Psylliodes dulcamarae (Koch, J.D.W., 1803)
Suborder:
Superfamily:
Family:
Subfamily:
Genus:
POLYPHAGA Emery, 1886
CHRYSOMELOIDEA Latreille, 1802
This generally common species occurs from lowlands to about 1000 m throughout Europe from Portugal to Ukraine and Asia Minor in the south, to the UK and southern provinces of Fennoscandia in the north, and to the east it extends east through Kazakhstan and Russia to Mongolia and southern parts of Siberia. Here it is locally common across south and central England below the Wash, and scattered and generally scarce in the West Country, around the Welsh coast, and further north as far as the Humber. Adults occur year-round although they may be absent for a while between generations in the summer, they overwinter among leaf-litter and tussocks and are generally active between March and October, peaking in abundance during May and June and again, though less so, during September. Typical habitats include anywhere the host plant, bittersweet (Solanum dulcamarae L.), is common, damp woodland and wetland margins, hedgerows, parkland and moorland and coastal dunes, and it also occurs commonly on disturbed sites such as agricultural borders, gardens and allotments. Breeding occurs in the spring after a period of feeding when the adults produce numerous small holes in host foliage, and continues into early summer, oviposition occurs in May and June (and probably a little later) when females deposit small batches of eggs into or onto host stems. Larvae mine the stems and their presence can often be detected by small round holes in the stem through which they expel faeces but whether these are made by the larva or the female is not known, they pass through three instars and when fully grown they emerge from the stem and fall to the ground where they will pupate in an earthen cell. New-generation adults emerge during August and September and will feed before overwintering; at this time affected host plants can become severely damaged with entire leaves skeletonised, this damage often being added to by Psylliodes affinis (Paykull, 1799) which tends to be common at this time. Adults are easily sampled by sweeping host plants; they usually occur in numbers and as they fly well may suddenly appear at new sites.
3.0-4.0 mm. Elongate-oval and very convex, body dark metallic blue, antennae black with two or three basal segments yellow, legs dark brown, the hind femora usually darker and the tarsi paler brown. Head only narrowly visible from above; smoothly convex and finely punctured between large convex eyes, frontal impressions usually faint or indistinct, often obscured by punctures, antennae 10-segmented with all segments elongate. Pronotum transverse, broadest across almost perpendicular posterior angles and narrowed to distinct anterior calli, from above with a small projection about the middle, surface with a mixture of larger and smaller punctures throughout. Elytra broadest behind sloping shoulders and narrowed in almost straight lines to a continuous apical margin, striae punctured and distinct to the apex, interstices finely punctured throughout. Front and middle femora normal, hind femora greatly developed and excavate behind to receive the tibiae. Hind tibiae smoothly curved and without obvious teeth or spines along the internal margin, apical margin excavate towards a bidentate apex, the tarsi inserted at the base of this excavation. Tarsi pseudotetramerous; basal segment of the hind tarsi long and slender, basal segment of the front tarsi much broader in the male.