FISHERY BULLETIN: VOL. 83. NO. 3 



1 , mm 



Figure ll.-Pereopod 4 or 5 of Sclerocrangan 

 larva with characteristic sickle-shaped daot\'l. 



Larvae not free living but cling to pleopods of 

 female. In all described stages, carapace without 

 anteroventral denticles; flagellum of antennule 

 segmented; basal portion of antennule shaped as in 

 adult; maxillipeds with undeveloped exopodites; exo- 

 y)odites with a few feeble natatory setae; pereopods 

 segmented, without exopodites. In Stage I, rostrum 

 absent; carapace covers sessile eyes; telson and abdo- 

 minal somite 6 jointed. In Stage II, rostrum short, 

 triangular, flattened dorsoventrally. Length: Stage 

 I, 9.0 mm; Stage II, 11.5 mm. Range: Sea of Japan 

 to Chukchi Sea to Bare Island, WA; arctic Canada to 

 Cape Cod, MA; North Atlantic Ocean and arctic 

 Europe; Spitsbergen to Faroe Islands; depth, 0-366 

 m (Butler 1980). 



Sclerocrangon salebrosa (Owen) 



One larval stage. 



Stage I, from plankton; figure 27 in Makarov 

 (1967). 



Embryos, from female; Stage I and Stage II ("post- 

 larval"), from plankton; figures 1 and 2 in 



Makarov (1968). Larvae from plankton identi- 

 fied by comparison with embryos dissected from 

 eggs. 



Larvae free living. In Stage I, rostrum spiniform; 

 carapace with anteroventral denticles; exopodites of 

 maxillipeds fully developed, each exopodite with 5 

 natatory setae; telson exceptionally wide with 22 -t- 

 22 setae. Length: Stage I, 10.3-10.5 mm. Range: 

 Okhotsk Sea; Hokkaido; no depth range (Kurata 

 1964b; Makarov 1967). 



Sclerocrangon zenkevitch't Birstein and Vinogradov 



Only Stage I described, known parentage; figure 5 

 in Birshteyn and Vinogradov (1953). 



Carapace nearly circular laterally, without ros- 

 trum; cephalothorax and abdomen without spines or 

 denticles; telson ovoid. Length: Stage I, 7.2 mm. 

 Range: Bering Sea; depth, 2,995-3,940 m (Birshteyn 

 and Vinogradov 1953). 



BIOLOGY 



Although pandalid, hippolytid, and crangonid lar- 

 vae are common inhabitants of the neritic mero 

 plankton of temperate and arctic waters of the North 

 Pacific Ocean, only a few studies on their biology 

 have been published. The most complete studies are 

 those of Haynes(1983), Makarov (1967), and Rothlis- 

 berg (1975). Haynes described the relative abun- 

 dance and distribution of pandalid shrimp larvae in 

 the lower Cook Inlet-Kachemak Bay area, Alaska; 

 Makarov (1967) described the distribution of decapod 

 shrimp larvae of the West Kamchatkan shelf; and 

 Rothlisberg (1975) discussed larval ecology oiPan- 

 dalus jordani off the Oregon coast. In this section, I 

 review the findings of these authors and supplement 

 their findings with information from the literature. 

 To avoid redundancy of citation, only information in 

 addition to that given by Haynes, Makarov, and 

 Rothlisberg is cited by author and date. This section 

 does not include every known facet of the biolog>' of 

 decapod shrimp larvae of the northern North Pacific 

 Ocean; however, more information can be acquired 

 from the papers of Haynes, Makarov, and Rothlis- 

 berg and from their bibliographies. 



Areas of high abundance of Stage I larvae ap- 

 parently indicate areas where females are releasing 

 larvae. For example, in Kachemak Bay in 1972, 

 Stage I larvae of Pandalus borealis, P. goniunts, P. 

 hypsinotixs, and Pandaiopsis dispar were most abun- 

 dant in plankton samples collected in the same area 



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