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INTRODUCTION
The genus Elops (Elopidae) is distributed worldwide in tropical and subtropical marine and brackish waters (Eschmeyer & Fong, 2011) and includes seven species. Until recently, only ladyfish had been described for the western Atlantic, Elops saurus (Linnaeus, 1766) (Gehringer, 1959; Figuereido & Menezes, 1978). Some authors recognized two morphs of Elops in that area (Smith, 1989; McBride & Horodysky, 2004). Smith (1989) recognized Elops saurus larvae as a high-count morph (79-86 total myomeres) and Elops sp. larvae as a low-count morph (74-78 total myomeres). This author also mentioned differences in preanal and predorsal myomeres counts (76-80 versus 68-72 and 66-71 versus 61-66, respectively). Elops saurus morph inhabits the United States coasts to the Gulf of Mexico, while Elops sp. inhabits the Caribbean Sea and the northern coast of South America (Smith & Crabtree, 2002; McBride & Horodysky, 2004; Richardson & Cowen, 2004). Recent studies based on mtDNA cytochrome analysis confirmed the occurrence of two species; the high-count myomeres species remained as E. saurus while the low-count was named E. smithi (McBride et al., 2010).
The juveniles and adults of Elops sp. have been found in tropical and subtropical bays, river estuaries and hypersaline coastal bodies (Cervigón et al., 1992; Joyeux et al., 2004; Richardson & Cowen, 2004; Castro & Bonecker, 2005; Goch et al., 2006; Rodríguez-Olarte et al., 2006; Azevedo et al., 2007). In northern South America (~10°N), this species is collected in 5 to 10% of total catches (Rodríguez-Olarte et al., 2006), while in eastern South America (~23°S) it is less abundant (<1% total catches) (Azevedo et al., 2007; Vasconcellos et al., 2011). Proper knowledge about abundances of Elops larvae is scarce because most studies of ichthyoplankton identified leptocephali mainly to the order level (Richardson & Cowen, 2004; Castro & Bonecker, 2005).
Elopidae has a typical leptocephalus larva characterized by a very laterally compressed and transparent body, but the genus differs from anguilliform leptocephali by the presence of forked tail. Adults and early larval stages of Elops are captured in oceanic waters near the shelf break where spawning seems to occur and then, late larval stages and juveniles enter estuaries (Gehringer, 1959; Govoni & Merriner, 1978; McBride & Horodysky, 2004), and Elops has been recognized...