Excorallana tricornis tricomis 165 



Excorallana quadricornis (Hansen, 1890) 

 Figures 75C,D; 76A-C 



DIAGNOSIS S 13.2 mm, 9 12.1 mm. Eyes well separated. Cephalon in S 

 with two pairs of tubercles, anterior pair connected by low rounded ridge, 

 posterior pair situated mesial to eyes. Frontal lamina bell shaped, broadest 

 posteriorly. Pereonite 1 with submedian pair of low tubercles. Posterior mar- 

 gin of pereonite 7 and pleonites faintly tuberculate. Pleotelson with two sub- 

 median raised areas bearing short spines; lateral margins with incision; few 

 low tubercles basally. 



RECORDS Bermuda; St. Thomas, U.S. Virgin Islands; Jamaica, intertidal 

 in grassflats and between mangrove roots; Martinique; Belize; Venezuela. 



Excorallana sexticomis (Richardson, 1901) 

 Figures 75E,F; 76D-F 



DIAGNOSIS 6 7.9 mm, ovigerous 9 6.9-8.3 mm. Eyes well separated. Basal 

 antennular peduncular article in 6 with short anterodorsally directed tuber- 

 cle. Cephalon with two pairs of prominent tubercles, anterior pair shorter 

 than posterior pair, latter situated mesial to eyes. Frontal lamina, length less 

 than twice width, sides parallel to faintly converging anteriorly, apically 

 broadly rounded. Posterior margins of pleonites 2-5 with low rounded tuber- 

 cles, those near middorsal line largest. Pleotelson with two basal submedian 

 tubercles, numerous scattered dorsal spines, lateral margins with incision, 

 apex narrowly rounded. 



RECORDS Key West, Florida; Cuba; Puerto Rico; Twin Cays, Belize, shal- 

 low infratidal from dead mangrove wood. 



Excorallana tricornis tricornis (Hansen, 1890) 

 Figures 75G,H; 77 



DIAGNOSIS S 8.2 mm, 9 9.9 mm. Basal antennular article narrow, not 

 dilated. Cephalon in 6 with one median and two dorsal "horns." Eyes large, 

 well separated. Frontal lamina between two and three times longer than 

 basal width, sides subparallel, anteriorly rounded to subacute. Pereon 

 smooth. Margins of lateral incision of pleotelson separated by gap; anterior 

 margin of incision lined with short spines; scattered short spines on dorsum 

 of telson, but especially concentrated in two submedian patches. Uropodal 

 exopod, length 2.3-2.5 times width; apical notch nearly symmetrical. 



