Clay Fan Foot

A single brooded species, adult Clay Fan-foot moths are on the wing from July to early August. The caterpillars are active between the end of August and early June feeding on fallen oak leaves, and overwinter whilst small (2). It is likely that caterpillars inhabit the leaf-litter until pupation, feeding on oak leaf-detritus (5).

The Clay Fan-foot moth has been identified as a priority species for conservation action under the UK Biodiversity Action Plan (UK BAP). The Species Action Plan aims to maintain all existing populations, but no specific action other than monitoring has been proposed. The majority of the known populations currently occur within existing Sites of Special Scientific Interest (SSSIs). Conservation action targeted at other species that inhabit lowland coppiced woodland such as the Drab Looper moth (Minoa murinata) will be likely to benefit this species too (1).

Adult Clay Fan-foot moths are pale ochreous brown in colour with darker brown cross-lines on both the fore- and hind-wings (3). When fully grown, the caterpillars develop a downy texture, and are brown in colour with three lines along the back (3).

Found in coppiced areas and sheltered clearings in mature oak woodlands (5).

This species has always been restricted to the south-east of England, but has undergone a massive 70% reduction in range, and has been lost from Hampshire, Essex and Wiltshire. It is now known from just a handful of woodlands in Surrey, Kent and Sussex. Outside of the UK it is found in southern parts of Europe reaching east to China, Iran and southern Russia (1).

Classified as Nationally Scarce in Great Britain (1).

It is thought that the decline of this species is due to the reduction in suitable habitat within its range, namely oak-dominant mature woodland or traditionally coppiced woodland with a high density of oaks left as standards (5).

Paracolax tristalis, the clay fan-foot, is a litter moth of the family Erebidae. The species was first described by Johan Christian Fabricius in 1794. It is found in the Palearctic realm.

The wingspan is 28–35 mm. The moth flies from June to August depending on the location.

Figs. 5, 5a, 5b larvae in various stages of growth

The larvae feed on various shrubs and deciduous trees.