Issidae are small insects generally with a stocky body, as the wings mainly develop in width. Basic body coloration is not striking, usually shows brownish colors. The head has two ocelli. The forewings have strong pronounced ribs. They wrap the abdomen when the insect is at rest. The family originally included approximately 1000 species with 215 genera, but the systematics of Issidae remains uncertain, with many of the subfamilies having been recently removed to separate families, includingCaliscelidae.Nogodinidae, andTropiduchidae.
In 2013, scientists described a biologically unique set of mechanical gears in anIssusnymph, though identical structures are known in most planthoppers, and were known for decades[1] before the function of the gears was discovered[2][3]
The family Issidae was once large and included many groups which are now treated in other families or as families themselves. These groups include theCaliscelidae,Nogodinidae, andTropiduchidae (e.g., subfamilies Tonginae and Trienopinae). Around 2003, there was a view in favour of a single subfamilyIssinae, but the current consensus is placement in four (as below). TheCatalogue of Life[4] lists genera in five tribesIssini,Parahiraciini,Hemisphaeriini andThioniini. The tribe Colpopterini[5] have now been placed in familyNogodinidaeMelichar, 1898 having been raised to a subfamily.[6] The oldest fossil of the group isCubicostissus of the PaleoceneMenat Formation of France, belonging to the tribe Hysteropterini, molecular clock calibrations suggest a diversification during the Upper Cretaceous.[7]
The monotypic subfamily contains the sole tribeIssiniSpinola, 1839[9] and has a widespread distribution in Europe, the Middle East and temperate Asia.[10] There are currently ten genera:
Uphodato Szwedo 2019,Krundia Szwedo 2019 andBreukoscelis Szwedo 2019 from theBembridge Marls, England dating Eocene (Priabonian) were considered members of this family upon description, however, other authors have found assignation to Issidae dubious.[7]
^Spinola M. 1839 - Essai sur les Fulgorelles, sous-tribu de la tribu des Cicadaires, ordre des Rhyngotes. Annales de la Société Entomologique de France. Paris 8: 133-337.
W. E. Holzinger, I. Kammerlander, H. Nickel: The Auchenorrhyncha of Central Europe - Die Zikaden Mitteleuropas. Volume 1: Fulgoromorpha, Cicadomorpha excl. Cicadellidae. - Brill, Leiden 2003
Stephen W. Wilson – Keys to the families of Fulgoromorpha with emphasis on planthoppers of potential importance in the Southern United States -Florida Entomologist 88(4)Fcla.edu
