FISHERY BULLETIN: VOL. 83, NO. 1 



Figure 8. — Sicyonia laevigata, 9 9 mm cl, Punta Paitilla, Panama. Lateral view. Scale = 5 mm. 



antennular peduncle, its length (0.40-0.77 cl) in- 

 creasing linearly with carapace length (Fig. 9); 

 relatively deep, usually with dorsal and ventral 

 margins straight and subparallel; subhorizontal 

 or upturned to as much as 35°; armed with two 

 (25%), three (72%), or four (3%) dorsal teeth and 

 two (5%), three (33%), or four (62%) apical teeth, 

 additional rudimentary one present between two 

 ventral ones; ventralmost tooth, largest of apical 

 cluster, subterminal, directed anteriorly or curved 

 upward, and distinctly removed from adjacent one. 

 Position of first dorsal tooth ranging between 0.09 

 and 0.30 (mean 0.18) rl from level of orbital mar- 

 gin, and that of second tooth between 0.42 and 0.60 

 (mean 0.45) rl; third tooth, when present, between 

 0.76 rl and tip of rostrum (mean 0.87); and fourth, 

 rarely present, located at tip. Two, occasionally 

 one or three, minute but rather heavy movable 

 spinules (often absent in adults) flanking ventral 

 margin of rostrum, just posterior to apical teeth. 

 Adrostral carina, subparallel to ventral margin of 

 rostrum, extending to base of apical cluster. 



Carapace with postrostral carina, barely dis- 

 tinct between teeth, bearing three unequal, 

 acutely produced teeth: 1) epigastric tooth, 

 situated between 0.06 and 0.16 (mean 0.12) cl from 

 orbital margin, subequal to or only slightly larger 

 than first rostral and conspicuously smaller than 

 more posterior teeth; 2) middle tooth, placed be- 

 tween 0.35 and 0.50 (mean 0.45) cl from orbital 

 margin; and 3) posterior tooth positioned be- 

 tween 0.68 and 0.80 (mean 0.72) cl from orbital 

 margin, well in advance of posterior margin of 

 carapace. Antennal spine absent or barely per- 

 ceptible, antennal angle 90° to broadly obtuse, 

 lacking buttress; hepatic spine long, sharply 

 pointed, projecting from low buttress, and situated 



* 4 



6 9 



carapace length (mm) 



12 



15 



Figure 9. — Sicyonia laevigata. Relationship between rostrum 

 length and carapace length (regression equation, >> = -0.39153 

 + 0.64127X). 



between 0.22 and 0.30 (mean 0.25) cl posterior to 

 orbital margin. Postocular sulcus short; hepatic 

 sulcus shallow, subhorizontal; hepatic carina lack- 

 ing; branchiocardiac carina barely evident. 



Ocular calathus broad and bearing conspicuous 

 tuft of setae on dorsolateral extremity; ratio of 

 length of lateral margin to width (across base of 

 cornea) 0.54-0.65 (mean 0.60) and ratio length of 

 lateral margin to cl 0.11-0.15 (mean 0.13). 



Antennular peduncle with stylocerite produced 

 in acute spine reaching 0.65-0.75 of distance be- 

 tween lateral base of first antennular article and 

 mesial base of distolateral spine; latter extending 

 only to about proximal 0.40 of second antennular 

 article. Antennular flagella short, mesial one, 

 about 0.7 as long as lateral; latter, about 0.4 cl. 



Scaphocerite almost reaching or slightly sur- 



12 



