The complete mitochondrial genome of Homatula pycnolepis (Teleostei, Cypriniformes) in Lantsang River and its phylogenetic analysis.

Homatula pycnolepis is a small-sized benthopelagic fish species in the family Nemacheilidae, superfamily Cobitidea. In this study, the entire mitogenome sequence of the H. pycnolepis has been sequenced by using sanger sequencing method. The circular mitochondrial genome was 16,570 bp in length and contained of 13 protein-coding genes, two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, an origin of light-strand replication (OL), and one displacement loop locus (D-loop). The overall base composition was 30.1% A, 26.4% T, 26.8% C, and 16.7% G with 56.6% AT content. Most genes were encoded on the heavy strand except for ND6 and eight tRNA genes. There were 11 regions of gene overlaps totaling 29 bp and 7 intergenic spacer regions totaling 37 bp. Its structure type was similar to the mitogenome of Cobitidea fishes. Phylogenetic analysis with 33 complete mitogenomes of Cobitidea and 2 Macrognathus fishes in the family of Mastacembelidae suggested that Homatula species clustered as one monophyletic clade and Homatula was closely related to Schistura. Mitogenome information from this study could be a useful basis for conservation and phylogenetics of this species.