Systematics of Hadropygos n.g., Metadelphax Wagner and New World Toya Distant (Hemiptera: Delphacidae)

Abstract

New World members of the genera Toya Distant and Metadelphax Wagner are here revised and the genus Hadropygos n. g. described from South America. Generic limits are discussed, with particular comparison to Syndelphax Fennah. A key to treated genera and species is provided. The type species of Toya, T. attenuata Distant from Sri Lanka, is illustrated and discussed. Among the New World Toya, T. boxi (Muir) and T. venilia (Fennah) are retained in the genus; two species are transferred to Toya from Delphacodes Fieber, Toya idonea (Beamer) new comb. and T. nigra (Crawford) new comb., with Delphacodes axonopi Fennah placed as a new junior synonym of T. nigra. Three new species of New World Toya are described (T. goliai n. sp., T. dietrichi n. sp., and T. recurva n. sp.). Toya iaxartes (Fennah), described from a single specimen from St. Lucia, is here considered nomen dubium as it appears to have been described from a malformed or parasitized specimen. Metadelphax, restored as a genus by Ding (2006), consists of five species: M. propinqua (Fieber) (type species), M. argentinensis new comb., here transferred from Toya, M. pero, here transferred from Syndelphax, M. wetmorei (Muir and Giffard) new comb., here transferred from Delphacodes, plus M. dentata n. sp. Metadelphax bridwelli (Muir), transferred from Toya by Ding (2006), is returned to Toya. Hadropygos n. g., with the single species, H. rhombos n. sp., from the Neotropics bears comparable features to Toya and Metadelphax. Lectotype designations are made for Toya attenuata Distant and Delphax propinqua Fieber. Collectively, 3 genera are treated: Hadropygos n. g., with a single new species, Metadelphax with 5 species (1 new), and Toya with 7 New World species (3 new), excluding T. iaxartes as a nomen dubium.