WATSON ET AL.: TRACHINOIDEA 



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Table 134. Summary of Early Life History Information Available for Trachinoid Fishes. 



Cheimarrhichthyidae (McDowall, 1973c). Six of the seven re- 

 maining families spawn small to moderate (0.70-2.45 mm di- 

 ameter), spherical, single pelagic eggs (Table 135). McDowall 

 (1973c) suggested a pelagic spawning mode for Cheimar- 

 rhichthyidae as well, unusual for the suggested riparian spawn- 

 ing habitat but consistent with the close relationship, or identity, 

 of Cheimarrhichthyidae with Mugiloididae. All pelagic eggs have 

 oil droplets (most have only one, 0.16-0.26 mm in diameter) 

 and all except some Uranoscopidae have smooth, unsculptured 

 chorions. Incubation periods range from 2 to 6 days and larvae 

 are not well developed at hatching (Trachinidae are somewhat 

 better developed, with pigmented eyes and pelvic buds). 



Demersal egg masses (750-1,000 eggs) are produced only by 

 the Trichodontidae (Table 135). These eggs are large (3.52 mm 

 in diameter), slightly flattened, with an unsculptured chorion 

 and no oil droplet. Incubation is estimated at about one year 

 (Mariiave. 1981) and larvae are well developed at hatching. 



Larvae 



Larval stages are unknown for the Cheimarrhichthyidae and 

 Leptoscopidae. The described trachinoid larvae display only a 

 few unifying characteristics: (1) all are pelagic, hatching at ca. 

 2-15 mm (Table 1 36); (2) they pass through no specialized stages 

 (except the gargaropteron juvenile stage of the chiasmodontid 

 genus Kali): and (3) they metamorphose gradually to the de- 

 mersal juvenile stage at a small to moderate size (ca. 10-60 

 mm). 



Mo/7)/)o/og)'. — Morphology is quite variable; however, larvae 

 are either relatively long and slender (Fig. 299: Trichodontidae, 

 Chiasmodontidae, Percophididae, Trichonotidae, Creediidae) 

 or rather robust (Fig. 300: Champsodontidae, Mugiloididae, 



Trachinidae, Uranoscopidae). All the robust larvae and one of 

 the slender types (Trichodontidae) have somewhat rounded heads 

 with relatively short snouts. Preanal length in both types usually 

 is not more than 50% of standard length (60% or more in Cree- 

 diidae and Trichonotidae) and changes little during develop- 

 ment. Head and body spination are extremely variable. Pre- 

 opercular spination is known for six families: Trichodontidae, 

 Chiasmodontidae, Champsodontidae, Mugiloididae, Creedi- 

 idae, and Trachinidae. Champsodontid larvae develop a serrate 

 crest on the snout and head during the postflexion period, and 

 chiasmodontid larvae (except Kali: R. J. Lavenberg, pers. comm.) 

 develop small body spicules (Fig. 299) just before or during 

 notochord flexion. 



Pigmenlalion. — Pigmenlalion of trachinoid larvae is quite vari- 

 able, from nearly absent to quite intense (Table 137). Larval 

 champsodontids, mugiloidids, trichonotids, and creediids re- 

 main lightly pigmented throughout development, while larval 

 trichodontids, chiasmodontids. trachinids, and uranoscopids 

 may become rather heavily pigmented. Pigmentation usually 

 increases with increasing larval size; trichonotids and creediids 

 change little in pigmentation with growth. 



Head. — Eyes are pigmented at hatching for the demersally- 

 spawned Tnchodontidae, and for two of the six families with 

 pelagic eggs (Table 137). Pigmentation is present at hatching, 

 or subsequently develops, over the brain in five families. The 

 degree of pigmentation of other areas of the head is variable. 



Gut. — Pigmentation typically is present dorsally over the gut 

 and swim bladder throughout larval development (absent only 

 in creediids and postflexion trichonotids). Other gut pigment is 

 variable. 



