DNA barcodes and species delimitation reveal overlooked diversity in Indian cockroaches (Blattodea)

India harbors unique and largely endemic Blattodea (cockroaches) species richness, with 61% endemism. However, existing research primarily focuses on classical taxonomic methods, resulting in significant gap in context to the systematics and geographic distribution of Indian cockroaches. To address this, comprehensive field sampling was conducted and DNA barcoding was employed as part of Integrative Taxonomic Approach (ITA). From 150 specimens, 50 putative taxa were morphologically identified, and 122 DNA barcodes were generated. Species delimitation analyses revealed the possibilities of 86 to 99 genetic lineages, indicating high morphological cryptic diversity and numerous potential undescribed lineages. From these, 43 lineages could be assigned to known species, while 44 remained unnamed, that may include both already documented and potential new species signifying a complex taxonomy. A preliminary time-calibrated phylogenetic analysis suggests that the diversification of Indian cockroaches began ~162 million years ago, coinciding with the geological separation of the Indo-Madagascar plate with Africa. This study establishes foundational DNA barcode library for Indian cockroaches, enabling multifaceted applications and underscores the need for integrative taxonomy to accelerate documenting of overlooked taxa within cockroaches.