A new record for a little red Lygaeid

Arocatus longiceps is in the insect order Hemiptera, commonly called ‘true bugs’ and is part of the family called Lygaeidae often referred to as seed bugs, due to their feeding behaviour on plant seeds. This species is not native to the UK and was first discovered in Britain during 2007 on plane trees in the grounds of the Natural History Museum, London. This appearance made the bug quite famous; it even featured on the BBC News in 2008 as a new, apparently unidentifiable species.

Originally this species was determined as Arocatus roselii, however specialist researchers in seed bugs were consulted and the bug was finally identified as Arocatus longiceps an eastern Mediterranean species which has been spreading across Europe over the last few decades.

The species has mainly been recorded in the London area; but on the 30th November 2012 two specimens were found in the basement rooms at the Museum. This is a new record for Oxfordshire (Flanagan & Ryan, personal communication) and is probably the most Northerly record so far.

Hemiptera, Lygaeidae, Arocatus longiceps, true bugHemiptera, Lygaeidae, Arocatus longiceps, true bug
Photographs of the Arocatus longiceps taken using the auto-montage system
This bug is commonly found across Europe, and in October Amoret saw quite a few during a visit to Prague. The host plant is the plane tree; when the specimens were found in the museum, it prompted us to see whether there were more. As the photos below show, upon searching the plane trees outside the museum, we found an abundance of this bug.
Hemiptera, Lygaeidae, Arocatus longiceps, true bug, entomology, field

Chris Jarvis of the Education Department uses his detective skills to find the bug.

Hemiptera, Lygaeidae, Arocatus longiceps, true bug, field entomology

A large number of Arocatus longiceps were found beneath the bark. They overwinter as adults in clusters.


Rediscovered: Meloe mediterraneus

A species of Oil Beetle, Meloe mediterraneus, which was previously thought to be extinct in the UK, has been rediscovered as part of the on-going Oil Beetle conservation project being run by Buglife.

Coleoptera, Meloidae, beetle, Meloe mediterraneus
Female Meloe mediterraneus. Photograph courtesy of John Walters.

The beetles were found at Bolt Head, a National Trust site in South Devon by a local naturalist who was carrying out a study for the Oil Beetle conservation project. The discovery was confirmed by Darren Mann who is a specialist in British Oil Beetles. It is the first record for this species in over 100 years and the first ever for Southwest England. It is currently the only site that this species has been found at but it is hoped that with further survey work more populations can be found in other areas of the county.

Prior to its rediscovery, the Mediterranean Oil Beetle was only known to have ever existed in the east of the country- in Essex and Kent. The beetle was last sighted in Kent in 1906 and was thought to be extinct in the UK until rediscovered this year.

One reason for Meloe mediterraneus remaining undiscovered was that the specimens were mistaken for the similar looking Rugged Oil Beetle, Meloe rugosus (previously blogged about by us here). The adult Mediterranean Oil Beetle is slightly larger than the Rugged Oil Beetle, and has a larger thorax. The Rugged Oil Beetle also has a crease down the centre of the thorax that is absent in the Mediterranean Oil Beetle.

Coleoptera, Meloidae, beetles, rugosus, mediterraneus, Meloe, British
Photograph to illustrate the differences between Meloe rugosus (left) and Meloe mediterraneus. Note the groove on the thorax of Meloe rugosus. Photograph courtesy of John Walters.

The triungulins (larvae) are possibly even more distinctive, with those of Meloe mediterraneus being entirely orange whilst those of Meloe rugosus have an obvious dark head.

Coleoptera, Meloidae, triungulins, larvae
                    Triungulin of Meloe rugosus (left) and Meloe mediterraneus (right).                   Photographs courtesy of John Walters.

In the news: Buglife, The Telegraph, WildlifeExtra
Mini guide to identifying Oil Beetles

Well, oil be

Now is the time of year to look out for the Rugged Oil Beetle Meloe mediterraneus and Oxfordshire can boast being one of this species hotspots in the UK. BugLife, the invertebrate conservation organisation, has been collating distribution data and promoting the conservation of the British oil beetles, all of which are in decline.

meloe rugosus, beetle, insect, OUMNH, HEC, meloidae
A female Rugged Oil Beetle, Meloe mediterraneus (Family Meloidae)
This group of insects has benefitted greatly from increased public awareness and with the help of newly recruited recorders we now have a much better understanding of the groups distribution across the UK.
Out of eight species of Oil beetle that have been recorded in the UK, four are thought to be extinct*. Of the remaining four species, two are relatively common: the Black Oil Beetle, Meloe proscarabaeus and the Violet Oil Beetle, Meloe violaceus. The other two, the Short-Necked Oil Beetle Meloe brevicollis and the Rugged Oil Beetle Meloe mediterraneus however are very rare.
All four species are important idicators of solitary bee populations as they are dependant on the bees for their own reproduction. Their lifecycle is pretty exciting really but is a little complicated at first glance. Here’s a simplified version to explain how the bees come into it all:
  1. A female oil beetle digs a burrow and fills it with hundered of eggs.
  2. The eggs hatch and the larvae emerge. These are called triungulia** and exhibit unique co-operative behaviour.
  3. The larvae gather on flower heads, forming living pyramids so as to enable them to hitch a lift on solitary bees visiting the flowers.
  4. The bee unwittingly transports its passengers and ultimately with a little luck, they end up in a female bees burrow. At which point they hop off and make themselves at home.
  5. The larvae eat the eggs of the bee, along with any stores of pollen and nectar.
  6. The larvae develops in the burrow, eventually emerging as an adult ready to look for a mate.

The short story? The more adult Meloe that are seen then the more bees there are.

Obviously it is more complicated than this and a whole wealth of further information can be found on the BugLife website, along with links to the recording scheme, identification guides and the Oil Beetle Conservation Project.
Staff at the HEC have been helping by identifying and providing data on specimens from Museums across the UK, as seen in this recent news article.
*within the UK; not worldwide.
** their name comes from the fact that they have three claws on each foot.