Sympherobius pygmaeus

Four of the five British Sympherobius species have been found in Norfolk so far but none of them have been recorded more than half a dozen times up to 2025. However, as I've recorded 11 individuals covering all four species in unremarkable habitat here in North Elmham, I think they must be vastly under-recorded.

Most members of the genus tend to be rather dark brown and thus can recall the spongeflies (family Sisyridae). They can be distinguished from spongeflies by the presence of a recurrent humeral vein and the presence of forks in many of the veins along the front margin of the wing. From other genera of brown lacewings they are best differentiated by having fewer cross-veins in the hindwing (specifically, according to Plant (1997), none in the outer third of the hind wing OR no more than 4 altogether) - of course this is very hard to see on a live insect and unlikely to be evident from photos.

Like Sympherobius elegans, but unlike the other species in the genus, pygmaeus normally has only two branches to the radial sector of the forewing - the others have three (beware exceptions and check both wings). Unlike elegans (and also unlike the species that normally have three branches to the radial sector), the veins have alternating light and dark streaks and the thorax usually has a pale centre. There are also differences in the marbling of the wing membrane (see Plant for details). Identification of males is best confirmed by examining the tip of the abdomen (again, see Plant for diagrams).

This individual came to light and was Norfolk's third record.

female Sympherobius pygmaeus showing fore and hindwings, North Elmham (Norfolk, UK), 2nd June 2018

This individual had three branches to the radial sector of the right forewing but only two on its left forewing. The alternating light and dark bands on the forewing veins removed any doubt about the ID.

female Sympherobius pygmaeus showing fore and hindwings together and each forewing separately, North Elmham (Norfolk, UK), 13th June 2025

This individual had three branches to the radial sector of the right forewing but only two on its left forewing. The alternating light and dark bands on the forewing veins removed any doubt about the ID.

female Sympherobius pygmaeus showing side of abdomen, fore and hindwings together and each forewing separately, North Elmham (Norfolk, UK), 28th June 2025