Monday, 17 December 2012

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

Monday, 10 December 2012

Specimen recuration or 'how to fix a broken beetle'

We recently had an enquiry asking for advice on how to fix an entomological display specimen and after some discussion, it was decided that it would be best if the specimen be bought into the collection to be professionally repaired. The specimen was that of a scarab beetle, Chalcosoma atlas (Rhinoceros or Atlas beetle) a relatively large species found in South-east Asia. 
As specimen repair is something that we have to undertake on almost a daily basis and one of the seemingly more baffling aspects of our job (not many people get to say that they glue insects back together for a living after all) we thought it might be interesting to show something of the hands on side of our work. We undertake repairs on a whole variety of dried insects and arachnids, many of which are of historical value. Damage can occur either through pest or mechanical action or from initial poor specimen preparation.

The first image shows the scarab as it was when it arrived. Along with the obvious destruction, there was also severe pest damage, caused by the Flour beetle, Tribolium castaneum. This meant that before any restoration could be done, the specimen needed to be frozen to kill any remaining pests. It was bagged up and frozen at -30°C for six days. Once it was un-bagged and removed from the frame, it was vacuumed thoroughly to remove all the dust and debris caused by the pests. A paint brush was used to gently clean the specimen. 

Insect, Coleoptera, Scarabaeidae, Chalcosome atlas, HEC, OUMNH, specimen repair
Pest damage has led to this specimen disarticulating in its display case

The restoration had to be done in-situ as the specimen was glued to the glass to with some heavy duty glue and could not be removed. 
The first stage of repair was to reattach the legs; there were two missing, one beneath the right wing and the right front leg, which was also missing part of its claw (these areas are highlighted in red on the image below). The glue we use to fix insects is of conservation grade and water-soluble; this means that it will not have a detrimental effect on the specimen; it does take longer to dry, but has the benefit of drying clear.


Insect, Coleoptera, Scarabaeidae, Chalcosome atlas, HEC, OUMNH, specimen repair
Areas ringed in red show where repairs have been undertaken on the specimens legs

Once the legs were secure, the head was attached. Foam was required to form a ledge to raise the head to the correct angle; pins were then used to hold it in place for the two hours it took for the glue to dry. The image below, top shows the positioning required. The final stage was the re-attachment of the elytra (front wings). A similar method was used as for the head, but this time towers of white tack were also needed along with the pins to form full support (below, bottom); because the area of attachment was so small, the weight of the elytra needed to be completely supported while the glue dried.


Insect, Coleoptera, Scarabaeidae, Chalcosome atlas, HEC, OUMNH, specimen repair
Head propped on plastazote block to obtain correct angle
Insect, Coleoptera, Scarabaeidae, Chalcosome atlas, HEC, OUMNH, specimen repair
Wings held in posistion with stacks of white tack



Once the glue had dried clear in all the areas, the specimen was finished and ready to be reframed, as seen below- or not as the case may be as the aim of all repair is to do it in such a way that it should be almost impossible to tell that it has been fixed.

Insect, Coleoptera, Scarabaeidae, Chalcosome atlas, HEC, OUMNH, specimen repair
The final appearance of the specimen once it had been repaired



Tuesday, 4 December 2012

It's a home invasion!

Over the course of the year we get many enquiries from members of the general public asking us to 'name that bug'. Some of these enquiries are of insects that people have spotted whilst out and about in the town and surrounding countryside, a few are even of tropical species that people have photographed whilst on holiday. The majority however, come from people who have found something inside their homes and they might want to know what it eats or whether to worry about it being venomous but more often than not, people just want to know what it is. Often these insects have become objects of fascination and people want to learn about them but until they have a name it can be hard to find the information they want.

So that's where we come in. We provide a free identification service (entomology@oum.ox.ac.uk) for anyone who might have an insect related question, regardless of where they live. We have identified insects for people from places as far away as Australia or as close to home as the Chemistry Laboratory next door.
We always enjoy the challenge and are more than happy to supply people with on-line links or articles about the insect they have found.

In order to get your insect identified then we need one of two things- either a good photograph of the insect or the specimen itself, alive or dead.
If you have the capability to take a good photograph then this can be an excellent resource. Preferably the photograph would be a dorsal shot (the top side of the insect) with good natural lighting. Make sure that all the legs and antennae are in focus and that there is some frame of reference for size. Adding a ruler or coin to the picture will do nicely. Sometimes it might take two or three photos to show the different parts of the insect, especially if it is a bit wriggly.

As many insects are very small and thus difficult to photograph well another option is to send us the specimen. Specimens can be dropped off in the museum in person where we may be able to give you an on the spot identification or they can be posted to us. When posting a specimen you want to pack it into something sturdy such as an old film canister with a bit of tissue in it to stop the insect from rattling about. This works for specimens whether they are dead or alive.

Regardless of whether you send us a photograph or the insect itself there is some extra information that is always useful to us. Firstly, your contact details so that we can let you know what it is that you have found. Secondly, a bit of information about where and when it was found as even a small piece of extra detail can help when identifying something.
For example, there are a few red beetles in the UK such as the Cardinal Beetle, Pyrochora serraticornis or the Poplar Leaf Beetle, Chrysomela populi but if you added in that you had found it on a lily plant then we would know before we had even seen it that it was mostly likely going to be the Scarlet Lily Beetle, Lilioceris lilii which is a pest of Lilium, Cardiocrinum and Fritillaria (lilies and fritilaries). Incidentally, two fun facts: this species makes an audible squeak when you pick it up and the larvae disguise themselves from predators by covering themselves with their own excrement!


Here is an example of an insect that walked in to be identified today, a Pentatomid bug that goes by the name of Dolycoris baccarum or The Hairy Shield Bug. Even though the picture is slightly out of focus there is still enough detail in the photograph for us to be able to identify it.

Hemiptera, Pentatomidae, Dolycorris baccarum, Sheild bug, insect, identification
An adult Dolycorris baccarum or Hairy Shield Bug

This species can commonly be found in houses at this time of year as they seek out a warm, concealed spot in which to over winter. Other things to look out for include ladybird species such as Adalia 2-punctata, (the 2-spot Ladybird) and Harmonia axyridis (The Harlequin Ladybird) which like to hibernate around the edges of windows.


If you have any questions or would like us to identify an insect for you then please contact a curator using the following e-mail address: entomology@oum.ox.ac.uk