Neoascia tenur

For terms, see Morphology of Diptera
Wing length 3-5 ·25 mm. Tibiae 1 yellow with the dark ring. Metatarsae 1 yellow with the dark patch, other segments of tarsi 1 yellowish. Females: abdomen not as broad as N. meticulosa. The male genitalia are figured by Barkemeyer & Claussen (1986) ^[8] Larvae and puparia described and figured by Maibach and Goeldlin (1993) .^[9] See references for determination.^{[10] [11] [12][13]}

The male genitalia are illustrated by Barkemeyer and Claussen (1986) ^[14]

Palearctic Fennoscandia South to Iberia and the Mediterranean basin. Ireland east through Europe into Turkey and to European parts of Russia and on to Siberia. ^[7][15]

Habitat: Wetlands, flushes and streams in blanket bog, raised bogs, fen, wet grassland, pond and lake margins and along brooks.^[16] Flowers visited include Caltha, Cicuta virosa, Filipendula ulmaria, Potentilla erecta, Ranunculus, Salix repens. ^[17] The flight period is April to September. The larva is sub-aquatic within stem sheaths of Typha and other water plants.