Complete Mitochondrial Genome of Ovophis makazayazaya (Viperidae, Crotalinae) and Phylogenetic Analysis

This research sequenced and annotated the complete mitochondrial genome of Ovophis makazayazaya and assessed its phylogenetic placement within Crotalinae. The complete mitochondrial genome of O. makazayazaya was determined to be 17,230 bp in length, comprising 13 protein‐coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and 1 mitochondrial control region (D‐loop). The base composition of the mitochondrial genome of O. makazayazaya is as follows: A (32.0%), T (25.2%), C (29.7%), and G (13.1%). The nucleotide composition exhibited a significant AT bias (57.2%). Among the 13 protein‐coding genes, only ATG, ATT, GTG, and ATC serve as the initiation codons of protein‐coding sequences. The termination codons are mainly TAA, AGA, and AGG; while ND1, ND2, COX2, COX3, ND3, and CYTB terminate with incomplete stop codons (e.g., T‐‐). All 22 tRNAs formed the canonical cloverleaf structure except tRNA‐Ser(AGY), which lacked the DHU arm. All PCGs had Ka/Ks < 1, consistent with purifying selection; p‐distance values were < 1 across genes. Phylogenetic analyses based on the concatenated sequences of 13 mitochondrial protein‐coding genes recovered O. makazayazaya within Crotalinae in both Bayesian inference and maximum‐likelihood trees. In the present mitochondrial phylogeny, O. makazayazaya was recovered close to Protobothrops , supporting its phylogenetic placement among Asian crotaline pitvipers. Because only one Ovophis species was included in the present mitogenomic dataset, this result should be interpreted as evidence for the placement of O. makazayazaya within Crotalinae rather than as a direct test of Ovophis monophyly. Together, the mitogenomic features and phylogenetic results provide a useful reference for comparative analyses of crotaline systematics, mitochondrial genome evolution, and future phylogenetic studies of Asian pitvipers.