Grypus equiseti (Fabricius, 1775)      Notable B
Widespread but local throughout the British Isles in wetland and riparian habitats. Adults occur on Horsetails (Equisetum spp.) although it is thought only Common Horsetail (E.arvense) and Marsh Horsetail (E.palustre) are hosts . Larvae develop within the stems. Adults are active from early spring following the emergence of the foodplant, they occur commonly in pitfall traps along the river Gade on Common moor.

4.1-6.7mm. Rostrum long, antennae inserted about a quarter length from apex, scrobes situated ventrolaterally, not visible from above. Underside of thorax and abdomen strongly convex making the species less depressed compared with other members of the family. Pronotum rounded, widest at centre and much narrower than the elytra, strongly punctate and with lighter scales laterally. Elytra with interstices 3,5 and 7 variously raised behind middle, appearing tuberculate, with deep, punctate striae. Legs pubescent, femora not toothed, tibiae red with apical spines. Basal tarsal segments dilated, terminal segment long with short claws.

Description from 1 Watford specimen at X20

Cawthra, 1957. Notes on Grypidius equiseti F. with a description of larvae. Proc.Roy.Ent.Soc. 32:95-106