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ONTOGENfY AND SYSTEMATICS OF FISHES-AHLSTROM SYMPOSIUM 



t 1 I L_ 



Fig. 167. Ceratioid larvae. (A) Caulophrynidae, Caulophryme sp., sex ?, 6.6 mm; (B) Neoceratiidae. Neoceratias spinifer. sex ?, 6.3 mm; (C- 

 G) Linophrynidae; (C) Linophnme subgen. Rhizophryme sp., female, 17.5 mm; (D) Haplophryne mollis, metamorphic male, 13.2 mm; (E) 

 Linophryne subgen. Linophryne sp., male, 3.8 mm; (F) Linophryne subgen. Stephanophryne indica, female 8.6 mm; (G) Borophryne apogon, 

 male, 4.3 mm lateral and dorsal views. (All from Bertelsen, 1951.) 



(7.5 mm) this length is reduced to 28% SL, and pelvic fin rays 

 are absent in the two known parasitic males (12-16 mm) as well 

 as in all metamorphosed females (10-109 mm SL). 



Illicium, 2nd cephalic ray and caruncles. — In larvae of all fam- 

 ilies except Caulophrynidae and Neoceratiidae, sexual dimor- 

 phism in the development of the illicium is present. In females, 

 the illicium rudiment is club-shaped and protrudes from the 

 head or from the bottom of a groove in its enveloping skin (Fig. 

 168A, B); in males it is represented only by the tiny subdermal 

 rudiment of the illicial bone. Similarly, the external rudiment 

 of the second cephalic rays of Diceratiidae and Ceratiidae as 



well as the caruncles of the latter family are present in the female 

 larvae and absent in the males (Figs. 168C, D; 169E). 



Among the 16 known Caulophryne and the 1 1 known Neo- 

 ceratias larvae, no sexual dimorphism has been observed (Ber- 

 telsen, 1951). In Caulophryne, in which metamorphosed fe- 

 males lack an escal bulb with photophore but have a well- 

 developed illicium, the rudiment protrudes on the dorsal side 

 of the head in the same position as in other ceratioid larvae 

 (Fig. 167A). In Neoceratias. in which the illicium is completely 

 absent in the metamorphosed females, all larvae have an elon- 

 gated cylindrical illicium rudiment (pigmented in larger larvae 

 (Fig. I67B) slightly protruding, in a position unique among 



