PfeREZ FARFANTE: ROCK SHRIMP GENUS SICYONIA 



Figure 43.—Sicyonia martini Perez Farfante and Boothe (1981), paratypec? 19 mm cl, off Puerto Escondido, Golfo de Panama. 



Lateral view. Scale = 5 mm. 



Description. — Body relatively slender (Fig. 43). 

 Carapace with sparse long setae intermingled 

 with elongate patches of shorter ones situated on 

 dorsum, ventral to hepatic sulcus, posterior to 

 pterygostomian region, and on posterodorsal part 

 of branchiostegite; patches also present on abdom- 

 inal terga. Abdomen tuberculate, tubercles 

 numerous on first five somites, few on sixth. 



Rostrum comparatively long, conspicuously 

 surpassing eye, reaching as far as distal 0.33 of 

 second antennular article, its length, 0.40-0.54 cl, 

 increasing linearly with carapace length (Fig. 44); 

 armed with two or three dorsal teeth and cluster of 

 apical teeth, both groups varying in disposition 

 and number in males and females. In males, ros- 

 trum horizontal or directed upward at slight angle 

 of no more than 10°, but weakly decurved at tip, 

 with three dorsal teeth evenly spaced; first rostral 

 tooth situated immediately anterior to orbital 

 margin, last usually separated from upper apical 

 tooth by interval (about 0.33 rl) slightly greater 

 than that between dorsal teeth; apical cluster con- 

 sisting of three or four teeth (76% and 24% , respec- 

 tively), with subterminal ventral tooth situated 

 not far from adjacent apical tooth. In females, ros- 

 trum strongly elevated at angle of 40°-50°, its ven- 

 tral margin straight or, more often, strongly con- 

 vex along midlength, and with two dorsal teeth; 

 first rostral tooth placed distinctly anterior to orbi- 



10 



E 

 E 



6 • 



c 

 _« 



E 



3 4 



10 15 20 



carapace length (mm) 



25 



Figure 44. — Sicyonia martini. Relationship between rostrum 

 length and carapace length (regression equation, j = 0.76705 + 

 0.39436X). 



tal margin; interval between second tooth and 

 upper apical tooth slightly shorter than that be- 

 tween first and second; apical cluster consisting of 

 three, four, or five teeth (1, 87, and 12%, respec- 

 tively), ventral one subterminal, distinctly re- 

 moved from adjacent apical tooth; teeth of apical 



53 



