FISHERY BULLETIN: VOL. 83, NO. 1 



imodorsal rounded prominence and ending in 

 acute tip curved mesially. Distal projection of ven- 

 trolateral lobule, falling short of projection of dor- 

 solateral lobule, laminar, bifurcate laterally, and 

 thickened proximally forming plate bordered dis- 

 tally by transverse rib; latter supporting long 

 proximal salient of bifurcation; terminal part of 

 projection truncate and curved dorsally. 



Petasmal endopods joined in males as small as 3 

 mm cl, about 13 mm tl, but may be unjoined in 

 individuals with as much as 8.4 mm cl, about 21 

 mm tl. 



Appendix masculina as illustrated in Figure 

 55C. 



Thelycum (Fig. 56) with plate of sternite XIV 

 bearing pair of low protuberances bordered later- 

 ally (in adults) by narrow flanges, and separated 

 by moderately deep median depression. Median 

 plate of sternite XIII flask-shaped in outline, ta- 

 pering into long, slender spine reaching between 

 base and about midlength of basis of extended 

 second pereopod; plate set off from posterior com- 

 ponent by shallow incisions, flat or concave pos- 

 terolaterally, and with broad median depres- 

 sion (broader than areas and incisions flanking 

 it); posterior component of median plate flat or 

 slightly raised laterally, with posteromedian mar- 

 gin straight or convex. Paired short spines project- 

 ing anteroventrally from posterior margin of ster- 

 nite XI, spines broad basally, sharp and sometimes 

 produced in fine needle apically. Posterior thoracic 

 ridge narrow, with well-marked anteromedian 

 margin. 



The smallest impregnated females encountered 

 have a carapace of 5.3 mm, about 25 mm tl. 



Color. — Arana Espina and Mendez G. (1978) de- 

 scribed specimens from the waters of Peru as fol- 

 lows: Dorsum greenish gray, lighter-gray to pink 

 laterally Antennae red. Pereopods and pleopods 

 pink; merus of third maxilliped and pereopods 

 with red and yellow bands (toward distal end ac- 

 cording to their figure 15). Subdistal striking or- 

 namentation on lateral ramus of uropod consisting 

 of oval deep blue blotch bordered in yellow. In 

 contrast, Sosa Hernandes et al. (1980) found that 

 the specimens from southeast of Salina Cruz, 

 Golfo de Tehuantepec, Mexico, were cream with 

 orange hues. 



My observations, based on a large number of live 

 specimens taken off Panama Viejo, Panama, indi- 

 cate a color pattern much, but not exactly, like that 

 noted by Arana Espina and Mendez G. Dorsum 

 of carapace gray with broad transverse dark 



66 



Figure 56. — Sicyonia disdorsalis, 9 16 mm cl, off Punta 

 Calabazo, Panama. Thelycum. Scale = 2 mm. 



purplish band extending across epigastric tooth 

 and produced anteriorly in roughly pentagonal 

 spot reaching base of first rostral tooth. Bran- 

 chiostegite varying from dark purplish pink (in 

 most specimens) to milky white, sometimes with 

 grayish white longitudinal stripe along junction of 

 branchiostegite and dorsum. Abdomen gray with 

 middorsal carina banded: transverse dark gray 

 ones alternating with buff bands; large tooth pro- 

 jecting from carina on first somite purplish pink. 

 Anterior margin of pleuron of first three somites 

 bordered by white vertical stripe and posteroven- 

 tral areas of third and fourth somites also white. 

 Tergum of fifth somite bearing purplish pink 

 V-shaped (vertex anterior) marking posteriorly. 

 Telson and uropod gray with densely set yellow 

 chromatophores. Lateral ramus of uropod bearing 

 large garnet marking subdistally preceded by yel- 

 low patch, and contiguous to buff dot lying against 

 its mesial extremity. Antenna dark garnet. Third 

 maxilliped and pereopods pink, former with two 

 contiguous transverse bands, orange red one on 



