Abstract.- Egg and larval devel- 

 opment of California halibut Para- 

 lichthys californicus and fantail sole 

 Xystreurys liolepis are described 

 from specimens collected in the near- 

 shore zone of the Southern Califor- 

 nia Bight (except early-stage eggs, 

 described from reared material). 

 Eggs of both species have spherical 

 unornamented chorions, homogenous 

 yolk, and a single oil globule. Chorion 

 diameters of P. californicus and X 

 liolepis eggs are 0.64-0.83 mm and 

 0.72-0. 90mm, respectively. Respec- 

 tive oil globule diameters are 0.09- 

 0.16mm and 0.14-0.24 mm. Initial 

 embryonic pigmentation patterns are 

 similar; however, distinctive pigment 

 patches develop in the dorsal and 

 ventral finfolds and at the tail tip on 

 late-stage X. liolepis embryos. Lar- 

 vae of P. californicus can be distin- 

 guished from those of X. liolepis at 

 all stages of development. Internal 

 notochord pigment is easily observed 

 in P. californicus but is not visible in 

 X liolepis ; sphenotic spines are pres- 

 ent in P. californicus but absent in 

 X liolepis. Body shape, robust in 

 X liolepis and laterally compressed 

 in P. californicus, and external pig- 

 mentation, heavier in X liolepis, 

 separates flexion and postflexion 

 specimens. 



Development of Eggs and 

 Larvae of California Halibut 

 Paralichthys californicus and 

 Fantail Sole Xystreurys liolepis 

 (Pisces: Paralichthyidae) 



Debra Oda 



Section of Fishes. Natural History Museum of Los Angeles County 

 900 Exposition Boulevard. Los Angeles, California 90007 



Manuscript accepted 28 January 1991. 

 Fishery Bulletin, U.S. 89:387-402 (1991). 



The California halibut Paralichthys 

 californicus (Ayres) is an important 

 sport and commercial fish, ranging 

 from the Quillayute River, Washing- 

 ton (Miller and Lea 1972, Eschmeyer 

 et al. 1983), to Almejas Bay, Baja 

 California (LACM 38108-8). In the 

 southern California portion of the 

 range, the eggs and larvae of P. cali- 

 fornicus are relatively abundant 

 within the nearshore zone (Gruber et 

 al. 1982, Barnett et al. 1984, Laven- 

 berg et al. 1986). However, similar- 

 ities between the eggs and larvae of 

 P. californicus and the fantail sole 

 Xystreurys liolepis Jordan and Gil- 

 bert may have caused previous iden- 

 tifications of these two species to be 

 confused (Lavenberg et al. 1986), 

 particularly within the geographical 

 overlap of their ranges (X liolepis 

 ranges from Monterey Bay, Califor- 

 nia to the Gulf of California; Miller 

 and Lea 1972, Eschmeyer et al. 

 1983). Early-life-history information 

 has been published for both species, 

 but it has not been adequate to 

 separate them at all stages. Ahlstrom 

 and Moser (1975) illustrated a series 

 of four P. californicus larvae, but the 

 two smallest specimens (2.5 and 3.8 

 mm) do not fit pigmentation char- 

 acters that I will present for P. cali- 

 fornicus. Ahlstrom et al. (1984) illus- 

 trated a postflexion larva of each spe- 

 cies and included information on the 

 eggs (chorion and oil globule size, 

 chorion and yolk texture) of P. cali- 



fornicus and the larvae of both spe- 

 cies (number of elongate dorsal fin 

 rays and sizes at hatching, flexion, 

 and transformation). Eggs of P. cali- 

 fornicus were erroneously reported 

 as demersal rather than pelagic in 

 Frey (1971). 



My purpose is to provide descrip- 

 tions of the eggs and larvae of Para- 

 lichthys californicus and Xystreurys 

 liolepis and to give characters to sep- 

 arate them from each other and from 

 other commonly occurring fish eggs 

 and larvae in the coastal waters of 

 southern California. 



Materials 

 and methods 



The main source of material for this 

 study was provided by the Bightwide 

 Ichthyoplankton Program at the Nat- 

 ural History Museum of Los Angeles 

 County (LACM). Beginning in 1978, 

 ichthyoplankton sampling within the 

 Southern California Bight was car- 

 ried out in nearshore waters (at 

 depths ranging from 8 to 36 m, ex- 

 tended to 75 m in 1981). Samples 

 were collected in discreet depth and 

 oblique tows using manta, bongo, and 

 auriga frames equipped with nets of 

 333 /i or 1/8-inch stretch mesh (Brew- 

 er and Smith 1982, Love et al. 1984, 

 Lavenberg et al. 1986). Plankton 

 samples were fixed in standard 5% 

 buffered formalin on board ship. 

 Most of the samples were maintained 



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