FISHERY BULLETIN: VOL. 82, NO. 4 



described fresh specimens taken in Wakasa Bay 

 in the Sea of Japan. Body greyish blue dorsally, 

 silvery white laterally and ventrally Several 

 longitudinal rows of small brownish spots scat- 

 tered rather densely along lateral median line. 

 First dorsal fin membrane black. Pectoral, second 

 dorsal, and caudal fins dark brown. Pelvic and 

 anal fins silvery white. 



There are good illustrations of a specimen from 

 the North Pacific in Kishinouye (1923:fig. 61) and 

 of one from India in Jones and Silas (1962:fig. 3). 

 There are photographs of specimens of S. gut- 

 tatus from India in Jones and Silas (1964:pl. 7) 

 and Silas (1964:pl. 2), and there is a good photo- 

 graph of a specimen from the Sea of Japan in 

 Nakamura and Nakamura (1982:fig. IB). A good 

 color photograph of a specimen from the Persian 

 Gulf is included in Kuronuma and Abe (1972: 

 pi. 17). 



Biology. — Little is reported in the literature 

 about movements and migration of S. guttatus 

 but it appears to be less migratory than S. 

 commerson. Possible movements in the Gulf of 



Thailand might be deduced from seasonal changes 

 in peak fishing months along the coast of Thai- 

 land. These peaks are November-December in 

 eastern Thailand, late December-January in the 

 northern part of the Gulf, and January-March in 

 the western part of the Gulf (Tongyai 1970). 

 Based on occurrence of ripe females and size of 

 maturing eggs, spawning probably occurs from 

 April to July around Rameswaram Island be- 

 tween India and Sri Lanka (Krishnamoorthi 

 1958). Ripe females 32.5-46.5 cm FL were taken 

 in Thai waters in May. Larvae and juveniles have 

 been reported from Indonesian and Indian waters 

 but apparently the only certain accounts are 

 those of Jones (1962) and Jones and Kumaran 

 (1964) who illustrated four postlarvae (14.8, 22.9, 

 41.2, and 66.8 mm). As with other species of 

 Scomberomorus , the food is primarily fishes. Ju- 

 veniles in India feed mainly on teleosts, particu- 

 larly clupeoids such as Anchouiella (Venkata- 

 raman 1961; Kumaran 1964; Rao 1964). Adults 

 also feed mainly on teleosts with small quantities 

 of crustaceans and squids (Thailand — Tongyai 

 1970, India — Rao 1964). Anchovies are particu- 



FIGURE 55. — Ranges of five 

 Indo-West Pacific species of 

 Scomberomorus: S. guttatus, 

 S. koreanus, S. semifascia- 

 tus, S. queenslandicus, and 

 S. multiradiatus. 



634 



