Synopsis on the Biology of the Shortbill Spearfish, 



Tetrapturus angustirostris Tanaka, 1914 in 



the Indo-Pacific Areas 



SHOJI KIKAWA 1 



1 IDENTITY 



1.1 Nomenclature 



1.11 Valid name 



Tetrapturus angustirostris Tanaka, 1914 (Fig. 1). 



Original description: Tanaka, Shigeho. 1914-1915. 

 Figures and descriptions of the fishes of Japan. Dai- 

 ichi Shoin, Tokyo 18:295-318 (1914); 19:319-342 

 (1915). 



1.12 Objective synonymy 



All synonyms that appear in the literature seem to 

 be subjective (See 1.21 below). 



1.2 Taxonomy 

 1.21 Affinities 



Suprageneric 



Phylum Chordata 



Subphylum Vertebrata 

 Superclass Gnathostomata 

 Class Osteichthyes 



Subclass Actinopterygii 

 Order Perciformes 

 Suborder Xiphioidei 

 Family Istiophoridae 



Generic 



Genus Tetrapturus Rafinesque, 1810. 



Original description: Rafinesque, C. S. 1810. 



Carratteri di alcuni nuovi generi e nuove specie di 

 animali principalmente di pesci e piante della Sicil- 

 ia, con varie osservazioni sopra i medesimi. 105 p. 

 Palermo. 



The generic concept of Tetrapturus has been a con- 

 fused one. Hirasaka and Nakamura (1947) divide 

 Istiophoridae into two subfamilies, Tetrapturinae and 

 Marlinae. They place Tetrapturus, Istiophorus, and 

 Kajikia in the former, and Marlina and Eumakaira in 



'Far Seas Fisheries Research Laboratory, Shimizu, Japan. 



the latter. In Tetrapturus, they include a single 

 species, T. angustirostris, and state that T. belone in 

 the Mediterranean Sea and T. brevirostris in the In- 

 dian Ocean may be the same species, or very closely 

 related. Their genus Kajikia embraces two species, K. 

 mitsukurii (Jordan and Evermann), the Indo-Pacific 

 striped marlin, and K. formosana, new species, which 

 was shown later by Ueyanagi (1957) to be the juvenile 

 form of the striped marlin. 



Matsubara (1955) disagrees with Hirasaka and 

 Nakamura (1947) and states that the number of 

 vertebrae and other diagnostic characters they used to 

 establish the subfamilies do not deserve a generic 

 rank. Matsubara also considers Makaira as valid and 

 excludes Kajikia, Marlina, and Eumakaira as syn- 

 onyms of Makaira. According to his classification of 

 Japanese fishes, Tetrapturus includes T. 

 angustirostris, and Makaira includes four species: M. 

 mitsukurii (Jordan and Evermann), the Indo-Pacific 

 striped marlin; M. formosana, now a synonym of M. 

 mitsukurii; M. mazara (Jordan and Snyder), the 

 Indo-Pacific blue marlin; and M. marlina Jordan and 

 Hill, the black marlin. 



LaMonte (1955) states that Tetrapturus can be dis- 

 tinguished from Makaira by its much more slender 

 body, shorter spear, shorter pectorals, lower lobed and 

 evenly high dorsal, and smaller caudal span. She 

 recognizes T. belone Rafinesque, the Sicilian fish, and 

 T. angustirostris Tanaka as valid species of the genus. 



Royce (1957), who analyzed morphometric data 

 from specimens taken in the central Pacific Ocean, 

 states that the variation in the height of the dorsal 

 lobe and the length of the pectoral fins is such that 

 these characters are not useful in distinguishing one 

 species from another. 



With regard to Tetrapturinae and Marlinae as set 

 forth by Hirasaka and Nakamura (1947), Robins and 

 de Sylva (1960, 1963) support this basic dichotomy 

 but state that these subdivisions need not be accorded 

 subfamily rank. To such definitions, they add the 

 character of negative allometry of the snout in the 

 "Tetrapturinae" and positive allometry in the 

 "Marlinae," but deny the aid of the pectoral fins for 

 generic definition because this character, mainly on 

 the basis of which LaMonte separates Tetrapturus 

 from Makaira, shows marked allometry in the spear- 

 fish. Robins and de Sylva state that T. angustirostris, 



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