SPEARFISHES OF THE CENTRAL PACIFIC 



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mens which included all of these spearfishes, we 

 concur with the fishermen tliat these are six 

 clearly distinct and easily recognizable species. 

 All of them are fishes of tlie liigh seas, and seem 

 to be the same in Hawaiian waters as along the 

 Pacific Equator, where we have caught them in 

 considerable numbers. They fit so well tlie 

 descriptions given by Nakamura (1949) that there 

 seems little doubt that they occur also in tlie 

 western Pacific from Japan to Australia. Further- 

 more, the description of the marlin fishing off 

 Acapulco, Mexico, given by Gabrielson and La- 

 Monte (1950) indicates that the Acapulco "black" 

 marlin is similar to the Hawaiian "black" marlin 

 and tliat the "silver" marlin and "striped" marlin 

 of Hawaii also occur in Mexican waters. South 

 of the Equator off Peru, Chile, New Zealand, and 



Australia, there appear to be two common species 

 of marlin: a "striped" marlin comparable to the 

 "striped" of Hawaii, and a "black" marlin, 

 similar to the one called "silver" in Hawaii and 

 "white" in Japan. A third marlin, similar to the 

 "black" marlin of Hawaii and Japan has been 

 described from New Zealand by Griffin (1927) 

 and from Australia by Whitley (1954), but ap- 

 parently it is not as common as the other marlins 

 in the Southern Hemisphere. In the discussion to 

 follow, a single common name will be used for 

 eacli species to avoid confusion. 



The following key ' is based on the subsequent 

 analysis of characters, distribution, and synonomy. 

 Line drawings of spearfishes of different sizes 

 which will aid in identifications are given in figures 

 2 and 3. 



KEY TO THE SPEARFISHES OF THE CENTRAL PACIFIC 



la. Snout broad, flattened and long, pelvic fins absent, one pair of keels on caudal peduncle Xiphiidae. 



Broadbill Swordflsh Xiphias gtadius Linnaeus. 



lb. Snout shorter, nearly circular in cross section, pelvic fins present, two pairs of keels on caudal peduncle 



Istiophoridae 2 



2a. First dorsal fin very high with middle rays longest, about as long as head. 



Sailflsh Istiophorus orienlalis (Temminck and Schlegel). 



2b. First dorsal fin moderate with anterior rays longest, middle rays much shorter than head 3 



3a. Snout short, tip to anterior edge of orbit about equal to length of mandible. Body slender; greatest depth less than 



13 percent of fork length. Not striped on sides. Rarely weighs more than 100 pounds. 



Shortxose Spearfish Tetraplurus angustirostris Tanaka. 



3b. Snout longer, tip to anterior edge of orbit more than 1.3 times length of mandible. Body stouter, greatest depth 



more than 13 percent of fork length. Striped or not on sides. Commonly weighs more than 100 pounds .... 4 

 4a. Pectoral fin rigid, cannot be folded flat against side. Height of first dorsal less than 80 percent of greatest body 



depth, averaging about 60 percent. Pelvic fins 18 to 31 cm., average 26 cm. in fish over 150 pounds. Rarely striped 



on sides; stripes never conspicuous after death. 



Black Marlin ' Istiompax marlina (Jordan and Hill). 



4b. Pectoral fin turns and folds flat against side. Height of first dorsal usually more than 70 percent of greatest body 



depth. Pelvic fins 22-42 cm., average about 33 cm. in fish over 30 pounds. Stripes on sides usually visible for a 



few hours after death 5 



5a. Height of first dorsal lobe less, usually much less, than greatest body depth. Height of first anal fin more than 76 



percent height of first dorsal, average 86 percent. Height of 20th ray of first dorsal 3-9 cm., average 6 cm. above 



fin sheath in fish more than 2 m. fork length. Body stouter, more cylindrical. Stripes usually present, but seldom 



conspicuous after death. 



Pacific Blue Marlin • Makaira ampla (Poey). 



5b. Height of first dorsal lobe more than 90 percent of greatest body depth. Height of first anal fin less than 76 percent 



of height of first dorsal, average 66 percent. Height of 20th ray of first dorsal 7-14 cm., average 10 cm. above fin 



sheath in fish more than 2 ni. fork length. Body more slender, compressed, and tapered. Stripes usually conspicuous 



after death. 



Striped Marlin Makaira audax (Philippi). 



' Refer also to the complete discussions referring to specimens weiehlng less than 50 pounds. 

 ' Wliite marlin of Japan, silver marlin of Hawaii, black marlin of South America, Australia, and New Zealand. 



' Blue marlin of .Atlantic Ocean, blaclt marlin of Hawaii an<l Japan. We follow LaMonte and Marcy (I94I) in the use of the name ampla and have not 

 attemiHed to unravel the tangled synonymy of the Atlantic form. 



