Four new species underline the hidden diversity and long-range dispersal in Deltoxenos Benda, Pohl, Nakase, Beutel & Straka (Strepsiptera, Xenidae)

Four new species of Strepsiptera from the genus Deltoxenos Benda, Pohl, Nakase, Beutel & Straka (Xenidae) are described based on the female cephalothoraces. These include the first Deltoxenos species from the Indomalayan and Australasian regions. New host species and genera for Xenidae – Phimenes solomonis (Vecht, 1959) and Pareumenes quadrispinosus (Saussure, 1855) – are recorded as strepsipteran hosts for the first time. Diagnoses and descriptions of female cephalothoraces are presented for all four newly described species of Deltoxenos , with brief diagnoses for Deltoxenos bidentatus Pasteels, 1950 and Deltoxenos rueppelli Kinzelbach, 1971. The known distribution of D. bidentatus and D. rueppelli are significantly expanded, and a notably broader host range documented for the latter. Diagnostic characters and geographic distribution are discussed in the context of a recent long-range dispersal event from Afrotropics to the Australasian region.