Monday, 11 January 2021

2020 Overview

With all the Covid restrictions, it was a very slow year for Diptera recording. The Northants Diptera Group did not meet at all during the year, although individual members did do some recording on their local patches and a little more widely when restrictions were relaxed.

As mentioned in the April 2020 blog, the dotted bee-fly Bombylius discolor extended its range  in Northants  but I have had no further reports since the ones for Sywell Reservoir and the Daventry area. 

With limited ability to get out, I worked through a lot of samples of flies taken in flight interception traps in 2018, and subsequently stored in alcohol. The traps had been set up primarily to find saproxylic beetles at Yardley Chase but I hoped some interesting saproxylic flies might also be present. Many of the specimens were in poor condition and not identifiable to species level and most of the ones I could identify were common species. However, one cranefly turned out to be Nationally Scarce - Rhipidia uniseriata. This is a saproxylic short-palped cranefly, family Limoniidae and this record is a county first. It was not in great condition but was clearly identifiable. The two attached photos show the key features.

Rhipidia uniseriata Female showing the serrate antennal segments, the male has pectinate segments



Rhipidia uniseriata showing the wing blotching with no blotches close to the body

Three locally scarce soldierflies were recorded during the year. Stratiomys singularior, the Flecked General, was swept at Yardley Chase (John Showers) and a second one was photographed at Summer Leys (Robin Gossage). This species is normally associated with saltmarsh but has been increasingly found inland in recent years. Stratiomys longicornis, the Long-horned General, was photographed  near Daventry by Beatrix Jackson. This is only the second record from Northants and is another species associated with coastal marshes.. The third locally scarce soldierfly was Odontomyia ornata, the Ornate Brigadier. One was found as a larva on Yardley Chase and reared to adulthood by Graham Warnes and another was photographed in the Nene Valley by Robin Gossage. It is associated with coastal grazing marshes with water-filled ditches. It is interesting that all three species have been associated with coastal areas and that all three are being increasingly found inland. It may be that climate warming is allowing the species to tolerate a wider range of habitats. 


Odontomyia ornata, the Ornate Brigadier (Graham Warnes)

Yardley Chase also provided a record of the long-bodied cranefly Diogma glabrata (Family Cylindrotomidae). The species breeds in moss in damp woodland. This is only the third record for Northants. Also at Yardley Chase a search of a recently cleared pond in October resulted in finding a colony of the short-palped cranefly (Family Limoniidae) Erioconopa diuturna. This is another county first. Although the species is widespread in Britain, its late flight season and tendency to prefer higher, wet pastureland, probably means it is overlooked.

So, despite the restrictions caused by the lock-down, the season was not a complete write-off. I look forward to the warmer months and easing of restrictions so that we can get out and continue to find and record interesting species throughout the county.