FISHERY BULLETIN: VOL. 82, NO. 4 



males 97.5 cm FL; commonly 50-70 cm; age at first 

 maturity of both sexes 45 cm (Postel 1955a). 



Color pattern. — Upper parts of body bluish, belly 

 silvery, sides marked with several poorly defined 

 rows of elongate spots (Fig. 69). First dorsal fin 

 black anteriorly and along distal margin posteri- 

 orly, white at base. 



There are drawings of S. tritor in Postel (1955a: 

 pi. 2) and Poll (1959:fig. 34), Collette (1981: 

 Scombm 7), and Seret and Opic (1981:333). 



Biology. — Sexual maturity in both sexes of S. 

 tritor occurs from April to October in Senegal 

 (Postel 1955a). Postel (1955a) reported 1 million 

 eggs in a 95 cm FL female. Juveniles have been 

 seined along the shore near Dakar in July (Postel 

 1955a). Seven larvae 3.5-8.1 mm were caught in 

 September, December, February, and March, 

 south of the Ivory Coast at water temperatures of 

 23.2°-26°C and salinities of 34.38-35.45L (Zhu- 

 dova 1969). Three larvae identified as S. tritor 

 were reported from a station track from Dakar to 

 Recife (Zharov and Zhudova 1967), but this distri- 

 bution seems highly unlikely. In Lagos Lagoon, 

 Nigeria, stomach contents of 24 of 26 specimens of 



S. tritor with food contained the clupeid Ethma- 

 losa fimbriata (Fagade and Olaniyan 1973). No 

 sexually mature stages of S. tritor were found in 

 the lagoon so Fagade and Olaniyan concluded that 

 the lagoon served as a feeding ground for this and 

 other piscivorous fishes that could tolerate the 

 reduced salinity of the lagoon. 



Interest to fisheries. — Taken throughout the Gulf 

 of Guinea, but catches are reported only for Ghana 

 and Angola in the period 1979-82. Most of the 

 catch is reported for Ghana, 1,569 to 4,412 t/yr 

 (FAO 1984). 



Distribution. — Eastern Atlantic, concentrated in 

 the Gulf of Guinea from the Canary Islands 

 (Mather and Day 1954; MCZ 26416), West Sahara 

 (Stassano 1890), and Dakar, Senegal (original 

 description), south to Baia dos Tigres, southern 

 Angola (Fig. 49). Accidental and rare in the 

 Mediterranean Sea (Tortonese 1949, 1956), with 

 several extant specimens from Nice (NHMV 

 14599, MSUF M.1665), Villefranche, and Palermo 

 (Tortonese 1975). 



Material examined. — Total 49 (69-658 mm FL). 



TABLE 30. — Summary of morphometric data of Scom- 

 beromorus tritor. FL = fork length, HL = head length. 



meas.: 40 (102-658): N. Mediterranean (2); Ca- 

 nary Is. (1); Spanish Sahara (1); Senegal 

 (4, *C. tritor), Guinea (1); Sierra Leone 

 (5); Liberia (5); Ivory Coast (10); Ghana 

 (5); Nigeria (4); Angola (2); "West Afri- 

 ca" (1, *S. argyreus Fowler). 



counts: 49. 



diss.: 10 (394-600): Ivory Coast. 



RELATIONSHIPS 



After comparing the species of Scomberomorus 

 with each other and with Grammatorcynus and 

 Acanthocybium (Comparative Morphology), all 

 the characters that differentiated species or 

 genera were listed. Character polarities were 

 determined by considering the character state 

 present in Grammatorcynus to represent the ple- 

 siomorphous condition. Scomberomorus, Acan- 

 thocybium, the Sardini, and the Thunnini have 4 

 or 5 caudal vertebrae supporting the caudal fin 

 and 37 or more total vertebrae. These derived 

 characters indicate that these taxa form a mono- 

 phyletic group within the Scombridae. Gramma- 

 torcynus lies between the Scombrini and the 

 higher scombrids and is clearly more primitive 

 than Scomberomorus because it has, as in the 



670 



