The ancient, relict Asian scorpion family Pseudochactidae Gromov, 1998 has a disjunct distribution. Five genera and seven species of living pseudochactids are assigned to an epigeic subfamily, Pseudochactinae Gromov, 1998, from Central Asia and South China, and two hypogeic subfamilies, Troglokhammouaninae Prendini et al., 2021, and Vietbocapinae Louren the Khan-Phong, 2000, 2000, 2000-2000. Nha-Kẻ Bàng Karst in the northern Annamite (Trương Sơn) mountains of Laos and Vietnam. The extinct subfamily Chaerilobuthinae Lourenço and Beigel, 2011, comprises one genus and 15 species, thought to be endogeic, from mid-Cretaceous Burmese amber. The discovery and uncertainty regarding the phylogenetic placement of Qianxie solegladi Tang, 2022, from southern China, together with the discovery that Cretaceous-amber Chaerilobuthinae, from the Burma Terrane, is the sister group to the extant pseudocactid subfamily Vietbocapinae, provided an opportunity to restore research and biology. Pseudochactidae, and their adaptation to subterranean habitats in Southeast Asia. In this contribution, pseudocactid phylogeny is reanalyzed using three mitochondrial markers (12S rDNA, 16S rDNA, Cytochrome c Oxidase Subunit I), three nuclear markers (18S rDNA, 28S rDNA, Internal Transcribed Spacer, all morphological characters, p4 for exact 1.3 for morphological characters). taxa and seven examples of species of the extinct Chaerilobuthinae. Divergence time and ancestral range are estimated and the evolution of troglomorphic characters is examined to reconsider how this lineage of “living fossils” spread and diversified. Recent changes in the systematics of Pseudochactidae are confirmed. The four subfamilies, genera and species were monophyletic with high support and the following scheme of relatedness: (Pseudochactinae (Troglokhammouaninae (Chaerilobuthinae + Vietbocapinae). Phylogenetic analyses, reinforced by a multivariate morphometric analysis and pairwise genetic distances, confirm the validity of the Chinese gene, epigeic, epigeic, Qxigean, 2022, which formed a monophyletic group with the epigeic Central Asian genus, Pseudochactas Gromov, 1998, rather than the hypogeic Southeast Asian genus, Troglokhammouanus Lourenço, 2007. Qianxie solegladi is transferred to the Pseudochactinae tree of A revised Chaerilobuthinae diverged from the Indochinese subfamilies, Troglokhammouaninae and Vietbocapinae, in the Early Cretaceous (ca. 117 Ma), consistent with Early Devonian rifting of the Burma Terrane.
Acknowledgment: I would like to express my sincere thanks to Gérard Dupré for providing the entire manuscript.
Prendini L, Xuan Q, Du S, Wang C, Ehrenthal VL, Loria SF. Phylogeny and divergence time estimation of relict Asian scorpion family suggests Early Cretaceous connections between Burma Terrane and Eurasia, and corrects placement of Chinese taxon. Am Mouse Novit. 2026;4051:1-55. Published on February 27, 2026.
