HAYNES: EARLY ZOEAL STAGES OF HIPPOLYTIDAE 



distal segment, two on proximal segment. No 

 outer seta on maxillule. 



Maxilla (Figure 6F). — Four long plumose setae 

 on scaphognathite; slightly longer, thicker seta at 

 proximal end; series of fine hairs along inner 

 margin; thinner series of hairs along outer 

 margin. Nine setae on unsegmented endopodite. 

 Basipodite and coxopodite bilobed. Basipodite 

 with five setae on each lobe. Coxopodite with 13 

 setae: 4 on distal lobe, 9 on proximal lobe. Most 

 setae on coxopodite setulose. 



First, second, and third maxillipeds. — Maxil- 

 lipeds similar to Stage I E. suckleyi; protopodite of 

 first maxilliped has 25-27 setae; setation formula 

 of endopodite of third maxilliped 5, 2, 1, 1, 4. 



Pereopods (Figure 6A). — All five pairs present, 

 poorly developed, unsegmented, and compacted 

 under cephalothorax. Pairs 1 and 2 biramous, 

 3-5 uniramous. 



Pleopods. — Absent. 



Abdomen and telson (Figure 6A, G). — Five 

 somites (somite six fused with telson). Fourth 

 and fifth somites with spine but no spinules on 

 posterolateral margins. Telson, shaped as in Stage 

 I E. suckleyi (Figure 3K), has 7+7 densely 

 plumose setae. Second and third pair of telsonic 

 setae are same length. Minute spinules along 

 terminal margin and at base of each seta except 

 possibly last setal pair. Enclosed uropods visible. 

 Anal spine present. 



Spirontocaris ochotensis — 

 Stage I Zoeae 



Stage I S. ochotensis similar to Stage I S. 

 arcuata. Spirontocaris ochotensis smaller than 

 S. arcuata and lacks rostrum; morphology of 

 carapace, antenna, mandibles, and maxilla slight- 

 ly different. Characters not mentioned are identi- 

 cal to Stage I S. arcuata. 



Mean total length of Stage I, 2.8 mm (range 

 2.7-2.9 mm, 10 specimens). Carapace of S. ocho- 

 tensis without rostrum. Pterygostomian spine and 

 usually a spine along anteroventral margin of 

 carapace (Figure 7A). Minute supraorbital spines 

 present. 



Antenna. — Plumose seta three times length of 



0. 5 mm 



0.25 mm 



Figure 7. — Stage I zoea of Spirontocaris ochotensis: A, cara- 

 pace and eyes, dorsal: B, antenna, ventral. 



terminal spine on tip of flagellum (Figure 7B). 



Mandible. — Narrow lacinia mobilis on left man- 

 dible (as in Stage I E. suckleyi, see Figure 3P). 



Maxilla. — Seven (rarely eight) plumose setae 

 on exopodite. 



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