11 June 2020
9 June 2020 – Ah! Bistones
|Peppered Moth (Biston betularia)|
In 1845 this image might have helped the amateur enthusiast to identify the startlingly bright, black and white moth that had been observed or trapped by light, as a Peppered Moth. Both male (fig. 11) and female (fig. 12) are shown in the drawing which comes from British Moths and their Transformations by Humphreys and Westwood. Adjacent to the moths is a Yarrow (Achillea millefolia) which, although not listed as a food source, can be found in the hedgerows where the larvae feed on a wide variety of plants, shrubs and trees. The Yarrow is just coming into flower so the timing is appropriate .
The scientific name (Biston betularia) makes reference to the Gods of the Classics. Biston was the son of Mars (God of War) and Callirhoe (a fresh water nymph or naiad) and his name was given to the city he founded in Thrace. His followers were known as Bistones and their main preoccupation was a deep dedication to Bacchus – the God of wine and fertility. The second part of the binomial refers to the birch tree (betula) which Linnaeus cites as a food plant.
|Peppered Moth (Biston betularia)|
The drawing is certainly considered but a photograph (above) gives a better indication of the true beauty of this moth. Jackson Pollock could have learned a thing or two from the glorious abstract, ‘drip style’ decoration on the wings. A piece of egg carton is not the most appropriate background but I couldn’t remember if the Peppered Moth tends to fly when disturbed or can be repositioned easily. When I came back to it a little later, it had flown to seek sanctuary in the grasses.
|Ghost Moth (Hepialus humuli)|
Some years ago I had set out on a short walk to watch the sun sink. There is a spot about half a mile from Shandy Hall where there is almost 360 degrees of visibility – if you stand on a five-bar gate when you get there. Gazing around I noticed a moth, quite large, that was sort of hovering over the centre of the single-track road. Like a vertical yo-yo it was rising and falling in a rather graceful and purposeful way. Another joined it after a minute or two, and then another came. Soon there were over a dozen, all ascending and descending on invisible threads of air. I had no idea what they were but was very pleased to see something I hadn’t seen before. Two plunged together into the hedgerow, to be followed by others. On returning home I learned it was a ‘lek’ – a competitive display – by Ghost Moths (Hepialus humuli).
In the photograph above is the male, just like the ones that were beguiling and attracting the females by pheromones. Once seen this moth cannot be misidentified and the one that came to the trap last night was freshly hatched from the pupa, so fresh its wings were like laundered sheets.
The male of the species can be seen here in an earlier blogpost by UPenn intern, Walter Chen.
|Ingrailed Clay (Diarsia mendica)|
The Ingrailed Clay (Diarsia mendica) is a docile moth that appears in a wide variety of shades – the Field Guide shows nine different versions – but most can be distinguished by the square spots and the black dots close to them. The one pictured here is greyish but the moth can appear in yellowish orange, red-brown or even dark brown. It is common throughout the country and will fly through June and July.
|Barred Straw (illustration)|
The image above is of a Barred Straw (Eulithis pyraliata). For identification purposes it is an adequate representation, but because the standard form used to be the moth ‘seen as if in flight’, or ‘on display’, the naturalist is denied two indicators. When mounted in the display case the curled abdomen would not have been visible (it can be seen in the photograph below) and the gently curled hind wings would not be able to be represented meaningfully. At rest, the living moth seems to perch rather like a mantis.
|Barred Straw (Eulithis pyraliata)|