The two extinct species of Prosisyrina have been identified from adults that are preserved as inclusions in Taimyr amber.

The ambers of the peninsula occur in the upper levels of the Kheta Formation, which is exposed in a number of locations in the Taimyr region.

The hindwings have a unique character suite including a uniform midsection of the costal space, which is only also seen in Paleosysyra.

There are a series of trichosor setae preserved along the entire margin, with the basal section of the costal region.

The fossil shows a grouping of nine gonocoxites on the underside of the abdomen indicating it was a male, and the tip has a pair of large setae.

Based on the structure of the maxillary palps the species was placed with reservation in Prosisyrina.

The holotype of P. sukachevae is missing the rear segments of the abdomen, so it is possible P. sphinga may belong to a separate genus.