A new species of Papuan groundsnake (Squamata: Colubridae: Lielaphis) from New Guinea

The recently resurrected genus Lielaphis (Squamata: Colubridae) is comprised of 19 medium-sized, terrestrial snakes collectively regarded as groundsnakes. Although found primarily in New Guinea, a biologically megadiverse region with high conservation priorities, Lielaphis remain poorly studied due to their largely homogenous appearance, elusive nocturnal nature, limited records, and complex taxonomic history, leaving high potential for undescribed species still existing within this group. Using high-throughput sequence data of 12 previously described species of Lielaphis and representatives of its sister taxon, Stegonotus, we apply an integrative approach combining genetic analyses with morphological examinations using vouchered specimens to explore the cryptic diversity of Lielaphis. We place particular emphasis on populations occurring on and adjacent to mainland New Guinea. We identify both molecular and morphological evidence for a new species, Lielaphis slashi sp. nov. from the northeastern lowlands of mainland New Guinea, bringing the number of Lielaphis species to 20, along with a potential range extension of L. aplini. Despite the recent resurgence of interest in New Guinea’s snake diversity, our findings highlight persistent knowledge gaps, emphasizing the need for more comprehensive taxonomic studies of the speciose New Guinea herpetofauna.