Post by saye on Nov 20, 2014 10:09:46 GMT -8
Back in June, I witnessed a certain behaviour of an Mimas tiliae larva, before pupation, and was left wondering just what was happening. Here's a description of the situation: before beginning any kind of wandering period, the caterpillar, rested on the underside of a leaf, opened its mandible widely and then began "to anoint" itself with some colourless substance that seemed to do nothing but add a degree of reflectiveness under (artificial white) light, it did so for the length of its body on one side, then another. This was repeated with more "intensity" and coupled with what seemed to be "biting" on the spiracle(s) at some points, with some occurrence, a small amount, of bubbling. Hours after this (less than eight), as is known of this family to happen, the larva had darkened and had begun its restless wandering period.
Into pupation (first as larva then as pupa) its body remained seemingly "wet", souped at the base even, for a few days (roughly six) until it appeared dry, or regular. The caterpillar was raised on a transparent hard plastic box with nothing but tilia leaves.
Are you in any way familiar with this occurrence? On the web, I've found but one place referencing the behaviour, with regards to Acherontia atropos, reading as follows: "Prior to pupation, the fully-grown larva darkens over a period of several hours, during which stage it anoints its whole body with 'saliva'; this appears to hasten the darkening process." I haven't found it mentioned in any other page/species (of the Western Palaearctic). Source.
What's that substance? What's its purpose? Is it shared by other sphingids? Is it seen in any other family of moths? Is there any literature on this?
Here are some photos:
-Larva-
(Less than eight hours later)
(About four days after)
-Pupa-
(about two days after, "drying")
Into pupation (first as larva then as pupa) its body remained seemingly "wet", souped at the base even, for a few days (roughly six) until it appeared dry, or regular. The caterpillar was raised on a transparent hard plastic box with nothing but tilia leaves.
Are you in any way familiar with this occurrence? On the web, I've found but one place referencing the behaviour, with regards to Acherontia atropos, reading as follows: "Prior to pupation, the fully-grown larva darkens over a period of several hours, during which stage it anoints its whole body with 'saliva'; this appears to hasten the darkening process." I haven't found it mentioned in any other page/species (of the Western Palaearctic). Source.
What's that substance? What's its purpose? Is it shared by other sphingids? Is it seen in any other family of moths? Is there any literature on this?
Here are some photos:
-Larva-
(Less than eight hours later)
(About four days after)
-Pupa-
(about two days after, "drying")