LAUSR

The black rockfish (Sebastes schlegelii) has a viviparous reproductive pattern and long-term sperm storage. Multiple paternity is frequently reported in this species. Six polymorphic microsatellite markers were applied to genotype 23 pregnant females (11 wild and 12 cultured) and 645 of their embryos, which were collected from the coast of the Shandong Peninsula in China. The number of sires and the quantity of paternal contributions for each brood were estimated. The results of a cultured group from Japan were reanalysed for comparison and illustration as a quoted group. Multiple paternity was detected in 10 (90.9%) of 11 broods in the wild group, 11 (91.7%) of 12 broods in the cultured group, and eight (88.9%) of nine broods in the quoted group. The number of sires in the cultured group appears to be significantly larger than that of the quoted group (P = 0.030), but the difference between the wild and the cultured groups was not significant (P = 0.219) nor was that between the wild and the quoted groups (P = 0.146). Additionally, in the 29 multiply sired broods, 22 broods were significantly skewed from equal paternal contributions, indicating that sperm competition and cryptic female choice might play key roles in the post-copulatory paternity biasing of this species. Furthermore, within the quoted data, the male was distinctly older than the female in 16 of 18 (88.9%) copulation pairs, demonstrating that females are apt at selecting older males to mate with. These results may provide some guidance or knowledge for artificial breeding, the evolutionary mechanism of polyandry, and sexual selection in black rockfish.