CHARACTERISTICS OF SOME LARVAL BOTHID FLATFISH, AND 

 DEVELOPMENT AND DISTRIBUTION OF LARVAL SPOTFIN FLOUNDER, 

 CYCLOPSETTA FIMBRIATA (BOTHIDAE)i 



BY ELMER J. GUTHERZ,^ FISHERY BIOLOGIST 

 ABSTRACT 



Pertinent literature on larval flatfish of the family 

 Bothidae and some of the characters helpful in identi- 

 fying these larvae are discussed. Helpful characters 

 are of two types; transitory, those which are lost, and 

 permanent, those which are retained. Transitory 

 characters include larvae pigmentation, elongate 

 dorsal and pelvic fin rays, and spina tion; permanent 

 characters include meristic counts, placement of 

 pelvic fin bases and fin rays, and caudal osteology. 



Developmental changes in general growth patterns, 

 formation of fins, larval spinatlon, pigmentation, 



migration of the right eye, and sequence of ossification 

 based on 171 larvae (1.7-14.5 mm. SL) collected oft the 

 south Atlantic coast of the United States is presented. 

 Several sizes of larvae showing spinatlon, pigmentation, 

 and elongate fin rays are illustrated, and one 

 illustration shows the degree of ossification. 



Spawning appears to occur between April and October 

 in waters of about 50 m. or less. Fertilized eggs have 

 not been seen, but their size at hatching is estimated 

 to be about 1.5 mm. 



Five families of flatfish occur off the south- 

 eastern coast of the United States (Bothidae, 

 Scophthalmidae, Pleuronectidae, Soleidae, and 

 Cynoglossidae). Species of bothids are common in 

 the inshore waters south of Cape Hatteras, N.C., 

 and are more numerous (13 genera and 49 species) 

 than are species of the other four families (Cyno- 

 glossidae, 1 genus and about 15 species; Soleidae, 

 3 genera and 5 species; Pleuronectidae, 1 genus 

 and 3 species; Scophthalmidae, 1 genus and 1 

 species) . 



The spotfin and other floundei-s discussed in this 

 paper are taken in industrial fish catches or are 

 caught incidentally in shrimping. Of these floim- 

 ders, only the fluke {Paralickthys) is removed from 

 the catch and its flesh utilized. Flukes are also 

 fished for sport or commercially along much of the 

 east and Gulf coasts of the United States. Several 

 other species of large flounders may be fished 

 commercially in the future if stocks of sufficient 

 size can be found. 



Larvae of flatfish along the southeastern coast 

 of the United States are jDoorly known; however, 

 a few authors have illustrated and described some 



1 Contribution No. 102, Bureau of Commercial Fisheries Biological Lab- 

 oratory, Brunswick, Ga. 31520. 



' Present address: Bureau of Commercial Fisheries Exploratory Fishing 

 and Gear Research Base, Pascagoula, Miss. 39567. 



Published May 1970. 



FISHERY BULLETIN: VOL. 68, NO. 2 



of these fish taken off North Carolina. Goode and 

 Bean (1896) identified an AncylapseUa diUcta 

 larvae (listed as Notosema dilecta, Bothidae) ; 

 Hildebrand and Cable (1930) had larvae of Para- 

 lickthys (Bothidae) ; and Deubler (1958) showed 

 the postlarvae of Paralickthys. Hildebrand and 

 Cable illustrated and described larvae of Sym- 

 pkwus plagiusa (Cynoglossidae) in 1930, and the 

 larvae of Trinectes maculatus (listed as Ackirus 

 fasciatus, Soleidae) in 1938 from off North 

 Carolina. 



I discuss the literature pertaining to the larvae 

 of Syacium (Bothidae) in some detail, because of 

 the many similar external features between the 

 larvae of Cyclopsetta and Syacium. Both genera 

 have many elongate dorsal and pelvic fin rays, a 

 single sphenotic spine, and heavy preopercular 

 spines, but larvae of Cyclofsetta have more num- 

 erous elongate dorsal fin rays, and the sphenotic 

 and preopercular spinatlon is smaller. 



This paper reports on development of larvae of 

 spotfin flounder, Cyclopsetta fimbnata, that U.S. 

 Fish and Wildlife Service vessels Theodore N. 

 GiU and Oregon collected off the south Atlantic 

 coast of the United States (fig. 1). It describes 

 growth changes in the head length, body depth, 

 eye diameter, snout length, and upper and lower 



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