DANAIDAE
A mostly tropical family of very large butterflies with tough bodies. The forelegs of the adults are
degenerate and the antennal clubs are slender and slightly flexed. The scent-sac on the males'
hindwing is peculiar to the family. The one British representative is a rare migrant from the New
World or, possibly, the Canary Islands /Azores. Its larval foodplant does not grow in Britain.
Danaus plexippus (Linn.) The Milkweed
p26. Migrant, very rare. There are only four Essex records (if an almost certain sighting is
included) of this our largest butterfly, involving five individuals, at least two of which were ship-
assisted (see Guide). 49 Loughton, end July 1982 (Bretherton & Chalmers-Hunt, 1983).
MOTHS
LASIOCAMPIDAE
A family of small to very large moths, including the eggars, with broad wings which are some shade of
brown. They have stout, furry bodies and are strong fliers, the males of some species being diurnal.
Both sexes have pectinate antennae - the males' antennae being especially feathery. The wings lack a
frenulum and there is an enlarged basal region on the hindwing. The adults cannot feed. The larvae are
long and very hairy and spin tough cocoons inside which they pupate. Most feed on rosaceous shrubs
or heather but there are species which feed on non-woody broad-leaved plants and one species (the
drinker) eats grass. Amongst the ten British species (all known in Essex) four spend winter as eggs,
four as larvae, one as a pupa and one emerges in mid-winter.
Poecilocampa populi (Linn.) December Moth
p46. Resident, widespread and fairly common.
Trichiura crataegi (Linn.) Pale Eggar
p46. Resident, fairly widespread and locally common.
Eriogaster lanestris (Linn.) Small Eggar
p46. Resident, very local and rare; no certain record since 1970 (see Guide).
Malacosoma neustria (Linn.) The Lackey
p46. Resident, widespread and common.
Malacosoma castrensis (Linn.) Ground Lackey
p46. Resident and local, locally common; restricted to the coasts and estuaries.
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