Author: (Fabricius, 1775)
Clover seed moth
Species Overview:
Adult: 8-10 mm wingspan; forewing black-brown except for four pairs of sharply defined interspaces between costal strigulae and a characteristic dorsal blotch which is divided into four white striae.
Egg: deposited singly on the leaves of the food plant.
Larva: head pale yellowish brown; prothoracic and anal plates varying from light to dark brown; abdomen cream-white, gradually acquiring a reddish tinge as the larva develops and becoming bright red when it is fully fed.
Pupa: in a whitish silken cocoon amongst litter on the ground.
Taxonomic Description:
Male:
G. compositella male
G. compositella adults
External characters: 8-10 mm wingspan. Forewing ground colour white or cream-white, overlaid with black-brown except four pairs of sharply defined interspaces between costal strigulae, some of the interspaces producing or terminating in short, bluish metallic striae, and a large, slightly outward-oblique, quadrate dorsal blotch which is transversely marked by three parallel, black-brown striae, the basal one being surmounted by a short plumbeous dash; basal area paler or suffused with light grey and concolorous with thorax and tegulae; fasciate markings obsolete; ocellus represented by a thick, violet metallic stria arising from tornus; cilia light grey, blackish basally. Hindwing white, infuscate distally and along termen; cilia white, suffused with grey at apex and along termen, with a dark sub-basal line (Bradley et al., 1979).
male genitalia G. compositella
Genitalia: Tegumen with numerous scattered bristles. Valva rather narrow, broadly grooved in area of neck, its dorsal margin (costa) straight; cucullus oval. Aedeagus broad.
Female:
External characters: Similar to male but with hindwing uniformly fuscous-brown.
female gen. G. compositella
Genitalia: Lamella postvaginalis weakly sclerotized, consisting of two (touching) plates. Anterior (cup-shaped) part of sterigma fairly well sclerotized. Ductus bursae with short membranous posterior part, anterior to this it is sclerotized, and broadening towards corpus bursae. Signa similar in shape and size.
Biology:
The species is bivoltine; the first generation of moths occur in May and June and the second generation in August. They frequent clover fields, meadows and grassy places, especially on rough chalky or sandy ground where there is an abundance of clover. The males may often be seen in numbers flying rapidly about the clover on sunny afternoons in calm weather and are conspicuous because of their white hindwings. The females fly towards sunset. They deposit their eggs singly on the leaves of the food plant. They hatch after 4-6 days. Larvae then undergo 5 larval stages. The larvae of the first generation feed in the stems, tunnelling upwards from the base; those of the second generation usually feed in spun terminal leaves and flowerheads, and sometimes in the pods. Pupation takes place in a whitish silken cocoon amongst litter on the ground (Bradley et al., 1979; Bovey, 1966).
Host plants:
Trifolium pratense, Trifolium repens and probably other species of clover; also recorded on Glycine max (soya bean), Medicago sativa, Melilotus, Lotus corniculatus and other Leguminosae.
Damage:
Larvae feed in flower buds, flowers and ovaries of clover and lucerne.
Also recorded on soya bean (Zandigiacomo and dalla Monta, 1982).
Distribution:
Europe to Asia Minor, Mongolia, China and Eastern Russia; North America.
Pheromone:
Pheromone unknown.
Attractantia:
E 8E 10-12Ac (Witzgall et al., 1996b)
Grapholita caecana (Schläger)
Another species of Grapholita feeding on Medicago sativa which is not included in the key is Grapholita caecana (Schläger).
Grapholita caecana adult
Grapholita caecana adults
This species has brownish grey forewings and well-defined blackish brown costal strigulae; the interspaces between these are white and produce plumbeous striae. The ocellus is poorly developed. This species lacks the characteristic dorsal blotch, which is divided into four white striae, that is present in Grapholita compositella.
It occurs from Europe to Northern Iran, Northern China and Eastern Russia.
Genitalia:
male genitalia G. caecana
Apex of tegumen with tufts of bristles (tegumen with numerous scattered bristles in G. compositella )
female genitalia G. caecana
Anterior part of sterigma broad