PERKINS: LARVAL STAGES OF DEEP SEA RED CRAB 



five-segrmented with 2, 2, 1, 2, 5 setae on the seg- 

 ments (proximally to distally) ; basipodite with 

 10 setae, coxa with 1 seta. The exopodite of the 

 second maxilliped (Figure 2G) bears four, one- 

 jointed natatory setae terminally; endopodite 

 three-segmented with 1, 1, 5 setae; basipodite 

 with four setae; coxa naked. 



ZOEA II (Figure IB) 



Carapace length 1.07 mm (1.00-1.13), total 

 length 4.97 mm (4.89-5.02) . Spines on carapace 

 as in Zoea I. The rostral spine is nearly as long 

 as the dorsal spine. Width of carapace from tip 

 to tip of lateral spines about four-tenths the total 

 length of the body. A short, slender seta is 

 present at each side of the posterior margin 

 of the dorsal spine's base. One to four small 

 setae are scattered along the anterior edge of 

 the proximal half of the dorsal spine; a small 

 seta is present slightly above and in line with 

 i the base of each eye. Eyes stalked. Postero- 

 ventral edge of carapace finely serrate with three 

 of four short, slender setae on the inner margin. 

 . Abdomen with five free somites (sixth fused with 

 ! telson) (Figure 3H). Spination and setation 

 as in Zoea I except an additional pair of short 

 setae has been added proximally on the inner 

 margin of the telson. The spines on the abdomen 

 are somewhat more pronounced than in Zoea I. 

 Theantennule (Figure 3A) bears four aesthetes, 

 plus one short and one long setae terminally. 

 Protopodite of the antenna (Figure 3B) as in 

 Zoea I; the exopodite terminates in two unequal 

 setae and the endopodite is evident as a bud. 

 Mandible as in Figure 3C. Endopodite of the 

 maxillule (Figure 3D) as in Zoea I; a single, 

 long plumose seta is present on the protopodite; 

 basal endite with 12 spinous setae, coxal endite 

 with 11. The scaphognathite of the maxilla 

 (Figure 3E) bears 22 marginal plumose setae; 

 endopodite bilobed with five setae on the distal 

 lobe, three on the proximal ; basal endite with 

 seven setae on the distal lobe, five on proximal; 

 coxal endite with four setae on each lobe. The 

 two-segmented exopodite of the first maxilliped 

 (Figure 3F) now bears 10 or 11 articulated 

 natatory setae terminally; endopodite, basipo- 

 dite, and coxa as in Zoea I. The exopodite of 



the second maxilliped (Figure 3G) bears 11 ar- 

 ticulated natatory setae; endopodite, basipodite, 

 and coxa as in Zoea I. The third maxillipeds, 

 chelipeds, and pereiopods are evident as minute 

 buds. 



ZOEA III (Figure IC) 



Carapace length 1.42 mm (1.35-1.48) ; total 

 length 6.13 mm (5.75-6.48). The lateral spines 

 are more ventrally flexed and the number of 

 small setae on the anterior edge of the dorsal 

 spine has increased from the previous stage. 

 There are 15 small setae along the inner margin 

 of each side of the posteroventral and posterior 

 edge of the carapace. Abdomen with six somites 

 and the telson (Figure 41). The spination and 

 setation of somites two through five is the same 

 as in the previous stage. The first somite now 

 bears two small setae on the middorsal surface; 

 sixth segment naked. Telson with five pairs of 

 setae on the inner portion. The pleopods are 

 evident as buds on somites 2 through 5; uropods 

 as buds on the sixth. Antennule (Figure 4A) 

 with four aesthetes and three setae terminally, 

 plus three aesthetes subterminally; basal portion 

 swollen and the endopod occurs as a small bud. 

 The protopodite and exopodite of the antenna 

 (Figure 4B) as in the previous stage; the en- 

 dopodite is now about the same length as the 

 exopodite. The mandible (Figure 4C) now bears 

 a simple palp, evident as a bud. The endopodite 

 of the maxillule (Figure 4D) has five or six long 

 plumose setae on the distal segments; the basal 

 and coxal endites each bear about 17 spinous 

 setae. The scaphognathite of the maxilla (Fig- 

 ure 4E) bears about 31 marginal plumose setae; 

 endopodite and basal endite as in previous stage; 

 coxal endite with five spinous setae on distal lobe, 

 and nine on the proximal lobe. The exopodite 

 of the first maxilliped (Figure 4F) bears about 

 14 articulated natatory setae terminally; the 

 distal segment of the endopodite now bears six 

 setae; setation of other segments as in the pre- 

 vious stages, as is that of the basipodite; coxa 

 with three setae. The exopodite of the second 

 maxilliped (Figure 40) bears about 14 articu- 

 lated natatory setae; setation of endopodital seg- 

 ments as in the previous stages; basipodite with 



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