To me there is something thrilling and exotic about blind beetles. They’re the sort of things I expect to exist in guano-filled bat caves in the tropics, or deep underground in the limestone districts of the Mediterranean. But I’ve been finding one species in my back garden recently when lifting the spuds: the tiny bothriderid Anommatus duodecimstriatus. To be found by carefully inspecting the remains of the seed potatoes. The potatoes have many eyes but the beetles have none!
Although most likely to be encountered in old seed potatoes, it has apparently also been recorded ‘under elm wood’, under bark and from ivy. It is Nationally Scarce (Na) but I tend to think that anything that occurs in our perfectly ordinary garden must be common, even if it isn’t seen very often. There is another, even rarer (RDBK) species in the genus, Anommatus diecki, which is associated with subterranean dead wood.
Parabathyscia wollastoni (Leiodidae) is another splendidly-named blind beetle that I saw for the first time this year by suction-sampling in grassland surrounding Sutton Bingham Reservoir, Somerset. It has no conservation status – in other words, it is common – so maybe I just haven’t been looking properly for the last twenty years. Joy describes it as having a ‘very small eye’ but I can‘t see one. Like A. duodecimstriatus, it can sometimes be found in old seed potatoes. There is another blind leiodid on the British list, a species I have yet to see, Leptinus testaceus (on the left in this photo). It can be found in or near the nests of mice and bumblebees and is probably an ectoparasite on mice.
The weirdest blind beetle I have seen in Britain is Claviger testaceus, a pselaphine that inhabits ants’ nests. My sole encounter with this species was on the extremely steep, loose, chalk rubble of Culver Cliff on the south coast of the Isle of Wight in a Lasius ?niger? nest. I’d love to see more of them and also to see the really rare (RDB1) Claviger longicornis but given that I must have looked at hundreds of ants’ nests under rocks and only once found a Claviger, I suspect it could be a long time before I see another.
With the help of Steve Bolchover, Roger Booth, Michael Darby, Tony Drane and David Murray I think there are six other blind beetles on the British list, in addition to the six already mentioned above, though there may be more. The subterranean weevil Ferreria marqueti (Raymondionymidae) was added to the British list from Kew Gardens by Alex Williams in 1968. More recently John Owen has established that a good way to find it is by setting subterranean traps at the roots of exotic conifers in suburban gardens in SW London. Owen’s study recorded 193 individuals, with records from 10 out of 12 gardens studied. The same study found 162 specimens of the blind subterranean colydiid beetle Langelandia anophthalma, from four of the gardens. Langelandia is a Rare (RDB3) species, associated with a range of decaying underground plant material: it has been found around decaying tree roots but also in old seed potatoes. There are also three species of Ptinella (Ptiliidae) that can occur in either blind or eyed forms: P. errabunda, P. aptera and P. taylorae.I’ve seen errabunda and aptera on several occasions, either under bark or (aptera) in a woodchip pile. Finally, there is the peculiar salpingid Aglenus brunneus which I have only found once, by sieving straw on the floor of a barn. This seems to be its typical habitat, especially where there is mouldy corn mixed in with the debris.
We may one day get another if the beaver reintroductions bring Beaver Beetle Platypsyllus castoris (another leiodid) with them. But the beavers have been combed before release into the wild, and so far, no Beaver Beetles. Shame! Bizarre-looking things (on the right in this photo).
Although they lack eyes it is probably not fair to describe these beetles as blind – they probably have enough photosensitivity to be able to shy away from the light and burrow into the dark.
Thanks once again to Oxford University Museum of Natural History for use of the digital photo-montage kit.
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