Genus Chionomus, Fennah 1971
Family Delphacidae
Subfamily Delphacinae
Tribe Delphacini
Distribution:
Two of these species are known from both North (Neotropics) and South America, one is only known from South America.
Type species (in original combination): Delphacodes havanae Muir and Giffard, 1924.
Recognized species
There are three recognized species in this genus:
Chionomus havanae (Muir and Giffard, 1924) -
USA: Florida, Puerto Rico; Cayman Is. (Grand Cayman); Cuba; Jamaica; Guatemala; Guyana; Trinidad; Venezuela; Panama
Chionomus balboae (Muir and Giffard, 1924) - USA: Florida, Puerto Rico; Brazil; Argentina; Mexico; Ecuador; Guyana; Paraguay; St. Lucia; Venezuela
Chionomus haywardi (Muir, 1929) - Argentina, Uruguay, Chile
Hosts:
Chionomus haywardi has been recorded on:
Oryza sativa L. (Rice)
Zea mays L. (Corn)
Triticum aestivum L. (Common Wheat)
Avena sativa L. (Common Oats)
Hordeum vulgare L. (Common Barley)
Names of plants from USDA PLANTS database.
Economic Importance: Chionomus haywardi is known to vector Mal Rio de Cuarto virus (MRCV) (Velazquez et al. 2003).
Recognition
When Fennah erected this genus in 1971 he utilized the meeting of the submedian carinae at the apex of the head, combined with a white pronotum and scutellum, reduced processes, and a dark spot near the clavus. Additionally, these species share a distinctly projecting armature of the diaphragm, parameres with the broad basal angles and a concave inner margin, and a tubular aedeagus.
Chionomus havanae

Chionomus havanae - brachypterous male

Chionomus havanae - macropterous male

Chionomus havanae - frons and pygofer
Chionomus balboae

Chionomus balboae - brachypterous male

Chionomus balboae - macropterous male

Chionomus balboae - frons
Molecular resources
Sequence data 28S and 18S are available on Genbank for Chionomus havanae. BOLD does not have any sequence data for this genus currently.
Selected References
Fennah, R. G. 1971. Fulgoroidea from the Cayman Islands and adjacent areas. Journal of Natural History 5(3): 299-342.
Muir F. A. G. & Giffard W. M. 1924. Studies in North American Delphacidae. Bulletin. Hawaiian Sugar Planters' Association Experiment Station. Division of Entomology. Honolulu 15: 1-53.
Muir, F. 1929. New and little known South American Delphacidae (Homoptera-Fulgoroidea) in the collection of the British Museum. Annals and Magazine Natural History 10 (3):75-85.
Velazquez, P. D., J. P. Arneodo, F. A. Guzman, L. R. Conci and G. A. Truol. 2003. Delphacodes haywardi Muir, a new natural vector of Mal de Rio Cuarto virus in Argentina. Journal of Phytopathology 151: 669-672.

