Parethelcus pollinarius (Forster, 1771)

A common amd widespread species occuring throught the British Isles including Orkney and Shetland (Morris). Found throughout the Watford area and likely to be present wherever the host, Urtica dioica (Stinging Nettle), occurs. Adults appear in late March or early April depending on season and may be swept from the host or from vegetation in the vicinity of the host; we have found them on the undersurface of large Rumex leaves at this time. They almost always occur as individuals or in pairs, unlike Nedyus quadrimaculatus which usually occur in large numbers; sweeping along a bank of nettles may produce a specimen every four or five metres or so and where nettles cover a large area, as they do alongside the river Colne in Radlett road, the same relatively sparse occurence is seen. With a little experience the larger Parethelcus is obvious among large numbers of Nedyus. We have recorded them from town centre gardens (where nowadays the host is generally rare), road verges, wasteland, parkland and woodland etc. They do not seem to increase in numbers and persist through June and usually into the first or second week of July. Larvae develop within stems and pupation occurs in the soil.

2.8-4.0mm (Morris) A broad and dorsally rather flat species, entirely black but for the tarsi and antennae which are mostly testaceous. Head closely and coarsely punctured and with recumbent pale scales, weakly depressed between round, convex and protruding eyes. Rostrum long and punctured, puncturations a little stronger beyond antennal insertions. Antennal scape gradually and weakly broadened towards apex, funiculus seven segmented and club elongate and pointed. Inserted about a third from apex in male, a little further back in female. Pronotum transverse (3:2) with a strongly raised and sharply pointed dorso-lateral tubercle, narrowed to front margin which is usually raised. Surface strongly and closely punctured and with sparse pale scales. Depressed in middle behind front margin and deeply so in front of hind margin, these are somtimes weakly confluent so forming an indistinct channel. Scutellum not visible, scutellar area depressed. Elytra quadrate with very prominent shoulders and weakly impressed striae. Interstices flat, tuberculate apically so that interstices 1-9 form a transverse row of tubercles above elytral apex, below these each elytron has a discreet patch of white scales although these may be virtually confluent due to scales at elytral apex. Ninth interstice with a series of tubercles from below shoulder to apex, each tubercle with a short, dark seta. Upper surface covered, or almost covered, with small, elongate pale scales which range from amost blue to testaceous. These are generally evenly distributed although there may be a vague tendency towards patches. All femora strongly toothed, mid and hind tibiae with apical spur on inner side in male, female without spurs

Description taken from 16 Watford specimens at X20