Papilionid Caterpillars

Description:

The 1st. and 2nd. photos above show larvae of Papilio demoleus demoleus Linnaeus 1758 (Papilionidae; Papilioninae; Papilionini). The 3rd. and 4th. show larvae of Menelaides polytes ledebouria Eschscholtz 1821 (Papilionidae; Papilioninae; Papilionini). The purpose of this spotting, as you will have guessed by now, is to show the "Osmeterium". When I first became interested in the biodiversity of the Philippines, I had never heard of an Osmeterium and was taken by surprise when I first saw one. I realise that many P.N. spotters, especially those who are butterfly enthusiasts, will know all about Osmeteria, but for the benefit of those who have not yet come across them, this might help. Wikipedia gives a really good scientific description, but if I paraphrase a little of it in simple terms, it might be useful. Basically, the Osmeterium is an organ (inside the caterpillar's head) which it can push out as a defence mechanism if it feels threatened. It is reddish and looks a bit like a snakes tongue and gives off an odour which is unpleasant to many predators and can actually kill some ants and mantids. However, it is harmless to humans and, to us it smells strongly of lime and pineapple. So, nothing to fear if you see one. For a full scientific explanation with plenty of detail, visit https://en.wikipedia.org/wiki/Osmeterium.... I should just add that every Papilionid larva has an Osmeterium.

Habitat:

All of the larvae shown here were spotted on Citrus trees in our front garden.

Notes:

Project Noah requires the date of a spotting to be shown and, obviously this would normally be a single date. However, I would have found it pretty much impossible to have the opportunity to take all of these photos on one day. So to avoid any misrepresentation, the dates of my pictures (in the order they appear above) are: 5 August, 2016, 22 August, 2016, 13 July, 2016 and 28 July, 2016.