Phyllobius maculicornis Germar, 1824
This is the only UK member of the present subgenus which includes a further ten species in Europe, it occurs commonly from lowlands to the tree line in mountain areas throughout Europe and extends north into the UK and some southern provinces of Fennoscandia, further east it generally common as far as eastern Siberia and is among the most common species in many areas. Here it is common throughout England and Wales, although less so in the west, and more local and sporadic further north to the Scottish Highlands and in south west Ireland. Adults appear in April and persist into September or October, peaking in abundance during May and early June, they are widely polyphagous and feed on a range of deciduous trees and shrubs as well as, though less frequently, herbaceous plants. They may occur in any dry or moderately damp habitats, typically deciduous and mixed woodland, parkland, scrub, hedgerows, road verges and even domestic gardens although they rarely appear in numbers and contrary to the common name are not a pest of fruit trees in the UK. Mating pairs may be seen on foliage and umbel flowers etc. through the spring and early summer and females oviposit directly into the soil, usually laying a dozen or so eggs near to the base of suitable plants on which the larvae will feed. The larval stage is entirely subterranean, they feed externally on roots through the summer, overwinter deeper in the soil, and finish developing in the spring, pupation occurs during April and May and adults appear after two or three weeks, depending on conditions. There is a single generation each year. Beating or sweeping suitable host material is the best way to sample adults although they can be common on hawthorn blossom in the spring and on a range of flowers through the summer.
Phyllobius maculicornis 1
Phyllobius maculicornis 2
4.0-6.3 mm. Very distinctive due to the strongly toothed front femora, bright metallic green or blue-green colour and the form of the scales and setae. Scales to the head and pronotum elongate and oval, those on the elytra less elongate and more rounded, pronotum without setae, elytra with short semi-erect setae. Head with prominent convex eyes and long diverging temples, evenly convex at the base and depressed medially between the eyes, rostrum short and broad with straight scrobes which are placed laterally but widely visible from at the rostral apex. Antennae long and slender, scape curved and only weakly broadened from the base, all funicular segments elongate and club long and only a little broader than the eighth segment, typically reddish brown with the club and the apex of the scape darkened (hence the specific name) but variable and sometimes entirely pale. Pronotum transverse; widest behind the middle and narrowed to a weak sub-apical constriction and obtuse posterior angles, surface evenly convex and without structure. Elytra much broader across widely-rounded shoulders than the base of the pronotum, larger and more dilated in the female, sometimes almost parallel-sided in the male, densely scaled but mostly on the interstices so the striae are easily seen; in most specimens the interstices have a row of small scale-less spots that reveal the black cuticle. The elytral setae are distinctive; they are mostly much shorter than the width of the interstices, creamy or yellow and truncate. Legs long and robust, the femora and tibiae are usually dark and covered in metallic elongate scales and the tarsi are reddish but this is variable. All femora strongly toothed below and all tibiae abruptly expanded at the apex, third segment of all tarsi strongly bilobed.