PEREZ FARFANTE: ROCK SHRIMP GE^^JS SICYONIA 



Figure 16. — Sicyonia disparri,6 6 mm cl, Canal de San Lorenzo, Baja California Sur, Mexico. A , Petasma, dorsal view; B , ventral 

 view of same; C, right appendix masculina, dorsolateral view. Scale = 0.5 mm. 



carapace length as much as 4.9 mm (about 21 mm 

 tl). 



Appendix masculina as illustrated in Figure 

 16C. 



Thelycum (Fig. 17) with plate of sternite XIV, 

 produced in conspicuous anterolateral lobules, flat 

 except for deep, broad, median depression. Median 

 plate of sternite XIII narrow, lanceolate, tapering 

 gently into long, sharp spine reaching as far as 

 proximal 0.25 of basis of extended second 

 pereopods; plate constricted and deeply excavate 

 at level of coxae of fourth pereopods; posterior 

 component of plate with shallow, broad postero- 

 median emargination and well-marked transverse 

 suture. Paired conspicuous spines projecting an- 

 teromesially from posterior margin of sternite XI. 

 Posterior thoracic ridge with sharp, concave an- 

 teromedian margin but areas immediately lateral 

 to concavity flush with plate of sternite XIV. 



The smallest impregnated female encountered 

 has a carapace length of 5 mm, about 21 mm tl. 



Maximum size. — Males 6.9 mm cl, about 30 mm tl; 

 females 11 mm cl, about 44 mm tl. 



Figure 17. — Sicyonia disparri, holotype 5 10.4 mm cl, Bahia 

 San Luis Gonzaga, Baja California Norte, Mexico. 

 Thelycum. Scale = 1 mm. 



Geographic and bathymetric ranges. — In the Gulf 

 of California, from Bahia San Luis Gonzaga 

 (29°48'N, 114°22'W), Baja California Norte, and 



southward along the east coast of the peninsula, to 

 Isla Santa Magdalena (24°55'N, 112°15'W), Islas 

 Tres Marias, Nayarit, Mexico; also off Cabo San 



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