A review of the genus Psectrosema (Diptera: Cecidomyiidae), Old World pests of tamarix (Tamaricaceae), and description of three new species.
Psectrosema is reviewed, redefined, and placed within the tribe Oligotrophini (sensu stricto). The genus is a monophyletic group of 26 known species restricted to Tamarix (Tamaricaceae) from the Mediterranean region through Central Asia to China. A number of genera are reduced to synonyms of Psectrosema. The six poorly or incompletely known Mediterranean species of Psectrosema are reviewed. Three new species of Psectrosema from southern France are described that are candidates for biological control of tamarix or saltcedar [T. chinensis] in North America; these are P. nigrum sp. nov., P. album sp. nov. and P. acuticorne sp. nov., all collected in south-eastern France.