FISHERY BULLETIN: VOL. 79. NO. 3 



to the laboratory and maintained as described 

 by Haynes (1980) for ovigerous Crangon francis- 

 corum angustimana. Most zoeae were released at 

 night, about 1 wk after the females were captured. 

 I do not know whether any of the larvae hatched 

 as prezoeae. 



For each species, 100 zoeae in groups of 10 zoeae 

 each were placed by large-bore pipette into 500 ml 

 beakers containing about 400 ml of filtered sea- 

 water. Seawater in the beakers was changed every 

 other day. Newly hatched nauplii of brine shrimp, 

 Artemia salina, from San Francisco Bay were 

 offered, but none were eaten by the zoeae. The 

 zoeae of each species were preserved in b% For- 

 malin^ about 10 d after their release. Some of the 

 zoeae of L. polar is , E. suckleyi, and E.fabricii had 

 molted to Stage II. 



To study segmentation and setation, I cleared 

 some zoeae in 10% KOH and stained the exo- 

 skeleton with Turtox CMC-S (acid fuchsin stain 

 mountant). Because the paired appendages of the 

 zoeae are symmetrical, only the left members are 

 figured. The mandibles, an exception, are drawn 

 as pairs. For clarity in the illustrations, setules on 

 setae are usually omitted, but spinulose setae are 

 shown. Illustrations are partly schematic and 

 represent typical setal counts. Any variation in 

 setal counts is noted in the text. 



DESCRIPTION OF ZOEAE 



Terms used in the text, nomenclature of gills 

 and appendages, and techniques of measurement 

 and illustration are those given by Haynes (1976). 

 Carapace length refers to the straight-line dis- 

 tance from posterior margin of the orbit to mid- 

 dorsal posterior margin of the carapace. Total 

 body length refers to the distance from the tip of 



^Reference to trade names does not imply endorsement by 

 National Marine Fisheries Service, NOAA. 



the rostrum to the posterior margin of the telson, 

 not including telsonic spines. Stage I zoeae of S. 

 ochotensis lack a rostrum; therefore, for this 

 species only, total body length refers to the dis- 

 tance from anterior middorsal margin of the 

 carapace to posterior margin of the telson. Tel- 

 sonic setae or spines are numbered from an inner 

 (medial) to outer (lateral) direction. The setation 

 formulas proceed from the distal to the proximal 

 ends of appendages. Principal morphological char- 

 acteristics used to separate the species of zoeae 

 described in this report are summarized in Table 1. 



Lebbeus polaris — Stage I Zoeae 



Mean total length of Stage I (Figure lA), 5.4 mm 

 (range 5.2-5.6 mm, 3 specimens). Rostrum slightly 

 sinuate, without teeth, about one-half length of 

 carapace. Carapace with a rounded prominence at 

 base of rostrum and near posterior margin. Ven- 

 tral margin of carapace smooth except for ptery- 

 gostomian spine. No supraorbital spines. 



Antennule (Figure IB). — First antenna, or an- 

 tennule, an unsegmented peduncle with conical 

 projection and heavily plumose seta. Conical pro- 

 jection with four aesthetascs of various lengths. 



Antenna (Figure IC). — An inner flagellum (en- 

 dopodite) and outer scale (exopodite). Flagellum 

 two-segmented, slightly longer than scale; distal 

 segment styliform, with terminal plumose seta 

 and short spine. Proximal segment of flagellum 

 has simple seta near joint. Scale distally divided 

 into four joints, fringed with 11 heavily plumose 

 setae. Protopodite with two simple spines: one at 

 base of flagellum, other at base of scale. 



Mandibles (Figure ID). — Well developed, with- 

 out palps. Four teeth on incisor process of left 

 mandible in contrast to diserrate incisor process 



Table l. — Principal morphological characteristics of hippolytid zoeae described in this report. 



'Small lobe in Stage I and II; absent in later stages, 



^Poorly developed in Stage I and II; pereopods gradually develop in later stages. 



^Undeveloped pereopods. 



"Poorly developed in Stage I; pereopods gradually develop in later stages. 



422 



