Protapion fulvipes (Geoffroy in Fourcroy, 1785)
This is a widespread and generally common or abundant species throughout the Palaearctic region north to Scandinavia and the UK where it is abundant across England, Wales and Southern Scotland and more sporadic and local further north including the Western Isles and Orkney, and in many countries it is the most abundant member of the family. Adults occur year-round and may be found wherever the host plants grow; roadsides, wasteland, wooded borders and grassland generally. Hosts include various species of clover but more especially Trifolium repens L. (white clover), T. hybridum L. (alsike clover) and T. spadiceum L. (large brown clover) but not, apparently, T. pratense L. (red clover), and throughout the range the species is an occasional serious pest of cultivated clovers where up to 50% of seeds may be lost to large infestations of larvae. Adults appear on host plants in the spring when they feed upon developing foliage during a period of maturation feeding before ovipositing begins in April or May. Eggs are laid in the flowers, either attached to the corolla by a secretion or placed among the anthers, usually only a single egg is laid in each floret but occasionally there are two. Larvae emerge after about 10 days and develop within the flower consuming seeds, fully grown they are 2-3mm, curved and pale with a darkened head but other similar species may also be found in the same situation, they are fully-developed within 20 days and pupation occurs in the flower where the adults eclose after about 10 days. New generation adults remain on the plants until October or November when they fly to trees and shrubs to form large aggregations prior to overwintering among leaf-litter etc. Aggregations form once again in the spring before the adults migrate to spring feeding sites; both spring and autumn migrations occur in the evening or even at night and at such times they may occur at light or in flight-interception traps in numbers. Sampling is straightforward as the adults may be swept wherever the host is growing and larvae are easily found in older and withered flowers, by mid-May the adults should occur in large numbers in the sweep-net.
Very easily identified among our UK Protapion species; 1.8-2.2mm, all tibiae substantially pale and only the base of the antenna is pale, the funiculus segments are progressively broader towards the apex so that the club is less abruptly set-off than in P. nigritarse (Kirby, 1808), our only other Protapion with pale tibiae.
Elongate with rounded and strongly convex elytra, in lateral view with a distinct angle between the pronotal and elytral bases. Head quadrate with strongly and distinctly punctured vertex, striated frons and convex and prominent eyes. Rostrum in the female much longer than the pronotum with antennae inserted behind the middle, in the male only slightly longer than the pronotum and with the antennal insertions near the middle. Antennae dark with at most the basal half pale, distal segments of the funiculus broader than the basal segments, segment 8 quadrate to transverse, club elongate and rather narrow, not abruptly set-off against the eighth segment. Pronotum quadrate to slightly transverse, rounded laterally and constricted before the base and apex, broadest across the basal margin, surface strongly and moderately densely punctured. The basal impression is very variable, from evanescent to short and deeply impressed. Elytra with distinct shoulders and almost straight in the basal third, widest about the middle and evenly curved to the apex, generally broader and more strongly curved in the female. Striae distinct and strongly punctured, interstices only weakly convex; those near the suture often almost flat, densely and very finely punctured and pubescent and sometimes faintly transversely rugose. Coxae dark except the pro-coxae in the male (and very rarely also in the female) which are pale. Trocanters and femora pale, tibiae extensively pale; meso- and meta-tibiae, and sometimes also the pro-tibiae, darkened towards the apex. Tarsi extensively dark; sometimes with part or the entire basal segment pale.
PROTAPION Schilsky, 1908
This is a Palaearctic genus of about 50 species which fall into two rather distinct groups; those with distinctly metallic elytra, and those with black elytra which include most of the species and all of those occurring in the UK. All occur on various Fabaceae, more especially clovers, where the larvae develop in flowers and adults feed on the leaves. Although specific identification can be very difficult the genus is distinct and readily recognized by the glabrous and highly-arched elytra which form a distinct angle with the pronotum in side view, distinct humeral calli, long and cylindrical rostrum and long slender legs which in the majority are to some extent pale, the UK species P. filirostre (Kirby, 1808) is entirely dark but otherwise obvious.
Our UK list includes 12 species; P. ryei (Blackburn, 1874) from the Western Scottish Isles and Orkney, variously described as a distinct species, is now included as a subspecies of P. assimile (Kirby, 1808). Several are widespread and abundant and should soon be found by general sweeping among suitable hosts and in late spring and summer they usually occur in large numbers. The larvae are easily found by examining flower buds that have failed to open or develop properly. Among our abundant species are P. apricans (Herbst, 1797), P. assimile, P, trifolii (Linnaeus, 1768), P. difforme (Germar, 1818), P. fulvipes (Geoffroy in Fourcroy, 1785) and P. nigritarse (Kirby, 1808).