Sunday, 10 August 2008

Almost identical non-twins.

It wasn't my intention to put any moth pictures on the blog today. It's harvest time and that normally brings lots of photo opportunities, and I was on my way out this afternoon, to take some, when I met a young man in a hurry who came round a blind bend rather too fast and despite my attempts to put my car out of harms way in the hedge made considerable contact with me.

Mostly at this time of year one has to be careful of this sort of monster trundling along the roads, but since no one was hurt all should be sorted out OK. I will have to wait to take this years crop of pictures of hay bales of various description.

One of the fascinations of natural history is species pairs, whether it is two species of birds, Goldcrest and Firecrest for instance, two plants, Southern and Northern Marsh Orchids or in this case two moths, it is always amazing how evolution has produced two such similar organisms.

Swallow and Lesser Swallow Prominent moths are one such pair. Here in my garden I catch quite a lot of Swallow Prominents but few Lessers, while down in Kingsdown, Nigel Jarman catches loads of Lesser Swallow Prominents but not many Swallow Prominents. Last night I had two sitting nest to each other in the trap. The Lesser Swallow Prominent shows a single, obvious white wedge or triangle, on the trailing edge of the wing, visible top left centre of the moth in the picture.

The Swallow Prominent has two much thinner less obvious lines, hardly triangles in the same place. There is very little difference in size, but they are distinct species, as examination of their essentially private parts under a microscope would show.

Another nice little catch last night was this Toadflax Brocade. It is a reminder of how close we are to the sea, as the book says its preferred habitat is vegetated shingle beaches. It is still confined to only a few areas. This is the sixth one to visit here, so they are either migrants or wanderers from the beach at Kingsdown where there is a colony.

This little Tortrix moth, Cydia amplana, is a rare immigrant and this is the first I've caught. The first for this area was caught by Nigel Jarman at Kingsdown.

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