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ONTOGENY AND SYSTEMATICS OF FISHES-AHLSTROM SYMPOSIUM 



Table 167. Larval Characterlstics of 18 Species of Gobiesocids for which Larvae are Known Organized into Slibfamilies after Briocss 

 (1955). See Fig. 338 for abbreviations for regions of pigmentation (coding of pigment patterns depended on illustrations in most species. * denotes 



counts on older postflexion larvae). 



Pigmentation (left side) 



Species/Reference 



Conidens lalicephalus (Shiogaki and Dotsu, 197 Id) 



Trachelocfusmus inelobesia (Ruck. 1971) 



Trachelochismus pinnulatus (Ruck, 1973b) 



Lepadogasler lepadogasier (G\i\Xc\. 1888; Russell, 1976) 



Lepadogasler candolei {Guitel, 1888; Russell, 1976) 



Apletodon microcephalus (G\i\xe\. 1888; Russell, 1976) 



Diplecogasler bimaculala (Guileh 1888; Russell, 1976) 



Diplocrepis pumceus (Ruck, 1973b) 



Gaslroscyphus hecloris (Ruck, 1976) 



Gastrocyalhus gracilis (Ruck, 1976) 



Acrytops beryllinus (Gould, 1965) 



Gobiesox maeandricus (Allen and llg, 1983) 



Gobiesox rhessodon (Allen, 1979) 



Gobiesox slrumosus (Kuny&n, 1961; Dovel, 1963) 



Rimicola muscarum (Allen, 1979) 



Lepadichthys frenatus (Shiogaki and Dolsu, 1971b, c) 



Aspasma minima (Shiogaki and Dotsu, 1971a) 



Aspasmichlhys ciconiae (Shiogaki and Dotsu, 1972d) 



The early life history stages of draconettids are unknown at 

 this time. Therefore, the Draconettidae will receive little further 

 attention in this paper. 



The Gobiesocidae (clingfishes) is a diverse group of primarily 

 shallow water or intertidal marine (although a few species are 

 freshwater) fishes consisting of about 33 genera and 100 species. 

 Clingfishes occur along tropical and temperate shores in the 

 Atlantic, Indian and Pacific Oceans. Distinguishing character- 

 istics of gobiesocids include: pelvic fins modified into a thoracic 

 suction disc; pelvic fin with one small modified spine and four 

 or five soft rays; single dorsal fin without spines; no basibran- 

 chials; vertebrae 25-54 (or 78 if the genus Alabes is included, 

 see below); lateral line confined to head; two postcleithra; hy- 

 purals fused into a single plate. Most species are small (normally 

 <70 mm), but a few attain relatively large size (up to 300 mm) 

 (Nelson, 1976). Eight subfamilies are recognized (Briggs, 1955). 

 Springer and Fraser (1976) synonymized the family Cheilo- 

 branchidae (=Alabetidae) with the Gobiesocidae based on shared 

 specializations particularly of the structure of the joint between 

 the supracleithrum and cleithrum. If valid, this synonymy adds 

 one more genus (Alabes) and four species to the Gobiesocidae. 



Development 



Eggs 



Spawning occurs in rocky intertidal or subtidal areas. Eggs 

 are demersal and are attached to the underside of rocks or shells 

 or on kelp blades. The adults (usually the male) guard the eggs 

 during development. Eggs are ovate to ellipsoidal in shape and 

 range from about 0.7 to 1.9 mm in greatest dimension (Table 

 166). The monolayered egg masses usually contain between 100 

 and 600 eggs with some reports of up to 2,500 eggs in a patch 

 (Gobiesox strumosus) (Table 166). The initial coloration of the 

 eggs ranges between purple and green (with pink, yellow and 

 orange predominating). Eggs contain anywhere from one to 100 



oil globules depending on species and stage of development. As 

 development proceeds, oil globules tend to coalesce ultimately 

 into one. 



Larvae 



Larvae of 18 species of gobiesocids have been described in 

 varying detail (Table 167). Larval series are available for 10 of 

 these species. Larvae are well developed at hatching and possess 

 functional jaws, fully pigmented eyes, body pigment similar to 

 that of later larval stages and a small (sometimes bilobed) yolk 

 sac in most species which is probably absorbed soon after hatch- 

 ing. Size at hatching ranges from 2.4 mm in Gobiesox strumosus 

 to 6.8 mm in G. maeandricus and appears to be related to egg 

 size and maximum size of the adults (Table 168). Larvae are 

 cylindrical and somewhat laterally compressed becoming more 

 robust with growth. All clingfish larvae have long, underslung 

 guts which usually extend beyond the midline of the body (preanal 

 length 50-70% SL) in both pre- and postflexion larvae. Size at 

 notochord flexion was difficult to determine from most of the 

 larval descriptions, but generally ranged between 5.0 and 8.0 

 mm depending on the species (Table 167). Gobiesocid larvae 

 have well-developed swimbladders in the early stages of devel- 

 opment which are located in the dorso-anterior portion of the 

 peritoneal cavity. In several species the swimbladder is hidden 

 by the heavy pigmentation on the dorsum of the gut. No sudden 

 change occurs at settlement; rather, larvae gradually attain ju- 

 venile characteristics. Size at settlement is, therefore, difficult 

 to determine. Juvenile characteristics are attained at a wide 

 range of sizes (6.3-13.0 mm) with a trend toward larger species 

 "settling" at larger sizes (Tables 167 and 168). Presumably, the 

 loss of the swimbladder occurs during settlement. 



Most gobiesocid larvae are heavily pigmented. Furthermore, 

 the numbers and patterns of the large, stellate melanophores on 

 the body are species specific, and are invaluable in the identi- 

 fication of species (Figs. 336 and 337). Melanophores occur 

 primarily in the seven regions designated in Fig. 338. Larvae of 



