Metadelphax propinqua (Fallén)
Caution
Many of the insects depicted on these pages are outwardly similar and you should not use photographs as the sole means of identification. These pages form part of a scientific key which will assist a trained entomologist to identify the species accurately.
Metadelphax propinqua (Fieber, 1866)
Common Name: none known
Subfamily/Tribe: Delphacinae: Delphacini
Distribution: Widespread globally, Metadelphax propinqua is found on every continent except Antarctica. Within Australia it has been recorded from the NT, Qld (Brisbane), and NSW (Narrabri) (Fennah 1965; Bellis unpublished data).
Economic Status: Metadelphax propinqua feeds on a number of species of Poaceae, including sugarcane, barley, maize and rice (Wilson & O’Brien 1987). It is a known vector of Cynodon chlorotic streak nucleorhabdovirus, Maize rough dwarf virus, and Barley yellow striate mosaic cytorhabdovirus (Wilson & O’Brien 1987; Wilson 2005; Bartlett 2018). Cynodon chlorotic streak nucleorhabdovirus and Maize rough dwarf virus are not present in Australia (Plant Health Australia 2011), whereas a strain of Barley yellow striate mosaic cytorhabdovirus has been recorded here (see Milne & Conte 1985)
Notes: There are five species of Metadelphax globally, but M. propinqua is the only representative within Australia. The status of Metadelphax is in doubt, with Gonzon & Bartlett (2008) suggesting it may be better placed as a subgenus of Toya. Indeed, species of Metadelphax are externally indistinguishable from some species of Toya, of which there are five species in Australia (Bellis & Donaldson unpublished data). Species within both these genera can only be identified through examining the male genitalia. Further, individuals of M. propinqua can be brachypterous (reduced wings) or macropterous (fully winged).
