Taxonomy and diversity of scaritinae and trechinae (Coleoptera: Carabidae) of Kerala

Abstract

Scaritinae Bonelli, 1810 and Trechinae Bonelli, 1810 are the two dominant subfamilies among the family Carabidae from Kerala (Divya, 2022; Ashly, 2023). Taxonomic research on the beetle subfamilies Scaritinae and Trechinae in Kerala is still very limited. This lack of detailed studies has left important gaps in our understanding of species boundaries, distribution patterns, and their systematic classification. To address these gaps, the present study undertakes a comprehensive taxonomic investigation of Scaritinae and Trechinae in Kerala. The aim is to strengthen baseline faunistic knowledge and provide a foundation for future ecological and conservation research. Ecological research on the subfamily Scaritinae and Trechinae in India remains sparse and geographically uneven, with no published studies to date from the North Malabar region of Kerala, a biogeographically distinct and ecologically rich zone that is addressed in the present study. The present study was designed for generating ecological data, abundance, richness, diversity, and seasonality of Scaritinae and Trechinae beetles in selected forest and agricultural habitats of North Malabar. These two subfamilies were chosen for focused ecological analysis based on the taxonomic expertise developed during the initial phase of the study, which dealt with the identification, classification, and documentation of Scaritinae and Trechinae species within the family Carabidae. Taxonomic study includes comprehensive coverage of Kerala’s entomofauna, and diversity study was conducted in selected forests and agricultural ecosystems of North Malabar region. Sampling was carried out in the Semi- evergreen Forest (Aralam Wildlife Sanctuary), Tropical- evergreen forest (Ranipuram Forest) and Agricultural habitat (Chambad Agricultural Field), during both rainy and non-rainy seasons. A total of 28 species of Trechinae beetles belonging to three tribes and seven genera were documented from Kerala. Among these, one new species, three species newly recorded from India, 10 species newly reported from south India, and two species were newly reported from Kerala. A total of 22 species of Scaritinae beetles, belonging to three tribes and 11 genera, were documented from Kerala. Among these, two species newly recorded from India, two species newly reported from south India, and one species newly reported from Kerala. These findings highlights the taxonomic significance of the study.