Molecular phylogeny of black flies (Diptera: Simuliidae) from Thailand, using ITS2 rDNA

Abstract

The sequences of the second internal transcribed spacer (ITS2) of ribosomal DNA (rDNA) were determined for 40 black fly species from Thailand, belonging to 4 subgenera of the genus Simulium, namely Gomphostilbia (12 species), Nevermannia (5 species), Montisimulium (1 species), Simulium sensu stricto (21 species), and an unknown subgenus with one species (Simulium baimaii). The length of the ITS2 ranged from 247 to 308 bp. All black fly species had high AT content, ranging from 71 to 83.8%. Intraindividual variation (clonal variation) occurred in 13 species, ranging from 0.3 to 1.1%. Large intrapopulation and interpopulation heterogeneities exist in S. feuerboni from the same and different locations in Doi Inthanon National Park, northern Thailand. Phylogenetic relationships among 40 black fly species were examined using PAUP (version 4.0b10) and MrBAYS (version 3.0B4). The topology of the trees revealed two major monophyletic clades. The subgenus Simulium and Simulium baimaii were placed in the first monophyletic clade, whereas the subgenera Nevermannia + Montisimulium were placed as the sister group to the subgenus Gomphostilbia in the second monophyletic clade. Our results suggest that S. baimaii belongs to the malyschevi-group or variegatum-group in the subgenus Simulium. The molecular phylogeny generally agrees with existing morphology-based phylogenies.

Population genetic structure of Simulium degrangei (Diptera: Simuliidae) from Western Carpathians

“…The analyzed populations do not differ in proportion of nucleotide bases, where A and T dominate with an average of 65.86% which is a phenomenon typical for arthropods (Hebert et al 2003) but also recognized in blackflies (Xiong & Kocher 1991;Morales-Hojas et al 2002b;Thanwisai et al 2006;Rivera & Currie 2009). This percentage is similar to that found in the same gene in Simulium reptans Linnaeus, 1758, Simulium galeratum Edwards, 1920 (Day et al 2008) and many North American species Finn & Adler 2006;Rivera & Currie 2009).…”

Identification of astigmatid mites using ITS2 and COI regions

“…Analyses of the sequences (Alvarez and Wendel 2003;Webster et al 2004;Marrelli et al 2006;Thanwisai et al 2006;Ben-David et al 2007) showed that such a method could be potentially used to identify astigmatid mites with similar morphological characteristics. When the mites were cloned, as in B. tropicalis described here, few or no differences were observed in their ITS2 regions.…”

Phylogenetic analyses of mitochondrial and nuclear data in haematophagous flies support the paraphyly of the genus Stomoxys (Diptera: Muscidae)

“…Mitochondrial DNA (mtDNA) has been widely used in systematic and many universal PCR primers are available for genes like COI and CytB (Avise, 2004). The ITS2 region is easy to amplify and have been used in previous phylogenetic studies of Diptera (Hwang, 2007;Thanwisai et al, 2006). This work explores congruence and information content within the different molecular datasets analysed using probabilistic methods of phylogenetic reconstruction.…”