Rhaphidophoridae (Orthoptera: Ensifera), commonly known as cave crickets, are a wingless family and considered the most ancient lineage within Tettigoniidea. However, previous molecular phylogenetic studies and morphological hypotheses have shown inconsistencies. Although their fossils have been found in Baltic amber, their systematic placement remains unrevealed. This study reconstructed a comprehensive phylogeny integrating both extant and fossil lineages. Initially, we revealed relationships within extant lineages through molecular phylogenetics including all extant subfamilies for the first time. Subsequently, using a cladistic approach based on morphology, we confirmed the systematic position of fossil taxa †Protroglophilinae with a report of a new species. Integrating molecular and morphological phylogeney by total evidence tip-dating, we present the comprehensive phylogeny of Rhaphidophoridae considering both extant and fossil groups.

The Korean record of Scolytoplatypus mikado Blandford 1893 is originated from Murayama (1929) whereas Wood(1989) synonimyzed S. sinensis Tsai & Huang 1965 as a junior synonym of S. mikado Blandford 1893. In 2010, the authors collected several specimens from Korea and Japan and found considerable morphological differences between S. sinensis and S. mikad the process on the prosternum, the pubescences on the procoxae, and the shape of the male elytral declivity. Comparing the Cytochrome Oxidase I and 16S rRNA gene, we also found the genetical gap between the South Korean specimens (= S. sinensis, with the Japanese sample from Mt. Tsukubasan) and the sample from Mt. Yamizosan, Japan (= S. mikado). Accordingly, S. sinensis Tsai & Huang 1965 is here reinstated.