DEVELOPMENT OF LARVAE OF THE FRENCH GRUNT, HAEMULON FLAVOLINEATUM, AND COMPARATIVE DEVELOPMENT OF TWELVE SPECIES OF WESTERN ATLANTIC HAEMULON (PERCOIDEI, HAEMULIDAE) Kenyon

Developmental series were constructed for postflexion larvae of 6 and early juveniles of 12 species of western Atlantic Haemulon from reared wild-caught larvae; seine, nightlight and rotenone collections; and museum material. Number and placement of midline melanophores, combinations of typical dorsal and anal ray frequencies, timing and morphologies of caudal spot appearance, and preopercular spination aid identification of post flexion larvae. Early juveniles (ca. 15-40 mm standard length) show a distinctive pigment pattern characterized by a dark midlateral stripe, two to four dorsolateral stripes and a caudal spot. During this stage, important characters such as caudal spot morphologies, spot placement relative to the caudal base, midlateral stripe presence, stripe/spot connections and squamation patterns often show significant ontogenetic changes not accounted for in previous studies. Several new characters, particularly the length of the third dorsolateral stripe, greatly aid field identification. A key accommodating extreme morphological similarities and ontogenetic variability of Haemulon early juveniles is presented. Developmental morphology, pigmentation and osteology of H.jlavolineatum from 6.2 mm SL were examined in detail. Larvae do not possess pelvic, ventral gut or dorsal midline pigment. A dark caudal spot showing a dorsoventral constriction is centered over the caudal base by 7.5-8 mm. Melanophores appear on the snout and operc1e at 8.5-9.5 mm and anterior caudal peduncle at 10-11 mm and grow caudad and rostrad, respectively, to form a complete midlateral stripe by 13-13.5 mm. The premaxilla, maxilla, dentary and c1eithrum ossify by at least 6.2 mm. Two radial cartilages were placed distally below the parhypural and second preural haemal spine from 6.6 mm to at least 40 mm. Fins developed full complements of elements in the following sequence: principal caudal, anal and second dorsal (6.6-6.8 mm); first dorsal (8 mm); pelvics (9.2 mm); and pectorals (10 mm). Postflexion larvae of H. parrai, H. plumieri and H. bonariense show greatest melanophore concentrations, while H. jlavolineatum. H. melanurum and H. chrysargyreum show the least. Ventral midline melanophores are present in all species. Dorsal midline and midlateral melanophores are also present in larvae of several species. The caudal spot appeared in all species examined by 7-10 mm. In early juveniles, several relatively distinct patterns oflateral stripe and caudal spot pigmentation exist within the genus. Limited comparisons of osteological development and variability in squamation are also discussed. Developmental comparisons and a reexamination of adult characters do not fully support prior hypotheses of intrageneric relationships. Of 12 New World genera in the percoid family Haemulidae (=Pomadasyidae), Haemulon is the most speciose. Eighteen Haemulon species are recognized: 13 from the western Atlantic (the grunts, white margate, tomtate, sailors choice and cottonwick), 4 from the eastern Pacific and 1 amphi-American species. These are among the most abundant of western Atlantic reef fishes (Starck and Davis, 1966; Bohlke and Chaplin, 1968), are a major biomass and dollar-value component of many regional fisheries (Huntsman et al., 1983; Weiler and Suarez-Caabro, 1980; Cervigon, 1966), and can be subject to localized overexploitation (Appeldoorn and Lindeman, 1985). The genus is also of considerable ecological importance