Polyploca ridens (Fabr.) Frosted Green
p44. Resident, fairly widespread and locally fairly common.
GEOMETRIDAE
A very large family of moths characterised by larvae which possess only two pairs of functional
prolegs; the gap between true legs and prolegs causes them to walk by drawing themselves up into an
arch and then reaching forwards - hence the English name of 'loopers'. Most species pupate
underground. The majority of the adults have broad wings, slender bodies and the haustellum
developed. Nearly all fly by night. A futher description is given for each subfamily.
Archiearinae
The two closely related British species fly by day after emerging in early spring from overwintering
pupae. The haustellum is fully developed. The larvae are monophagous on trees. Both species are
resident in Essex.
Archiearis parthenias (Linn.) Orange Underwing
p95. Resident, local; fairly common in a few districts; may have declined. 49 Epping Forest
(EFCC); 51 Matching, assumed vagrant, 1982 (AJF); 67 Grays Chalk Quarry NR, fairly common,
1982 (DJLA); 60 High Woods (two sites), 1984 (EB); 63 Thaxted, assumed vagrant, 1972 (AJF);
92 Kingsford, early 1970s (JY).
Archiearis notha (Hb.) Light Orange Underwing
p96. Resident, very local; 92 Friday Wood, 1985 (JY).
Oenochrominae
The single British species emerges in March. The haustellum is degenerate and the adult cannot feed;
the female is wingless. The larva is polyphagous on broad-leaved trees and shrubs.
Alsophila aescularia (D. & S.) March Moth
p96. Resident, widespread and common.
Geometrinae
With one exception, the British species are emerald green moths. Both sexes have fully developed
wings and the haustellum is functional. The notch on the head and, in some cases, the first thoracic
segment is a characteristic feature of the larvae. They are oligophagous on trees or woody shrubs.
Winter is passed as a pupa in a flimsy cocoon. All ten British species have been found in Essex and
seven are resident
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