FISHERY BULLETIN: VOL. 75, NO. 2 



spine brilliant red, and prosartema pink; flagella 

 red proximally fading to pink distally. Antenna 

 pink. Third maxilliped and pereopods with coxa 

 and basis white, remaining podomeres reddish. 

 Pleopods with basis white but bearing pink 

 semicircular, lateral patch; exopods white proxi- 

 mally, with red and pink transverse bands on 

 midportion, and white distal patch; endopods 

 white with pink band at midlength. Eye with 

 peduncle white, and separated from cornea by 

 two lines, proximal pink and distal red; basal 

 article pink. 



Salmon phase: Carapace anterior to cervical 

 sulcus deep salmon, cardiac region, and ground 

 color of abdomen pale salmon; rostrum (except 

 for white tip) and branchiostegite bright reddish 

 orange, that on branchiostegite sharply delimited 

 dorsally along hepatic sulcus and branchiocardiac 

 carina; apices of rostral teeth and spines, as well 

 as postrostral and cervical carinae deep orange- 

 red; bases of teeth and spines, and cervical sulcus 

 opaque white. Tergum of first through fifth ab- 

 dominal somites with posterior, transverse band 

 of reddish orange, band broad on middorsal por- 

 tion, tapering ventrally to base of pleuron, from 

 there extending along posterior margin and onto 

 ventral margin; middorsal carina as well as pos- 

 terior and ventrolateral margins of sixth somite 

 deep reddish orange. Telson with ground color 

 deep salmon, except for yellowish white basal 

 portion; lateral portion of margins and paired 

 carinae bright orange-red, giving rise on each 

 side to angle with vertex on spine. Pereopods 

 with coxa and basis white, and remaining podo- 

 meres salmon with longitudinal orange-red strip. 

 Pleopods yellowish, but basis with roughly semi- 

 circular lateral white patch subtended by bright 

 reddish orange stripe on lateral margin. Uropod 

 mostly salmon; lateral ramus with distalmost 

 portion bright red and mesial ramus with tip 

 white. 



Opaque white phase: Ground color opaque 

 white with very pale salmon suffusion, more 

 intense on rostrum; however, tip of rostrum, teeth 

 and adrostral carina corneous; cardiac region 

 grayish white, and entire branchiostegite milky 

 white; branchiostegal and hepatic spines as well 

 as cervical and postrostral carinae orange-red; 

 longitudinal streak of orange-red extending 

 posteriorly from dorsal end of cervical carina 

 well beyond midlength of carapace. Pleura of first 

 five abdominal somites with milky white U- 

 shaped band following contour of margin; mid- 



dorsal carina and posterior and ventrolateral 

 margins of sixth somite orange-red. Telson almost 

 white with median sulcus orange-red. Lateral 

 ramus of uropod with oblique, milky white stripe 

 at base of distal fourth, and subtended distally 

 by intense salmon colored band and this, in turn, 

 by white tip; mesial ramus with large, proximo- 

 mesial, suboval, milky white patch bounded 

 laterally by salmon band, and with distalmost 

 portion milky white. Antennular peduncle deep 

 salmon proximally, becoming pink distally; 

 prosartema, antennular flagella, and antenna 

 pink. Third maxilliped and pereopods with coxa 

 and basis white, and remaining podomeres white 

 with very light pink suffusion. Pleopods pinkish 

 white bearing milky white, semicircular, lateral 

 patch. Ocular peduncle white, and bearing 

 orange-red stripe along border with cornea. 



Maximum size.-The largest male examined by me 

 has a carapace length of 42 mm, about 173 mm tl, 

 and the largest female, 61.5 mm cl, about 219 mm 

 tl; however, Klima (1969), in his work on length- 

 weight relation, recorded larger specimens of both 

 sexes, a male within the range of 180-184 mm tl 

 and a female within 225-229 mm tl. 



The sizes at which maturation occurs were de- 

 termined by Anderson and Lindner ( 1971) to be at 

 about 125 mm tl in males and about 155 mm tl 

 in females. 



Geographic and bathymetric ranges. -Pleoticus 

 robustus ranges (Figure 34) from immediately 

 south of Martha's Vineyard, Mass. (40°00'15"N, 

 70°54'00"W), through the Gulf of Mexico, and the 

 Caribbean to French Guiana (07°05'N, 52°47'W), 

 occurring on the upper continental slope at depths 

 between about 180 and 730 m (Figure 9). It has 

 been found only occasionally north of Cape Hat- 

 teras, and seems to be scarce off the Guianas. 

 Inasmuch as this species has not been reported 

 from Brazilian waters, French Guiana is cited 

 here as the southernmost limit of the species on 

 the basis of samples taken during the Oregon 

 cruises off northeastern South America. The 

 southern range of the species given by Bullis and 

 Cummins (1963) was based on the same collec- 

 tions; consequently their statement that the royal 

 red reaches Brazil should be understood to mean 

 that it extends to about the border between 

 French Guiana and Brazil. 



The highest concentrations of P. robustus — off 

 the northeast coast of Florida and in the north- 



304 



