Ephydra riparia

Mathis, Wayne N. & Marinoni, Luciane, 2016, Revision of Ephydrini Zetterstedt (Diptera: Ephydridae) from the Americas south of the United States, Zootaxa 4116 (1), pp. 1-110 : 90

The riparia group

Species Included: Ephydra packardi Wirth.

Diagnosis. This species group is distinguished from others of the genus Ephydra by the following characters: General coloration more or less shiny, greenish to olive brown.

Thorax: Acrostichal setae in 4–5 irregular rows; tarsal claws generally not much over half length of tarsomere 5.

Abdomen: Aedeagus with a well developed, recurved basal process and with a wrinkled, membranous gland attached to anterior side of straight distal portion; gonite short, broad, and with a distinctive distal hook or pointed process; surstyli generally with a distinctive longitudinal carina.

Distribution. Old World. Northern Europe ( Sweden) to northern Africa (Canary Islands, Algeria) eastward through Russia and southern Asia ( Turkey, Iran) to Japan and China. New World. North America from Alaska (Fairbanks) to Nova Scotia (Baddeck), south to Baja California, northern Mexico, Louisiana, and North Carolina.

Remarks. In North America this species group comprises six species ( Wirth 1971), with only E. packardi being represented below the Mexican-United States border.