Sunday, September 5, 2010

Why look like an ant?

Aint an ant

This morning, I found this ant-like chap on the wall. Anyone who does not look carefully might pass it off as an ant but anyone who knows a bit about the elbowed antennae of the ant family would know it was not. But what was it ?

It had a slender neck and the long rostrum suggestive of a Reduviid of which this could have been a nymph but how wrong can one be !

Turns out that this is Dulichius inflatus, a bug of the family Alydidae. And it is not a nymph, but an adult and it is (nearly) wingless!

"Some ant like forms are the most remarkable, and Mr Wroughton recently exhibited to the London Entomological Society an Indian Coreid which associates with the Ant Polyrhachis spiniger and is furnished with spines on the pronotum &c., resembling almost exactly those possessed by the Ant" - W L Distant, Rhynchota, Fauna of British India
Elbowed antennae ?

Looking up the entry in the Fauna of British India, one learns that it was described by W F Kirby. And a later specimen produced by R C Wroughton of the now largely defunct Bombay Natural History Society was described as Dulichius wroughtoni which became a junior synonym. Wroughton notes that the species is commonly found under rocks along with colonies of Polyrhachis spiniger (which seems to be synonym of P. lacteipennis) and that the spine structure varies widely across individuals !

A real Polyrhachis
What can one do after obtaining an identification from the few taxonomists left in India and researching the literature using the name? One could create a Wikipedia entry for a start and that makes one learn a little more too, sometimes it can be a bit of a consolation, especially when one finds out that W F Kirby, entomologist who described the species also thought it was a Reduviid ! A later amateur entomologist and physician from Finland, Bergroth who saw a specimen from Wroughton described the species as Dulichius wroughtoni and then came across Kirby's own description and decided that Kirby's had priority. However his note on Kirby is quite interesting, particularly as it comes from an amateur evaluating a self-professed expert at a museum of that time-period:

Mr. Kirby has had the kindness to send me a copy of his work on the Heteroptera and Homoptera of Ceylon (Journ. Linn. Soc. XXIV, pag. 72—176, with 3 plates). The author says in the introduetion, that he has thought his paper „would be rendering a real service to science". I think no serious hemipterist will be of the same opinion. As the author is assistant in the British Museum, one schould expect to find informations on the real systematic position of the many dubious Hemiptera deseribed from Ceylon by Walker, and it is therefore with great regret we find Mr. Kirby's work to be entirely in Walker's style and almost without any scientific value Mr. Kirby further says, that he will not create many new genera, 'until those already proposed have undergone a thorough and much-needed revision, which at present I have no time to "attempt".' It is to be hoped, that Mr. Kirby never will find time to a such revision, as it seems to be unknown to him, that the genera of Hemiptera have already undergone a thorough and most excellent revision by Stäl.


Postscript
Happened to visit one of the websites where photographers dump their pictures and found some rather excellent photos in the chaotic pile. Interestingly one from Bangalore seems to have been taken around the same time. Seems like the rains might be important factor for some aspect of their life cycle:

Photo 1
Photo 2

Also discovered a photograph of a Polyrhachis that I had taken - here sitting, perhaps in a defensive posture, on the spadix of a pink Anthurium - now added above.

1 comment:

  1. Amazing corelation! Great post! Just love those little creatures!

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