APRIETO: EARLY DEVELOPMENT OF FIVE CARANGID FISHES 



data derived from the study of larvae provide use- 

 ful tools in gaining insight into the abundance and 

 fluctuation of the size of spawning populations 

 (Farris, 1961 ). Patterns of larval development and 

 larval structures, when sufficient groups are 

 studied, are potential keys to possible relations 

 which often are not adequately illustrated in adult 

 morphology and osteology. The present paper 

 aims to contribute to the understanding of the 

 early life stages of members of the family Caran- 

 gidae. 



MATERIALS, METHODS, 

 AND TERMINOLOGY 



Larvae, juveniles, and adults were largely in 

 the collections of the Miami Laboratory, South- 

 east Fisheries Center. The larvae and juveniles 

 were collected with 1-m bongo plankton (Posgay, 

 Marak, and Hennemuth, 1968) and nekton nets on 

 board research vessels during oceanographic and 

 biological surveys and during the routine sam- 

 pling for larval fish in the Gulf Stream off Miami. 

 Descriptions of vessels, cruise tracks, and sam- 

 pling methods are available at the Miami 

 Laboratory, Southeast Fisheries Center. Some 

 specimens were contributed from a private collec- 

 tion and from the fish museum of the Center. One 

 species was raised in the marine fish larvae rear- 

 ing system of the Rosenstiel School of Marine and 

 Atmospheric Science, University of Miami. 



The larval development of the carangids in this 

 work is based on 551 larval and early juvenile 

 specimens ofDecapteruspunctatus, 94 ofElagatis 

 bipinnulata, 86 of Selene vomer, 64 of Seriola 

 zonata, and 31 of Oligoplites saurus. Meristic 

 characters and sequence of ossification data were 

 taken from stained and cleared specimens. The 

 complete sequence of ossification was not ob- 

 served, however, in Selene vomer and Oligoplites 

 saurus on account of the lack of transforming 

 specimens and poorly preserved materials, respec- 

 tively. 



The embryological and anatomical terms and 

 measurements used in this study follow largely 

 those of Lagler, Bardach, and Miller ( 1962), Man- 

 sueti and Hardy (1967), and Moser and Ahlstrom 

 (1970). Terms for ossification are those of Starks 

 (1911), Suzuki (1962), and Weitzman (1962). 

 Chromatophore terminology is from Fujii (1969). 

 However, for clarity, certain terms are defined as 



they relate to larvae of carangids. 



Growth stages beyond the yolk-sac stage are 

 defined according to Moser and Ahlstrom (1970), 

 and the terms prolarva and postlarva of Hubbs 

 (1943) are not used. The larval period lasts from 

 hatching to the attainment of juvenile characters. 

 The transformation or metamorphosis of the lar- 

 vae into juveniles is called the transitional period 

 and the individuals undergoing this process are 

 called transforming, metamorphic, or transitional 

 specimens. The fish is a juvenile when it has the 

 essential features of the adult, particularly the 

 complete fin ray counts. The juvenile period ter- 

 minates with the attainment of sexual maturity 

 when the fish is considered an adult. 



The dynamic approach of Moser and Ahlstrom 

 (1970) is adapted in the description of larval fish. 

 Here, a complete or fairly complete series of 

 growth stages from the smallest differentiated 

 larvae to the juvenile is assembled, and the de- 

 velopment of each character is traced sequen- 

 tially. The method used for determining apparent 

 relative abundance is based on Ahlstrom (1948). 



The youngest specimens collected in the plank- 

 ton were past the yolk-sac stage. While eggs were 

 present in the collections, identification is uncer- 

 tain in view of the conspicuous absence of the 

 intervening yolk-sac stages. Perhaps, the yolk sac 

 ruptured or collapsed at capture due to mechani- 

 cal stress. 



All specimens used in this study are deposited in 

 the larval fish laboratory of the Miami Labora- 

 tory, Southeast Fisheries Center of the National 

 Marine Fisheries Service. 



DESCRIPTIONS 



Rainbow runner, Elagatis bipinnulata 

 (Quoy and Gaimard) 

 Figure 1 



Literature 



Larval stages of this species from the 

 Indo-Pacific oceans were illustrated and described 

 by Okiyama (1970) who also traced their de- 

 velopment. Berry (1969) illustrated an 18.5-mm 

 juvenile from the Straits of Florida. Schnaken- 

 beck (1931) illustrated an 11.5-mm larva from the 

 Lesser Antilles under the name of Caranx hel- 

 volus. 



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