Abstract: 　Objective To compare the sequence difference of the ribosomal DNA second internal transcribed spacer ITS2) in Anopheles minimus from Yunnan, Hainan, Guangxi of China and from Thailand. Methods Single mosquito′s legs were digested to extract DNA; the rDNA-ITS2 region was amplified by specific primers and the PCR products were purified, sequenced and analysed. Results Two different kinds of ITS2 sequences, temporarily named as An.minimus A and An.minimus C, were found in this study. The length and GC contents of ITS2 region in species A and species C are 481 bp, 54.04% and 483 bp, 54.23%, respectively. Two species differed by 5.8% in the ITS2 sequences owing to 22 fixed nucleotide substitutions and indels. Conclusion Two cryptic species, An.minimus A and An.minimus C, were found in the research localities.

Key words: Anopheles minimus complex, ribosomal DNA, ITS2, sequence