Barred tooth-striped moth  (Trichopteryx polycommata)

Classified as Nationally Scarce in Great Britain (3).

The Barred Tooth-striped is a greyish coloured moth. The caterpillars are green with two white lines and a dark central line passing along the back. There is also a white line along the sides (4).

Although this scarce moth has a wide distribution in the UK, it occurs only locally. Good populations are known in south Cumbria, Breckland and the Hampshire/ Wiltshire border (3). A handful of populations occur elsewhere in southern England (3), and the range reaches through central Europe to Russia (4).

Found in clearings and rides in woodlands with calcareous or clay soils and in calcareous downland. In all habitats there must be a supply of the larval foodplants, wild privet (Ligustrum vulgare) or ash (Fraxinus excelsior) (3).

Adults are on the wing from mid-March to mid-April and fly at night. Further north, the adults emerge slightly later on in the year. The caterpillars hatch from the eggs laid by the adults, and are active between May and June; the pupal stage then develops, and overwinters (2). The adults emerge the following spring, starting the cycle once again. This type of life-cycle takes a year to be completed, and is known as 'single-brooded' or 'univoltine', as a single generation or brood is produced during that time.

On downland, the species has suffered as a result of habitat loss and scrub invasion due to inappropriate management. New methods of woodland management have caused problems by removing the foodplant during timber extraction. Woodland clearings and rides can become overgrown and the foodplant shaded out following abandonment or neglect (3).

The Barred Tooth-striped moth is a priority species under the UK Biodiversity Action Plan (UK BAP), and the Species Action Plan produced aims to maintain all known populations, with enhancement of these populations by the year 2010 (3). A number of colonies occur within existing Sites of Special Scientific Interest (SSSIs) and nature reserves (3). Suggested measures to help the species include appropriate habitat management, surveying, monitoring and ecological research (3).

Further reading on moths:
Leverton, R. (2001) Enjoying Moths. Poyser, London.
Skinner, B. (1984) Moths of the British Isles. Penguin Books, Harmondsworth

Information authenticated by Adrian Spalding.

• Calcareous: containing free calcium carbonate, chalky.
• Larval: of the stage in an animal's lifecycle after it hatches from the egg. Larvae are typically very different in appearance to adults; they are able to feed and move around but usually are unable to reproduce.
• 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.
• Rides: the footpaths and access tracks which run through and divide blocks of trees in woodland. Many rides contain a mixture of rich flora and structure, and provide different habitat conditions for a range of wildlife.
• 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.

1. National Biodiversity Network Species Dictionary ( January 2003) http://www.nhm.ac.uk/nbn/
2. Skinner, B. (1884) Moths of the British Isles. Penguin Books, Harmondsworth.
3. UK BAP Species Action Plan (December 2001): http://www.ukbap.org.uk
4. South, R. (1961) Moths of the British Isles. Frederick Warne and Co. Ltd, London.