Lunar yellow underwing moth  (Noctua orbona)

Lunar Yellow Underwing

Facts

Kingdom Animalia
Phylum Arthropoda
Class Insecta
Order Lepidoptera
Family Noctuidae
Genus Noctua (2)
Size Wingspan: 37 - 42 mm (4)

Status

Classified as Nationally Scarce in Great Britain (1).

Description

The scarce Lunar Yellow Underwing has dark brown forewings but deep yellow hindwings with a broad brownish-black border. There is a black spot on the margin of the forewing (the 'costa') near the apex (4). The moth can suddenly display the hind wings when threatened in order to alarm potential predators (3).

Range

This species has undergone a sustained decline but formerly had a wide distribution in the UK. The current stronghold is in the Brecklands of Norfolk and Suffolk (1). It is also currently reported from north east Scotland, and caterpillars have been found in the Wirral (Cheshire) in 2002 (4). Elsewhere it is known from North Africa, Central Asia and the Middle East, and is a local species in Europe, but is absent from the south-west of Spain and Portugal, southern Greece and Ireland (1).

Habitat

Generally associated with open grassy sites amongst woodland and heathy, sandy or calcareous areas (1).

Biology

Adults of this single-brooded species fly between late June and September, and possibly aestivate during August (2). Caterpillars are present from October to April and feed at night on fine grasses (2). The pupal stage occurs underground (1).

Threats

Destruction of fine-grass heaths, and sheep grazing and close-mowing of tufted grasses are the major threats facing this species (4).

Conservation

The Lunar Yellow Underwing moth is a UK Biodiversity Action Plan (UK BAP) priority species. The Species Action Plan aims to maintain the current range of the species. Survey and research has been largely carried out in the Brecks (4).

Further Information

Further reading on moths:
Leverton, R. (2001) Enjoying Moths. Poyser, London.
Skinner, B (1998) Moths of the British Isles. Viking, London.

Authentication

Information authenticated by Gerry Haggett.

Aestivation: period of dormancy occurring in hot, dry periods, analogous to hibernation in winter.
Calcareous: containing free calcium carbonate, chalky.
Pupal stage: stage in an insect's development, when huge changes occur that reorganise the larval form into the adult form. In butterflies the pupa is also called a chrysalis.
Single-brooded: (also known as 'univoltine'). Insect life cycle that takes 12 months to be complete, and involves a single generation. The egg, larva, pupa or adult over winters as a dormant stage.

References

  1. UK BAP Species Action Plan (January 2002):
    http://www.ukbap.org.uk
  2. Skinner, B. (1984) Colour Identification Guide to Moths of the British Isles. Viking Press, London.
  3. Pers. observation from images.
  4. Haggett, G. (2002) Pers. comm.