- 

 fers from that species in the deeper sculpturing 

 of the carapace and abdomen, and in the dense 

 scattering of small rugae but lack of spines on 

 the carapace, and in having the merus of the 

 third maxilliped armed with 3 rather than 2 

 spines on the flexor surface. There is only one 

 record of M. spinosa from the western Pacific, 

 and M. rostrata is represented by records from a 

 circumglobal band between lat. 40°N and 35°S 

 (see Baba 1988). 



Etymology. — The specific name is a noun in ap- 

 position from the Latin, "granosus", full of 

 grains, and "corium", leather, for the pebble- 

 grained surface of the carapace resembling 

 Scotch gi-ained leather. 



ACKNOWLEDGMENTS 



Contributors of specimens and crew members 

 of vessels who helped to make the collections are 

 owed a special debt of gratitude for securing the 

 rare material described here. Those persons and 

 donors are acknowledged individually in each of 

 the species accounts. KB thanks R. W. Ingle for 

 working space during a visit to the British 

 Museum (Natural History) in 1987, and R. B. 

 Manning for loaning specimens of M. crassa 

 from the USNM. The Mariana cruise was sup- 

 ported by gi-ant OCE83-11258 of the National 

 Science Foundation. Oregon State University 

 benthic collections were made with the financial 

 support of the Office of Naval Research (Con- 

 tract No. 000 14-67- A-0369-0009) and the U.S. 



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