Monday, 2 May 2011

All new moths

The good weather has encouraged a number of moths to emerge in the past few days, many of them much earlier than we would usually expect to see them. Moths are generally tied to specific plants or plant families, so the basic rule is: the more native plant species you have in your area, then the wider will be the variety of species of moth you will be able to find.

My first new moth for today comes with a little bit of controversy: many moths are bivoltine - they have two generations per year. This is complicated by the fact that some species have two generations in southern areas, but only one generation in northern areas. The Engrailed moth has tentatively been divided into two species - Engrailed and Small Engrailed, largely based around the number of generations in different areas. The picture is currently far from clear, and perhaps we're just part way through the evolution of a new species. Until the matter is resolved, we have to refer to these specimens as Engrailed/Small Engrailed.

Engrailed/ Small Engrailed

Both species feed on a wide range of trees and shrubs.

The Dark-barred Twin-spot Carpet can be separated from confusion species by the 'notch' in the front edge of the dark band on the wing. The larvae feed on herbaceous plants such as Dock. 
Dark-barred Twin-spot Carpet

Nut-tree Tussock feeds on broad-leaved trees as a larva:
Nut-tree Tussock
Everyone knows that Swallows fly from Africa to nest here every year. It's fairly well-known that butterflies such as the Painted Lady and Red Admiral can make a similar journey. What is much less well known is that we have micromoths that are also migrant. The Diamondback moth is only about 10mm long, but if the wind is right, then we can find them in good numbers in favourable years. They are too delicate to survive our cold winters, so we can be sure that any we find have made the journey from the Mediterranean area:

Diamondback moth 
I'm waiting for confirmation of the identity of this moth that came to light last night, but I'm fairly confident that it's Glaucus Shears:
Glaucus Shears - tentative identification

This moth is a good example of the effect of habitat: they are only found very near their host plants; Heathers, Bilberry and other heath plants. Also suspected to be migrant.

All of these moths are new to me, so my Species Index has suddenly leapt to 1393 species.


the mountain fox said...

Fascinating! Was just thinking about putting up a species list on my blog too! It's going to be a while before it reaches 1393 though!

The Weaver of Grass said...

Incredible number of moths that Stuart. I have just walked round our local Arboretum. There was a laburnum tree in full flower and one branch had three or four flowers on the end which were pink instead of yellow. Can you account for that?

Stuart said...

Weaver: your mystery Laburnum sounds like Laburnocytisus 'Adamii', which is a chimaera plant made from two species: Laburnum anagyroides, and a broom, Chamaecytisus purpureus. Originally a graft, the plant can only be propagated by cloning. More details on:'Adamii'

Mountain Fox: the 1393 species are the result of 8 years of recording on my local patch. I am very lucky to live in an area which includes deciduous woodland, bog, heath, hedgerow, riverside and ponds. This wide range of habitats in a relatively small area leads to a much greater biodiversity than I would normally expect to find. In wildlife, habitat is everything.