FISHERY BULLETIN: VOL. 70, NO. 4 



Table 23. — Familial composition of Lophiiform larvae taken on the second multivessel 

 EASTROPAC survey, summarized by vessel pattern. 



equator. Most larvae of Syacium were under 

 5 mm in standard length, and few were as large 

 as 9 mm. At the latter size, the adult comple- 

 ment of fin rays were present in all fins except 

 the pectoral, and the vertebral column was com- 

 pletely ossified. The vertebral count in speci- 

 mens examined was 10 + 25. 



54. CYNOGLOSSIDAE 



(56 occurrences, 362 larvae) 



Larvae of Symphurus spp. were taken in a 

 broad coastal band between Manzanillo, Mexico, 

 and northern Peru. Symphurus larvae were 

 taken in slightly less hauls than on ETP I (56 

 versus 63 occurrences), but in slightly larger 

 numbers (362 versus 304 larvae). Two kinds 

 of Symphurus larvae were widely distributed, 

 and three or four additional kinds occurred spar- 

 ingly. Of the two common forms, one developed 

 two elongated dorsal rays and the other six elon- 

 gated dorsal rays. 



56. LOPHIIFORMES 



(114 occurrences, 243 larvae) 



Lophiiform larvae were accumulated during 

 the identification and enumeration of ETP II 

 larvae, and then studied as a unit. Ten families 

 were represented (Table 23) . All but two of the 



specimens belonged to the subfamily Ceratioidei, 

 a group of fishes whose ontogeny and taxonomy 

 were dealt with in the impressive contribution 

 of Bertelsen (1951). Ceratioid fishes have the 

 most striking sexual dimorphism found in fishes. 

 The males are parasitic in some ceratioids, free- 

 living in others, but always quite small. Bertel- 

 sen showed that sex can be determined in the 

 late larval stage; a papilliform illicium develops 

 on the head of the female, but not on the male. 

 A major achievement of Bertelsen was defining 

 the distinguishing characteristics of larvae of all 

 10 ceratioid families. His work makes it pos- 

 sible to identify larger ceratioid larvae to the 

 family level with assurance; however, small cer- 

 atioid larvae are much more difficult to identify 

 because they have few distinguishing characters. 

 Although Bertelsen worked out life history se- 

 ries to the generic or species level within all cer- 

 atioid families, ontogeny of the less common gen- 

 era and species still remains unknown. 



The ceratioids are a particularly difficult 

 group in which to work out new developmental 

 series. These cannot be based on larvae alone 

 but must include transforming and adolescent 

 specimens, preferably of both sexes, as well as 

 adults. The EASTROPAC material, almost ex- 

 clusively larvae, is inadequate for this purpose. 

 Distributions of larvae are shown for five cer- 

 atioid families (Figure 18), as noted in the dis- 

 cussion of families. Most kinds of ceratioid lar- 

 vae are quite rotund, hence aptly described as 

 butterballs. 



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