大亚湾海域石斑鱼(Epinephelus spp.)寄生单殖吸虫群落结构研究

THE COMMUNITY STRUCTURE OF MONOGENEANS FROM EPINEPHELUS SPP. IN DAYA BAY, SOUTH CHINA SEA

调查了大亚湾海域13种石斑鱼(Epinephelus spp.)寄生单殖吸虫群落,结果发现有10种鱼感染单殖吸虫,占调查鱼种类的四分之三,检获单殖吸虫16种,隶属于3科5属,其中拟合片虫属(Pseudorhabdosynochus spp.)10种;除鞍带石斑(E.lanceolatus)和拟青石斑(E.fasciatomaculosus)外,8种鱼可分别感染3—7种单殖吸虫;感染单殖吸虫种类最多的是玳瑁石斑(E.quoyanus)达7种,次之是青石斑(E.awoara)和养殖的橙点石斑(E.bleekeri)均感染6种;各单殖吸虫种类中,感染强度最大的是拟合片虫(P.serrani))(棕点石斑,E.fuscoguttatus)128只/尾,次之是石斑拟合片虫(P.grouperi)(青石斑)62只/尾,接下来是斜带拟合片虫(P.coioidesis)(大斑石斑,E.macrospilos)59只/尾和杯阴拟合片虫(P.cupatus)(玳瑁石斑)49只/尾;平均密度最高的是棕点石斑上检获的拟合片虫128只/尾;在检获的16种单殖吸虫中,8种可分别寄生于2种或2种以上石斑鱼,石斑鳞盘虫(Diplectanum grouperi)和拟合片虫在6种石斑鱼上都能检获,符合广寄生单殖吸虫种特征。有5种鱼检查尾数5尾以上的,其中玳瑁石斑单殖吸虫感染率最高62.07%,其内群落的物种丰富度与宿主体长呈显著正相关。

The community structure of monogeneans in Epinephelus spp. from Daya Bay, South China Sea was studied, Thirteen species of Epinephelus spp. （12 wild species and 2 species cultured-cage） were studied, from which 16 mongenean species, belonging to 5 genera of 3 families were found in 10 species of Epinephelus spp., more than three fourth. Except for E. lanceolatus and E. fasciatomaculosus, every of 8 species of fish severally harboured 3 to 7 species of monogeneans. In the species richness： 7 in E. quoyanus and 6 in E. awoara and E. Bleekeri; in intensity： 128 parasites/fish for P. serrani （E. fuscoguttatus）, 62 for P. grouperi （E. awoara）, 59 for P. coioidesis （E. macrospilos）, and 49 for P. cupatus （E. quoyanus）; the most abundance is P. serrani （E.fuscoguttatus） reached at 128 parasites per fish. Among the 16 species of monogeneans, 8 could parasitize more than 2 fish species. Diplectanum grouperi and Pseudorhabdosynochus serrani were detected from 6 fish species in the study. Among 5 fish species screened for over 5 individuals, E. quovanus was the most prevalence of 62.07%, in which the species richness of ectoparasites in E. quoyanus at infracommunity level was significantly correlated positively with the size of host.