HAYNES: PANDALIDAE, HIPPOLYTIDAE. ANDCRANGONIDAE LARVAE 



Figure 2. - Stage I zoeae of Lehbeus groenlandicus 

 showing slightly sinuous rostrum and posterolateral 

 spines on abdominal somites 4 and 5. 



2) and L. polaris, which have a sHghtly curved 

 rostrum (Haynes 1978b, 1981). In Stage I Hepta- 

 carpus camtschaticus, the rostrum is minute and 

 curves slightly dow^nward following the dorsal con- 

 tour of the eyes (Haynes 1981). 



In crangonid larvae, the rostrum is long, spini- 

 form, and without teeth in all larval stages except for 

 Stage I zoeae of Sclerocrangon zenkevitchi and S. 

 boreas, which lack a rostrum, and Stage I zoeae of 

 Paracrangon echinata, which have a spinulose 

 rostrum (Birshteyn* and Vinogradov 1953; Kurata 

 1964b; Makarov 1968). 



Spines on the Carapace 



The presence or absence of certain spines on the 

 carapace is useful for distinguishing between 

 families and identifying one or more stages. The lar- 

 val carapace (Fig. lA, C) may have supraorbital 

 spines (so), pterygostomian spines (pt), antennal 

 spines (as), and anteroventral denticles (ad). Supra- 

 orbital spines are absent in all larval stages of the 

 Crangonidae. For pandalid and hippolytid larvae, 

 supraorbital spines are usually absent in Stage I and 

 the megalopa, but present in the intermediate zoeal 

 stages. However, there are some exceptions to these 

 generalizations. Larvae oiPandalus hypsinotus have 

 supraorbital spines only in Stages II and III, and lar- 

 vae of P. kessleri have supraorbital spines only in 

 Stage II (Kurata 1955; Haynes 1976). Larvae of P. 



••Translator's spelling of "Birstein". 



prensor are without supraorbital spines in all larval 

 stages (Mikulich and Ivanov 1983). In the Hippolyt- 

 idae, Spirontocaris spinus, S. lilljeborgii, and prob- 

 ably S. phippsil have supraorbital spines in all larval 

 stages (the spines are minute in Stage I). Spirorir 

 tocaris ochotensis has minute supraorbital spines in 

 Stage I; whether supraorbital spines develop later is 

 unknown. Lebheus groenlandicus, a species with 

 abbreviated development, has supraorbital spines 

 only in Stage II and the megalopa (Stage III) Pike 

 and Williamson 1961; Haynes 1978b, 1981). In all 

 three families, pterygostomian spines are usually 

 present in all larval stages. Antennal spines are often 

 absent in Stage I but usually develop in later stages. 

 Anteroventral denticles are most prevalent in the 

 early stages and usually, but not always, disappear 

 during larval development. Branchiostegal and 

 hepatic spines are rarely, if ever, present in the lar- 

 val stages. 



Eyes 



Development of the eyes is the same for nearly all 

 members of the three families. The eyes are com- 

 pound and sessile in Stage I and are stalked in later 

 stages. The exception. Stage I Pandalopsis cocci- 

 nata, has compound eyes that are only partially 

 attached to the carapace (Kurata 1964a). 



Antennules 



In the Pandalidae and nearly all hippolytid and 



259 



