30-Mar London’s Moth Magic

The Hebrew Character moth is easily identified by the so-called Hebrew character motif on its wings. Sometimes it is the only moth caught in a moth trap. Other moths, such as the Grey Shoulder Knot Lithophane ornitopus, Orange Underwing Archiearis parthenias and Red Chestnut Cerastis rubricosa have a more local distribution. The Orange Underwing is easily recognised by the orange spots on its underwings, noticed as brief flashes when it starts to fly. A rare form, with yellow rather than orange underwings, is one of Wimbledon Common’s rarities. The Red Chestnut can be seen on willows and around lights. It has a habit of flying later in the night. Other moths, such as The Engrailed Ectropis bistortata and the Shoulder-stripe Anticlea badiata are more common in non-urban areas. The Engrailed has handsome grey-brown camouflage markings and the Shoulder-stripe, not surprisingly, a black shoulder stripe across the top of its brown wings or at least cross-bands edged in black.

Two groups of moths that are more common than most this month are the quakers and the drabs e.g. the Common Quaker, Twin-spotted Quaker, Small Quaker, Clouded Drab and Lead-coloured Drab. These small moths, as a group, tend to be grey and brown, but with distinctive circles on their wings. The Common Quaker Orthosia cerasi is often found in large numbers in moth traps. The twin-spotted Quaker Orthosia munda is usually easily recognised by its paired black spots visible on each resting wing, although annoyingly there is also a spotless form. The Clouded Drab Orthosia incerta is a handsome noctuid species, with distinctive small, irregular circles on its wings and the Lead-coloured Drab Orthosia populeti is again unsurprisingly lead in colour. It is often seen at dusk around willows and aspens. Some moths, such as the Sword Grass Xylena exsolenta are immigrants. Other rarities this month are the White-marked Cerastis leucographa and the Light Orange Underwing Archiearis parthenius. The White-marked was a speciality of Whippendall Wood, in Hertfordshire, but nowadays any seen are just likely to be wanderers.

The most striking of March moths are the Early Grey, Early Thorn, Pine Beauty and, best of all, the Oak Beauty. The Early Grey Xylocampa aerola is yet another noctuid, this time with handsome, grey camouflage markings. It is common from the second week of March in gardens. Later, it will feed on the garden honeysuckles, which are so widely planted in London. The Early Thorn Selenia dentaria is one of the most common of all the Thorns. It looks very much like a brown leaf, but with a handsome scalloped edge. The Pine Beauty has reddish and grey forms, both with large pale kidney-markings on their wings. These forms are in equal numbers and the moth is always found near our native Scot’s Pine appearing to ignore all the foreign pines planted in gardens.

Lastly, the Oak Beauty Biston strataria is, as its name suggests, a great beauty. It is a large moth with the wingspan of five centimetres and is most numerous in mature oak woodland. The two broad usually brown bands of different widths across its forewings allow easy identification and the male has handsome feathered antennae. Luckily, they come to the light and can also sometimes be found newly emerged at the base of tree trunks during the day.