PHYLOGENETIC RELATIONSHIP OF SPECIES IN THE GENUS ASPIDOGASTER (ASPIDOGASTRIDAE, ASPIDOGASTRINAE) IN CHINA AS INFERRED FROM ITS rDNA SEQUENCES

Five species in the genus Aspidogaster have been reported in China, and four species, i.e. A. conchicola Bare, 1827, A. limacoides Diesing, 1834, A. ijimai Kawamura, 1913 and A. chongqingensis Wei, Huang et Dai, 2001, were obtained to examine their phylogenetic relationship by comparing ITS rDNA sequences. The length of the ITS-1 and ITS-2 sequences ranged from 728 to 877 bp and 518 to 645 bp, and the G + C content from 50.1 to 52.3% and 49.2 to 52.2%, respectively. Both maximum likelihood (ML) and neighbour-joining (NJ) phylogenetic trees revealed three well-supported main clades, which correspond respectively to A. limacoides and A. chongqingensis, A. ijimai, and A. conchicola, with A. conchicola located at the base of the phylogenetic tree. The group containing A. chongqingensis and A. limacoides formed the sister taxon to A. ijimai with 100% of bootstrap value. It was considered that A. chongqingensis and A. limacoides should be the closest, and they should be closer to A. ijimai than to A. conchicola. In addition, host specificity of Aspidogaster spp. in China was discussed.