Represented in Britain by two species included in two genera within the tribe Nanophyini of the Nanophyinae;
Nanophyes marmoratus (Goeze) and Dieckmanniellus gracilis (Redtenbacher). These are small, 2mm or less, and immediately
recognised as weevils with long, slender appendages and rostra. The compact oval form is reminiscent of
Apionidae but they are distinct in possessing geniculate antennae, the
scape being almost as long as the funiculus and club combined. The possession of long trochanters, readily appreciated
in side view in set specimens, will separate both Apionidae and Nanophyidae from Curculionidae
but the general appearance will distinguish our species from other similar sized weevils; the pronotum is strongly
narrowed from base to apex and both species are characteristically marked. In each case the base of the elytra is black, in
D.gracilis the apical two thirds are clothed in yellow scales while in N.marmoratus there are two transverse
bands of yellow or white scales.
D.gracilis is a rare and very local insect with a few scattered records from southern England; Bershire, Dorset,
Hampshire, the Isle of Wight, Surrey and Sussex. It ooccurs on water purslane (Lythrum portula) in damp and muddy
places, the host is widespread and common and should be examined for the beetle as a matter of course.
N.marmoratus is common throughout England and Wales and extends into Scotland, it occurs on purple loosestrife
(Lythrum salicaria), a common and widespread species of river banks, ditches and marshes.
|
