FISHERY BULLETIN: VOL. 71, NO. 1 



three or four setae; coxa with one seta. The 

 rudimentary third maxilliped as in Figure 4H. 

 Chelipeds and pereiopods about twice as large 

 as in previous stage. 



ZOEA IV (Figure ID) 



Carapace length 1.94 mm (1.89-1.97); total 

 length 8.31 mm (7.62-8.95). There is an indi- 

 cation that the considerable range in total and 

 dorsal spine length is due to the nearness of a 

 particular animal to its next molt. In some in- 

 dividuals a relatively short, blunt dorsal spine 

 was observed; these individuals showed the 

 greatest total length, while on shorter individu- 

 als a relatively long, slender dorsal spine was 

 observed. Dorsal spine from 20 to 30% of the 

 total length, with small setae scattered along its 

 entire anterior edge; rostral spine usually as 

 long or longer than the dorsal spine. Lateral 

 spines flexed ventrally; carapace width, from tip 

 to tip of lateral spines, about one-third of the 

 total length of the body. A few additional setae 

 occur between the anterior edge of the dorsal 

 spine and the base of the rostral spine; 20 to 25 

 slender setae mid-ventrally to posteriorly on the 

 inner margin of the carapace. Abdomen with 

 six somites and the telson (Figure 51). The 

 blunt lateral spines on the second somite now 

 directed slightly posteriad; spines on other so- 

 mites more pronounced than in the previous 

 stage. The first somite bears four setae on the 

 middorsal surface; the second somite with two 

 setae anterior and four setae posterior to the 

 midline; the third somite with two setae mid- 

 dorsally and two on the posterodorsal margin; 

 somites 4 and 5 each with a pair of setae on the 

 posterodorsal margin, sixth somite naked; tel- 

 son as in previous stage but with the proximal 

 setae on the inner portion larger; pleopods and 

 uropods considerably enlarged from the previous 

 stage. Antennule (Figure 5A) with four aes- 

 thetes and two setae terminally, one group of six 

 aesthetes and another of two subterminally ; bud 

 of endopod enlarged from previous stage; basal 

 portion with five setae. Antenna (Figure 5B) 

 as in previous stage but with the endopodite con- 

 siderably enlarged and longer than the protop- 

 odite. Mandibular palp (Figure 5C) simple and 



much enlarged from the previous stage. The 

 endopodite of the maxillule (Figure 5D) the 

 same as in the previous stages; basal endite with 

 about 22 spinous setae, coxal endite with 17. 

 Scaphognathite of the maxilla (Figure 5E) with 

 about 54 marginal plumose setae; endopodite the 

 same as in the previous stages; distal lobe of the 

 basal endite with 12 spinous setae, proximal lobe 

 with nine; coxal endite as in the previous stage. 

 The exopodite of the first maxilliped (Figure 5F) 

 bears 17 setae; endopodite and basipodite as in 

 the previous stage; coxa with six setae. The 

 exopodite of the second maxilliped (Figure 5G) 

 with 19 setae; the terminal segment of the en- 

 dopodite with six setae, other segments as in the 

 previous stages; basipodite with three setae; 

 coxa with one. Exopodite of the third max- 

 illiped (Figure 5H) with slight articulation; 

 endopodite faintly five-segmented, the two distal 

 segments each with one spine. Chelipeds and 

 pereiopods considerably enlarged from previous 

 stage. 



MEGALOPA (Figures 6A and 7A) 



Carapace length 3.16 mm (3.02-3.26); total 

 length 6.46 mm (6.32-6.60). Rostrum one-fifth 

 the length of the carapace, strongly depressed 

 and bifid at the tip; a medial groove present from 

 interorbital position nearly to the distal end of 

 the rostrum. Eye stalks with a few small setae 

 on the anterior and dorsal surfaces. A carina 

 is present on each side of the mesogastric mid- 

 line (highest points on carapace) and another 

 prominence is present in the cardiac region of 

 the carapace; hepatic and branchial lobes round- 

 ed; setation sparse, occurring along the margins 

 of the rostrum, a few in the postorbital region, 

 and a few tufts on the mesogastric prominences; 

 numerous setae are present along the mid-ventral 

 to posterior margin of the carapace. Abdomen 

 with six somites and the telson; setation sparse 

 and as figured; pleopods with about 28 long 

 natatory setae each (Figure 7D); uropods with 

 about 15 each (Figure 7H). The peduncle of 

 the antennule (Figure 6B) is three-segmented, 

 the proximal segment with one plumose seta, the 

 middle segment with five setae subterminally, 

 and the distal segment has two setae; inner 



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