348 



ONTOGENY AND SYSTEMATICS OF FISHES-AHLSTROM SYMPOSIUM 



Table 91. Continued. 



Halching 

 length (mm) 



Cy. (Cy.) opisthops hiraii 



Cy. (Poec.) poecilopterus 

 Cy. {Poec.) slarksi 

 Exocoetus monocirrhus 



E. ohlusirostris 

 E. volitans 

 Fodiator aculus 

 Hirundichthys (D.) 



albtmaculatus 

 H. (D.) marginatus 

 H. (D) rondeteti 

 H. (//.) affinis 

 H. (H.) coromandelensis 



H. (//.) o.xycephalus 

 H. (H.) speculiger 

 Parexocoelus brachyplenis 



brachyplerus 

 P. mcnto memo 



Prognichlhys gibbifrons 

 P. sealei 



Exocoetoidei 



Defined by six characters by Rosen and Parenti (1981: 16). 

 We here add two developmental characters: oil droplets in egg 

 minute or absent and preanal distance of larvae increased to 

 about 66% of standard length. 



The Exocoetoidei is undoubtedly a monophyletic group. 

 However, vainous opinions have been expressed as to which 

 group within the suborder is the most primitive. A number of 

 authors have considered the Hemiramphidae to be the most 

 generalized family based largely on the fact that needlefishes 

 and primitive flying fishes {Fodiator) pass through an ontoge- 

 netic halfbeak stage during development. Parin (1961) and Ro- 

 sen ( 1 964) supported this viewpoint. On the other hand, Nichols 

 and Breder (1928) and Breder (1932) considered the family 

 Belonidae the most primitive. To resolve the directionality of 

 the "halfbeak" stage (suite four), three additional character suites, 

 each suite consisting of several correlated transformation series, 

 were considered. Apomorphic character states are numbered 

 higher than plesiomorphic states on Fig. 184. 



The first suite involves pharyngeal tooth plate fusion, trans- 

 formation series A-B. State Al is close opposition of left and 

 right fifth ceratobranchial tooth plates characteristic of more 

 primitive Atherinomorpha and the Adrianichthyoidei. State A2 

 is the fusion of left and right lower pharyngeal bones into a tooth 



plate in the Exocoetoidei. Series B state 1 is when the third 

 upper pharyngeals are separated by a gap. State B2 is when they 

 are joined but not fused in the Exocoetoidea. State B3 is the 

 complete fusion of the third upper pharyngeals into a tooth plate 

 in the Hemiramphidae. 



The second suite involves loss of gill arch skeleton bones, 

 transformation series C-D. State CI is presence of the fourth 

 epibranchial, C2 its loss in the Beloniformes. State Dl is the 

 presence of the fourth upper pharyngeal tooth plates, D2 their 

 loss in the superfamily Exocoetoidea. 



The third suite involves reduction in the cephalic lateralis 

 system, transformation series E-F (data from Parin and Astak- 

 hov, 1982). The cephalic system is more complete in the Scom- 

 beresocoidea than in the Exocoetoidea, including the presence 

 of a premaxillary canal (EI), an autapomorphy unique among 

 teleosts. The pre-, supra-, and post-orbital system is continuous 

 across the top of the head in state 1 . There are short interruptions 

 in the system in state 2 in the Belonidae. The postorbital section 

 is lost in state 3 and secondary bony canals are lost in state 4, 

 both charactenstic of the superfamily Exocoetoidea. 



We now return to the fourth suite of transformation series 

 and resolve the directionality of the "halfbeak" stage. The fourth 

 suite includes elongation of upper and lower jaws and presence 

 of barbels in juveniles, transformation series G-I. State Gl is 



Fig. 181. Late larval and early juvenile stages of beloniform fishes. (A) Adrianichthyidae: Oryzias melastigma, 12 mm; (B) Scomberesocidae: 

 Cololabis adocetus. SWFC 7205 J-20.145, 25 mm SL; (C-I) Exocoetidae: (C) Fodiator acutus pacificus. SWFC FB-62-242, 15.4 mm SL; (D) 

 Cheitopogon unicolor. 18.5 mm SL; (E) Cypselurus comatus. 25 mm SL; (F) Exocoetus monocirrhus. SWFC FB-62-203, 27 mm SL; (G) Pare.xocoetus 

 brachyplerus, 43.5 mm SL; (H) Cheitopogon cyanopterus. 54 mm SL; (I) Cheitopogon pinnatibarbatus japomcus. 80 mm SL. From: (A) Job, 1940; 

 (B, C, and F) Original; (D) Gorbunova and Parin, 1963; (E, G and H) Breder, 1938; (F) Kovalevskaya, 1964; and (I) Abe, 1954. 



