Hoverfly - Striped-backed Glimmer (Riponnesia splendens)

Striped-backed Glimmer (Riponnesia splendens) Size: 5.5-7mm Flight: May-Sep

Species of the week – 13^th Sept

This is not a common species and would seem to be localised, with only 1479 records listed on NBN as of September 2025

https://species.nbnatlas.org/species/NBNSYS0100005170#overview

This species is in a genus all by itself within the U.K, having previously been listed under the genus Orthonevra due to its morphological likeness. Prior to this it was classified in 1822 under the genus Chrysogaster, again a not too dissimilar morphological grouping.

There are four other species to this genus listed in Europe:  R.insignis and longicornis (Turkey) and in southern Europe R.daccordii and morini.

Its larva develops in wet mud in shallow water, adults are often seen visiting umbellifers particularly meadowsweet around marshes, meadows and woodland rides/clearings,

I found this specimen at Old Moor RSPB on fennel. Its distribution is more southerly, but it could be spreading north due to climate change.

Naming:

Besides Striped-backed glimmer other names often given are ‘Green glimmer’ due to its metallic look. This is because the thorax and margins of the abdomen glimmer green or copperish, against a matt-black abdomen.

Easily Confused with:

The soldierfly known commonly as the Broad Centurion (Chloromyia formosa) so checking the wings for the Vena Spuria and false wing margin will confirm this.

What to look for:

I look for the distinctive transverse grooves on top of the head between the eyes of females. If it is a male then the two longitudinal markings on the thorax, which look a little like Stripe-backed fleckwing (Dasysyrphus albostriatus) but less pronounced and without the yellow abdominal markings.

The antennae are black and slightly orange below, eyes green-brown, and the stigma cloudy.

They are slightly larger than species of Orthonerva, Lejogaster, and Melanogaster which they are often confused with, but in my experience, it is hard to judge sizes especially if it is a lone specimen.

Features not obvious in the field:

Its face has a broad dusted band below the antennae, as compared with those of the Orthonevra genus which have a narrow band. It also lacks a facial tubercle which is a characteristic seen in its close relatives.

There are bristles on the stem vein of the wing, and the upper cross vein is not strongly recurrent.

Further reading:

Maibach et all. (1994) Limites generiques et caacteristiques taxonomiques de plusieurs genres de la tribu Ann.Soc.ent (in French) – This is the article that splits the genus Ripponesia from Orthonevra.