LARVAE OF HOMODES MIMICKING THE AGGRESSIVA OECOPHYLLA ANT IN SOUTHEAST ASIA|\VJS, COfylF. ZOOTj (LEPIDOPTERA, NOCTUIDAE) BY L. G. E. KALSHOVEN Blaricum, the Netherlands (With a coloured plate) llSRAkï AUG -7 1961 HARVARD Introduction. While collecting data from the files of the Institute for Plant-diseases at Bogor for my book on the pests of Indonesian crops, I found a note on a small Noctuid larva adorned with long filaments, which was considered to mimic the well-known aggressive Oecophylla ants. The note was written by AwiBOWO, sometime entomological assistant, who worked with the late Dr. S. Leefmans. There were coloured drawings and corresponding pen-drawings by a native artist in the same portfolio. The case described appeared too interesting to be left unpublished. However, I preferred to give more complete notes and references, and their collecting was only recently completed. The original note by AwiBOWO may be translated as follows. "It was during my field-work, which included investigations on ants, that I observed this peculiar insect. Dr. Leefmans had already informed me about its occurrence and how he had failed to breed the moth out of the single specimen he had found because it was parasitized. Dr. Leefmans had also lent me Shelford's book "A Naturalist in Borneo", in which a similar larva is mentioned and figured. All the larvae I had collected could be reared to moths. Specimens submitted to the British Museum of Natural History in London were identified as Homodes ftdva (Hamps.). "The larva in question mimics the ngrangrang ant, Oecophylla smaragdina, in a very striking manner. This is not shown by the drawing I had made. It is the appearance as a whole of the moving larva that causes the deception. On the host-plant the greenish body of the larva is camouflaged and only the brown-coloured parts are conspicuous. One's attention is first drawn to the insect by the appendages occurring on every segment of the body and which are kept in constant movement." [Here follows a passage which is in conformity with Shelford's description of the behaviour of a disturbed larva imitating the ant (see below).} "Furthermore it is noteworthy that these larvae were found on a mango tree which was visited by a multitude of ngrangrang ants. On some 200 other mango trees which were visited by species of ants other than Oecophylla — for instance the reddish gramang ants, Anaplolepis longipes — the larvae could not be found, though I was on the look-out for them. No connections between the ants and the larvae could be observed. The ants
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