The Western Ghats mountain range stretches 1,600 km along the western coast of the Indian peninsula, traversing the states of Gujarat, Maharashtra, Goa, Karnataka, Kerala, and Tamil Nadu. Known for being a biodiversity hotspot, the region is home to almost 30% of India’s biodiversity. Recently, a team of researchers and naturalists from the University of Calicut, the National Centre for Biological Sciences, Dr Vishwanath Karad MIT World Peace University, and the Society for Odonate Studies have discovered two new species of dragonflies that call this region home. Meet Merogomphus aryanadensis from Kerala and Merogomphus flavoreductus from Maharashtra.
These species are morphologically similar to M. tamaracherriensis, a species endemic to the Western Ghats but are set apart by unique features in their body structure and markings. The new dragonflies stand out in their size and specific body features, which are distinct from those already known in the group Merogomphus. Both new species are smaller than other Indian members of the Merogomphus genus and have unique differences in body markings and the shape of certain parts.
The scientists used two main methods, morphological and genetic analysis, to classify the dragonfly as a new species. Using high-resolution cameras and microscopes, the researchers examined and photographed the dragonfly's body. They then compared its physical traits, like size, wing patterns, and marking colours, with those of known species.
The team also collected small tissue samples from the dragonflies and used specialized kits to extract their DNA. They focused on studying a gene named Cytochrome Oxidase I (COI), commonly termed the barcoding gene. Just like barcodes, this gene helps identify differences among species. They compared these DNA sequences with those from known species of the same group, confirming these dragonflies' unique identity. After studying them, the specimens were deposited in the Biodiversity Lab Research Collections at the National Centre for Biological Sciences in Bengaluru.
The newly discovered species have distinct morphological traits that set them apart from other species within the genus Merogomphus. These include differences in body size, caudal appendages, accessory genitalia, and body markings. Such significant differences raise questions about whether these species truly belong to the same genus as previously thought. The genetic analysis also revealed considerable genetic divergence between these new species and other members of the Merogomphus genus. This genetic distance suggests that these species may not be as closely related to their Merogomphus counterparts as previously assumed.
Traditionally thought to be a single genus, the discovery of different morphological traits and considerable genetic variance suggest these dragonflies may belong to an older, different genus Indogomphus. The distribution of Merogomphus species is also geographically disjunct, with members found in the Western Ghats and Indo-China. This unusual distribution pattern, along with the distinct traits observed in the Western Ghats species, suggests that these species may have originally been part of a different evolutionary lineage more closely aligned with Indogomphus. The authors note that these findings question the taxonomic composition of the genus, suggesting a potential realignment with the original genus, Indogomphus.
The study emphasizes the need for comprehensive genetic and biogeographic analysis to gain a clearer understanding of the genus. More specimens need to be collected and studied, and perhaps the current family tree of the genus Merogomphus and Indogomphus should be overhauled. The discovery also underscores the rich biodiversity and endemism of the Western Ghats and calls for further exploration and conservation efforts in the region.
This research news was partly generated using artificial intelligence and edited by an editor at Research Matters