A Vapourer cocoon

13 Friday Oct 2023

Tags

British moths, moth cocoon, Orgyia antiqua, Vapourer, Vapourer cocoon, Vapourer larva

Here’s an intriguing find I made when doing a little leaf-turning during yesterday’s rather damp local meander – a hairy cocoon on willow.

231013 vapourer cocoon

From looking at the yellow and black hairs contained within the silk, I thought perhaps this might have been created by a Pale tussock moth. Fortunately, Andy, one of the moth-ers I follow on Twitter, recognised this cocoon and was able to correct my identification. This was, in fact, created by a Vapourer moth larva (Orgyia antiqua) – below is one I photographed a few years back (it had just shed its skin, the remnants of which can be seen to the left of the caterpillar).

231013 vapourer larva

I’ve not yet seen an adult Vapourer but they are a particularly interesting species, as the female is virtually wingless – you can read more and see some images on the UK Moths website. Andy also introduced me to the Lepiform e.V. website, which, though it is in German, can still be searched using a moth’s scientific name and has an excellent and comprehensive range of images for each species, including larval stages, cocoons, pupae, etc.

Leafmines: Bucculatrix ulmella

05 Monday Dec 2022

Posted by sconzani in insects, leaves, trees

≈ 2 Comments

Tags

British leafminers, Bucculatrix ulmella, cocoon on Oak leaf, leaf-mining moth, leafmining moth larvae, moth cocoon

This new-to-me species was the result of a recent session turning over Oak leaves to see what might be lurking beneath. I didn’t actually find the leafmines for this creature but rather, on adjacent trees, two empty cocoons – the tiny moths (pictured on the UK Moths website) that were metamorphosing inside had already hatched and flown (you can see part of the pupal case poking out of one cocoon). The ribbing on the cocoon points to this being one of Bucculatrix genus of moths and the fact that these were on Oak gives a positive identification of Bucculatrix ulmella (don’t be fooled by the specific name ulmella, which would appear to indicate the larvae feed on Elm – the species has apparently been misnamed).

221205 Bucculatrix ulmella

Wild word: cocoon

29 Wednesday Aug 2018

Posted by sconzani in insects, nature

≈ 5 Comments

Tags

#WildWords, 5-spot Burnet, 6-spot Burnet, British moths, Burnet moth cocoon, cocoon, Five-spot Burnet moth, moth cocoon, Six-spot Burnet moth, wild words

Cocoon: Noun; A silky case spun by the larvae of many insects for protection as pupae (Oxford Dictionary).
The cocoons in my photos are those of Burnet moths, both 5-spot (below left) and 6-spot (below right): you can’t tell the difference in the cocoons from the outside – I just know which moths were present in the locations where I took my photos.

After hatching from their eggs, the caterpillars/larvae of both moths feed on plants from the pea family; the 6-spot burnet is particularly partial to Common bird’s-foot trefoil, which is why I see a lot of these moths at Cosmeston.

When they’re ready to pupate, the caterpillars find themselves a suitable location, often high up on a sturdy grass stem (though I have seen them on other plants), and spin an oval-shaped cocoon. The cocoons pictured above are still occupied by caterpillars in the throes of metamorphosing into moths, a process which takes about two weeks.

These are the empty cocoons that remain once the adult moths have emerged (with the remains of the larvae’s pupae cases poking out the tops). The cocoons are quite sturdy: their yellowish-white papery structures often seem to last for a month or more after the adults have departed or even until the grasses themselves collapse with the coming of the wild winds and chilly days of autumn.