11(10) Cannula of pleopod 2 completely enclosed between two promin- 

 ent, heavily sclerotized, non-dentate, broadly rounded 

 'ventral' and 'dorsal' processes (Fig. 30E, F) ; distal end 

 of endopod with small degree of torsion so that 'ventral' 

 groove lies laterally; endopod shape and proportions of 

 segments as in Fig. 30D. Endopod of uropod distinctly 

 longer than peduncle (Fig. 30G, H) : A. nodulus 

 Cannula of pleopod 2 not enclosed between two processes as des- 

 cribed above (i.e. not as indicated in Fig. 30E, F) ; dis- 

 tal end of endopod not displaying any obvious sign of 

 torsion; ventral groove distinct; endopod shape and pro- 

 portions of segments more or less dissimilar to drawing 

 of Fig. 30D. Endopod of uropod typically only slightly 

 longer than or subequal in length to peduncle 12 



12(11) Cannula of pleopod 2 visible from ventral view, lateral pro- 

 cess not (or only slightly) developed, mesial process prom- 

 inent and bifid, caudal process wide and irregularly dentate 

 (Fig. 31D, E) ; endopod shape and proportions of segments 

 as in Fig. 3 IC: A. dentadactylus 

 Cannula of pleopod 2 often hidden by lateral process in ventral 

 view, lateral process well-developed, mesial process prom- 

 inent but with either rounded or dentate distal margin (not 

 bifid) , caudal process absent or rounded (not dentate) ; 

 endopod shape and proportions of segments more or less dis- 

 similar to Fig. 31C 13 



13(12) Caudal process of pleopod 2 absent, distal dorsal surface of 

 endopod with numerous minute setae, lateral process non- 

 sclerotized with rounded margin, mesial process obtusely 

 dentate (Fig. 32C, D) ; endopod shape and proportions of 

 segments with some variation but typically as shown in 

 Figs 32B, 33A-G. Uropods about half as long as telson 

 (always < 0.7) , peduncle about as wide as long (Fig. 32E) : 



A. hvevicauda hvevioauda 

 [Pending a further examination of specimens, two subspecies 

 of A. hvevioauda have tentatively been proposed by Williams 

 (1970), A, hvevioauda hvevioauda Forbes, 1876, and A. hvevi- 

 oauda hivittatus Walker, 1961. The differences between them 

 are small and mainly involve slight differences in setation, 

 segment proportions, and number of segments in antennal fla- 

 gella. Table 3 details the principal differences.] 

 Distal endopodial processes of pleopod 2 (considered as a 

 whole) of shape and arrangement other than as described 

 for A. hvevioauda hvevioauda, distal dorsal surface of 

 endopod lacks minute setae; endopod shape and proportions 

 of segments more or less dissimilar to drawings of Figs 

 32B, 33A-G. Uropods subequal to or slightly longer than 

 telson, peduncle always longer than wide 14 



37 



