Lovely local longhorns

In Britain there are approaching 4,100 species of beetle and some of the most attractive and charismatic of these are the longhorns (Cerambycidae) known for their large size, bright patterns and long antennae. However, although some are strikingly coloured (such as the yellow and black Rutpela maculata), many are actually more sombre blacks and browns. One such species is the 'tawny longhorn' Paracorymbia fulva which I have found at three nearby locations during the last week or so, including my back garden.

Paracorymbia fulva

As you can see, it has yellow-brown elytra with black cut-off tips and is also otherwise black. It is very similar to male Anastrangalia sanguinolenta but has a pronotum wider than it is long and with rounded sides (in A. sanguinolenta the pronotum is more slender and less rounded), is 9-14mm long (excluding appendages) and is found in the adult stage between June and August. P. fulva is also interesting for a number of reasons.

Firstly, it is generally described as being associated with broadleaved woodland (e.g. Duff 2007a), but observations suggest that its habitats are more diverse than this. For example, my three recent sightings have been in a suburban garden, rough trackside vegetation and woodland edge while Michael Darby (in Wright 2011) reports that it is associated with chalk grassland in Wiltshire without any woodland or fallen timber.

Secondly, it is considered 'Rare' in the UK as it is listed as a Category 3 Red Data Book species (again e.g. Duff 2007a), but observations by mant recorders suggest that it is more common than this, even if still mainly associated with central and southern England. More widely, it is found across most of Europe, except the north and Turkey (Hoskovec & Rejzek 2007). Given that the northern limit is likely to be due to temperature, its expansion in the UK may be another example of a species spreading due to climate change.

Thirdly, no-one knows what it feeds on - or much else about it. This may seem surprising, and in some ways it is - as Martin Rejzec says in Wright (2011), P. fulva is one of the few remaining European species which has an unknown host plant, a larva that is completely undescribed, and an unknown life history. However, he goes on to explain that this may also be because, unlike most other longhorns, it does not develop in timber; instead it might do so in the underground parts of trees or shrubs, and the larvae may even be free-living in the soil, feeding for example on fungi. Whatever the case, it is clear that this is a species where there is clear opportunity for significant gains through targeted study and research, and as it is now more common in the UK, there may be a greater chance that this will happen.

If you are interested in longhorns in the UK, I strongly recommend acquiring a copy of Duff's excellent illustrated guide (2007, b) which will help you become familiar with this fascinating family of beetles.

A reminder that many longhorns are colourful, Rutpela maculata (sometimes placed in the genus Strangalia)

References

Duff, A. (2007a). Longhorn beetles: Part 1. British Wildlife 18(6): 406-414.
Duff, A. (2007b). Longhorn beetles: Part 2. British Wildlife 19(1): 35-43.
Hoskovec, M. & Rejzek, M.(2007). Paracorymbia fulva (De Geer, 1775). Cerambycidae. [accessed 19/07/2012].
Wright, R. (2011). Paracorymbia fulva - further information received. Beetle News 3(3): 6.