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.