Reproductive Biology of Male Saurida Tumbil in Persian Gulf (Bushehr Province)

Some biological aspects of Greater lizardfish (Saurida tumbil) caught on the Iranian shore of the Persian Gulf (Bushehr Province) were studied from February 2007 to February 2008, by regular monthly collections to gain a deeper knowledge about this commercial species. A total of 691 specimens, including 39 immature, 114 males and 538 females were collected. The mean of the sex ratio was 1:5 (M:F) which was inverse in juvenile where males were the dominant group. For age determination, scales in all specimens and for comparison, otoliths in some, were used. The total length of fish ranged from 25.5 to 53.5 cm in males and the total weight of fishes ranged from 116 to 1125 g. The curvilinear relationship between the total length and total weight was w=0.0093 L2.9369 for males. Histological studies and monthly distribution of GSI, showed that the GSI values have two peaks; the first and highest in May and the second and smallest in October. The minimum GSI was determined in December. It was found that male Saurida tumbil reach the first sexual maturity at 25.5 cm. Sections with 5-7 µm thick were stained with Hematoxyline-eosin for microscopic examinations. In the histological study, spermatogonial proliferation stage, spermatogenesis, prespermiation and degeneration stages were observed.