Psylliodes luteola (Müller, O.F., 1776)
This is a mostly southern and central European species which extends east into Asia Minor and western Russia, it is present on most of the Mediterranean islands and is common across much of North Africa, to the north, where it tends to be more sporadic and scarce, it reaches the UK and the southern Baltic countries. In the UK it is very local in southern central England extending north to Derbyshire although it seems to be increasing in abundance and range; typical habitats are grassland and arable margins, open deciduous woodland and well-vegetated road verges and in recent decades it has become an occasional and sometimes serious pest of oilseed rape. The species is widely polyphagous although its association with rape seems to be confined to the UK; it develops on a range of grasses including cultivated species such as wheat and barley and adults also feed on the foliage of various broadleaved trees but especially oaks, birches, poplars, willows, hornbeam and elm, they produce small holes in tender leaves and usually do not injure the hosts although large populations may skeletonise small areas of foliage and specimens have been recorded feeding on wheat seeds. In the UK adults are active from May until October, peaking in abundance from late August to late September, but specimens are often recorded later than this as they overwinter, on the continent they occur over a much longer season and in southern regions they appear very early in the spring. The life cycle is poorly understood in the UK but reproduction occurs in late summer and larvae develop continually until the following spring; those from the earliest eggs producing adults in late summer and autumn and those from later batches, which seem to be the majority, completing their development during the following spring. In warmer continental areas the life cycle is less diverse as adults are able to overwinter and breed earlier in the year, larvae complete their development and pupate during the summer and are not known to overwinter. Eggs are laid in small batches at the base of stems or on lower leaves and after an initial period of feeding the larvae move down the plant to feed on roots, in the UK mostly through the autumn and winter, and pupate in a subterranean cell during the following spring. Adults may be swept from vegetation by hedgerows or field margins etc. but in south Hertfordshire, where they are locally common, we find them almost exclusively on low vegetation beside woodland pathways; they vary in abundance and may be common following several years of absence, they fly well and so might suddenly appear in well worked areas.
Psylliodes luteola 1
Psylliodes luteola 2
2.1-3.2 mm. Broadly-oval and more-or-less continuous in outline, entirely shiny pale red to yellow, rarely darker reddish-brown, with the antennal apices and often the hind femora darker. Head visible from directly above, with sparse and moderately strong punctures and distinct but weak and sometimes incomplete frontal impressions, antennae 10-segmented and filiform, extensively pale but usually darkened from the sixth or seventh segment. Pronotum transverse; from above broadest in front of near-perpendicular posterior angles and narrowed to a rounded anterior margin, surface smoothly convex, with variously developed but usually weak basal impressions and moderately strong and dense punctures but without finer punctures between. Elytra long-oval; broadest about the middle and narrowed to rounded shoulders and a continuously-curved apical margin, with strongly punctured striae, including a long scutellary striole, from the base and very finely punctured, almost flat, interstices. Legs long and slender, with massively developed hind femora and hind tibiae that are strongly-curved externally. Males may be distinguished by the dilated basal segments of the front tarsi.