Small World Discoveries

HYMENOPTERA > SYMPHYTA > Tenthredinidae > Blennocampinae > Phymatocerini

An entirely black species that is invariably found on, or flying around, Yellow Flag (Iris pseudacorus) in wetland locations, but may also occasionally occur on cultivated irises. The larvae however, will only feed on irises in damp situations and/or close to water.

In normal wetland habitat, this sawfly is unlikely to be confused, but it is very similar to Phymatocera aterrima, which feeds on Solomon's Seal (Polygonatum sp.). If in doubt, the two species can be distinguished by the comparative length of the antennae. In Rhadinoceraea micans, they're about twice as long as the width of the head, sometimes slightly less in females, whereas in Phymatocera aterrima they're at least three times the width of the head and near enough as long as the body. Additionally, segment eight is about 2.5 times as long as wide in the former and five times in the latter.

Rhadinoceraea micans is a widespread species across most of England and Wales, but with very scattered, localised distribution. Of the two species, Phymatocera aterrima is by far the more common and more frequently recorded. In recent years there have only been a handful of confirmed sightings of Rhadinoceraea micans from either Dorset (VC9) or South Hampshire (VC11).

New species added, Feb.25 (v.1)