Recognition

Thanks to Dave General for pointing me in the direction of the Ants of the Philippines website, which I wasn't aware of. This is despite me thinking of visiting the country to collect ants and at the same time visiting a (non-myrmecologist) Filipino friend.

Ah well, I can't know everything, and experiences teaches me that I know very little.

This has also led to the discovery that I'm listed on a respectable blog like The Ant Room... which is nice.

Near heart attack

Okay, so probably everyone's seen this now and I've arrived late at the party, but it reduces me to tears every time I watch it.

It seems like more evidence that panda conservation is a waste of money - they're obviously not fit for survival!

Tapinoma ambiguum

Update 19th April 2008: This specimen was not correctly identified, as it is actually T. simrothi subsp. festae. However, the images on AntWeb are still incorrectly labelled as T. ambiguum, so perhaps I shouldn't feel too bad!


I've been fairly quiet recently because I've been busy trying to identify ant specimens, rather than writing about them. However, this one deserves a special mention.

Back in September I attended a BWARS workshop on two pairs of closely related species. None of the species are especially common in the UK and one from each pair is more common than the other.

We were able to find two specimens of Stenamma westwoodii, a near endemic in the UK (it's also found in Belgium), to compare with S. debile. However, between all of us and the collection at Oxford University Museum we could not produce a single Tapinoma ambiguum to compare with T. erraticum - or at least if we did no one told me! I was rather disappointed, as I had seen T. erraticum many times from Europe, but had not once seen T. ambiguum.

A few weeks ago I agreed to look at some specimens collected by David M. King. One of the specimens from Turkey is a very obvious T. ambiguum, so I have now seen it! The attached photomontage [removed] shows the cloacal aperture, low petiole, four dorsally visible tergites on the gaster and shallow clypeal notch that characterises the species.

This appears to be the only reliably identified photograph of this species online, as the images named T. ambiguum on AntWeb are clearly T. erraticum. The depth of the clypeal notch on the AntWeb specimens is equal to their width, whereas in T. ambiguum the depth should be less than the width.

Camponotus flavomarginatus

Camponotus flavomarginatus is the only member of the subgenus Myrmosericus collected in The Gambia that provided no great difficulty to identify. It is distinguished by the smoothly rounded propodeum and the arrangement of the dense pubescence on the gaster, which is laid more or less straight back, rather than distinctly converging at the midline (compare with C. rufoglaucus subsp. controversus and C. cosmicus).

C. flavomarginatus is very widely distributed, being found from South Africa north to Saudi Arabia and west to Guinea. In The Gambia it was collected in the coastal areas (Kololi and Bijilo Forest Park), but did not appear to be present on Jinack Island. It was generally found as single workers running on the ground, though at Bijilo Forest Park it was collected from a palm frond.

Camponotus rufoglaucus subsp. controversus

Camponotus rufoglaucus subsp. controversus is the second of the three species of Myrmosericus found in The Gambia. This is another ant that was by no means easy to identify.

It is clearly C. rufoglaucus because of the arrangement of the pubescence on the gaster, the smoothly rounded propodeum and the very compressed tibia (visible in the bottom picture). However, C. rufoglaucus sens. str. is an Indian species; in Africa there are at least seven subspecies. The two Gambian collections were identified as C. rufoglaucus subsp. controversus from type descriptions, since the tibia are clearly compressed, the head and mesosoma are entirely red, and the legs are black.

I also found some specimens labelled as C. rufoglaucus subsp. controversus in the London Natural History Museum, though not types and majors only. These specimens had a greater number of setae all over and pubescence on the gaster that was not as divergent, but identical colouration. However, as these were not types and the pubescence on the gaster was different from the type description I'm not convinced that they were identified accurately.

I also checked some of the many C. rufoglaucus sens. str. specimens in the museum collection. These were clearly not the same as my specimens (the Indian and Ugandan specimens in the museum collection were also not the same as each other), and again had less divergent pubescence on the gaster.

C. rufoglaucus subsp. controversus had been previously recorded from Tanzania, Zaire and Angola, so these Gambian collections represent a north-west range extension. They were collected only in Kololi as single workers on the sandy ground; no colonies were located.

Camponotus olivieri

Camponotus olivieri is a widespread species in Africa, ranging from South Africa north to Sudan and west to Ghana. However, it is made up of a great many subspecies that probably deserve species status, so the situation may be rather more complicated than it seems at first.

Two subspecies of C. olivieri were collected in The Gambia: lemma and delagoensis. They differ quite markedly in pubescence and also, to a lesser extent, morphology. What I think provides some evidence that they deserve separate status is that they were both found at one site.

C. olivieri subsp. lemma was found in two locations: Abuko National Park, Lamin and Bijilo Forest Park, Kololi. In both cases it was found only on the ground. It can be distinguished from other species of C. olivieri by the rust colour at the base of the antennal scapes and the gaster, which is uniformly shiny, sparsely pubescent but still more densely pubescent than the mesosoma and has erect hairs that are thicker than the pubescence.

C. olivieri subsp. delagoensis was found at Abuko National Park, on a tree. It is similar to subsp. lemma, but has denser, yellow pubescence, especially on the gaster.

Both ants have been recorded only rarely, possibly due to the fact that they are regarded as subspecies and so have been more frequently recorded at species level. C. olivieri subsp. lemma had been recorded in Angola, Tanzania and former Zaire. C. olivieri subsp. delagoensis was only known from the type location at Delagoa Bay in Mozambique. This makes these Gambian records an extension of the known range of the species and both subspecies, especially large in the case of subsp. delagoensis.

These have both been compared with the type specimens from the Muséum d'histoire naturelle, Genève and the Naturhistorisches Museum Basel. This allowed me to confirm C. olivieri subsp. delagoenisis.

The syntypes of C. olivieri subsp. lemma are rather variably hairy, so much so that I wondered if Forel had mounted specimens from different colonies on the same pins. The main difference between these and my specimens was that most of the types were much less hairy, though one was similar to mine. It could be that the specimens have lost some of their pilosity. Regardless, I feel I need to do some more work to confirm that there is nothing closer.

Unusual petiole shape in Lasius umbratus

In my last post I mentioned photographs of a queen ant that were posted to the BWARS discussion group. I asked the collector to send the specimen so that it could be identified properly and I've now had the opportunity to look at it.

It is a Lasius umbratus queen, which was correctly guessed by Andrew Jarman (my guess wasn't even in the right genus). The L. umbratus group is difficult, so I worked the specimen through a number of keys, but it was the head measurements in Seifert (1988) that gave the least ambiguous answer.

The petiole, the interesting thing about this specimen, is as unusual as it appeared in the original photographs taken by Claes-Göran Magnusson. So as to give a clearer impression I've taken some images of my own. The petiole in L. umbratus usually is emarginate, but it can be seen from these photographs that the emargination is much deeper, almost to the level of the anterior peduncle.