HYPORHAMPHUS AUSTRALIS X HY. 

 MELANOCHIR, A HYBRID HALFBEAK 

 (HEMIRAMPHIDAE) FROM AUSTRALIA 



The purpose of this note is to report the first 

 known occurrence of hybridization in the family 

 Hemiramphidae. According to Schwartz 

 (1972) it is also the first known hybrid within 

 the order Synentognathi (or suborder Exocoe- 

 toidei according to some recent classifications). 

 Three species of sea garfishes (halfbeaks) of 

 the genus Hyporhamphus occur in Australia- 

 New Zealand waters (Collette'): Hy. ihi Fhi\- 

 lipps, the New Zealand garfish or piper; Hy. 



australis (Steindachner), the eastern sea gar- 

 fish; and Hy. melanochir (Valenciennes), the 

 southern sea garfish. The three species are very 

 closely related but differ in numbers of gill 

 rakers, vertebrae, dorsal and anal fin rays, rel- 

 ative length of the upper and lower jaw, and 

 placement of the pelvic fins. They are almost 

 completely allopatric but the ranges of Hy. 

 australis and Hy. melanochir overlap at Eden 

 in southern New South Wales near the Victoria 

 border. 



During a year's study at the Australian Mu- 



' Collette, B. B. The garfishes (Hemiramphidae) of 

 Australia and New Zealand. Unpublished manuscript. 



Table 1. — Numbers of fin rays, gill rakers, and vertebrae in Hyporhamphus australis, Hy. melanochir, and a 



hybrid between the two species. 



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