of spinous dorsal and anal fins rounded. Spinous 

 dorsal fin high, unspotted. Nape moderately 

 humped. Anus moderately far from anal-fin origin, 

 the distance between them equal to about one-half 

 the height of the first anal fin. Pectoral fin long in 

 adults, subequal to pelvic fins, reaching beyond 

 curve of lateral line. Isthmial groove present. Eye 

 moderate about 2.9 percent of body length. Verte- 

 brae: 12 precaudal plus 12 caudal. First dorsal -fin 

 elements: 43-48. 



Material examined. CRR-Med-1, male, fairly 

 large but not in spawning condition, 1,600 mm body 

 length, 21.5 kg, Sicily, near Messina, 2 August 1961 

 (specimen not retained). CRR-EAtl-1, female (no 

 well developed ova), 1,570 mm body length, 20 kg, 

 Portugal, trap off Faro, Cape Santa Maria, 27 May 

 1961 (piece of skin and pectoral girdle catalogued as 

 UMML 11076). CRR-EAtl-2, female (no well de- 

 veloped ova), specimen broken, no measurements 

 recorded, 23.5 kg, Portugal by longline off Cape 

 Santa Maria, 9 August 1961. CRR-EAtl-3, female 

 (no well developed ova), 1540 mm body length, 23.5 

 kg, Strait of Gibraltar, 5 October 1961. 



Robins and de Sylva (1960:405-406) presented a 

 key to the known species of Istiophoridae. At that 

 time T. pfluegeri had not been distinguished from T. 

 belone and the reference in the key to T. belone in 

 fact refers to T. pfluegeri. Table 1 contrasts the four 

 Atlantic species of Tetrapturus. 



Taxonomic status. T. georgei is easily separable 

 from other species in the genus by the characters 

 given in the diagnosis and in Table 1. Although in 

 some features it is intermediate between belone and 

 albidus, it is extreme or unique mothers so that it can 

 not be a hybrid between them (see below). With so 

 few specimens examined little can be said of varia- 

 tion and certainly nothing is known of its population 

 structure. 



Common names. Roundscale spearfish is pro- 

 posed as the English common name for the species in 

 recognition of its peculiar lateral scales . Lowe ( 1 840) 

 referred to itaspeito. Albuquerque (1956) and others 

 have used peto, but they have failed to distinguish 

 istiophorid species, and peito or peto may be taken 

 as comparable to the more general English word 

 billfish rather than as a name for any one species. 



Morphology. Morphometric data are presented in 

 Table 2. Fin- ray counts are (in each instance the 

 order of presentation is Med-1, EAtl 1, 2, 3): first 

 dorsal 48, 45, 47, 43; second dorsal -, 7. 6, 6; first anal 

 16, 14, 15, 16; second anal -, 5, 7, 6; pectoral 19, 20, 



20, 19. There were 12 caudal, 12 precaudal, and 24 

 total vertebrae in all four specimens. 



The general body form of istiophorids changes 

 with growth. Because all four specimens of georgei 

 are of nearly the same size, the description below 

 will apply only to adults. Juveniles and earlier life 

 stages are unknown. 



The dorsal profile is concave above the posterior 

 part of the head, the nape being moderately humped. 

 Exclusive of the sheath for the spinous dorsal fin, the 

 dorsal and ventral profiles are nearly parallel. Be- 

 hind this point the body narrows rapidly to the 

 caudal peduncle. The general body form is best 

 seen in Figure 1 . 



The body is fairly robust, being proportionally 

 wider at the pectoral and first anal fin than T. belone 

 and nearly equal to T. albidus in this regard. 



The dorsal fin is moderately high posteriorly, its 

 height at the 25th spine varying widely from 5.0-9.2 

 percent of total length. This is comparable to that of 

 T. belone at the same size and higher than in albidus. 

 The anterior lobe of the spinous dorsal fin is high 

 (18-24 percent body length) and broadly rounded; 

 likewise the first anal fin is high (12-15 percent body 

 length) and broadly rounded. The dorsal fin is com- 

 pletely unspotted. This feature was checked espe- 

 cially on the sheathed portion of the fin where spots 

 will persist even after severe treatment of sun dry- 

 ing, freezing, or preservative. In this regard georgei 

 is similar to pfluegeri, belone. and angustirostris. 

 None of the specimens exhibited bars on the body 

 but these would have disappeared in the frozen 

 specimens, so this condition is uncertain. However, 

 neither belone nor pfluegeri is barred. 



In istiophorids the pectoral fin usually is allomet- 

 ric in growth, sometimes, as in pfluegeri and audax, 

 changing very rapidly from a short fin to long fin 

 condition in a short size range. This fin is long in 

 georgei, but the time or size of changeover is un- 

 known. Presumably juveniles will have short pec- 

 toral fins. 



Figure 1. — Outline drawing of Tetrapturus georgei based 

 on three photographs taken by Raimondo Sara of a speci- 

 men caught off Messina, Sicily, 1961, and with reference 

 to measurements of other specimens (vertical dashed line 

 indicates position of anus). 



56 



