Ischnomera sanguinicollis (Fabricius, 1787)        Notable B
Although widespread this species would appear to have a very sporadic distribution in southern England and Wales; south of the Thames there are records from West Sussex to Dorset, further north from south Essex, Berkshire, Oxfordshire, Gloucestershire, Hereford and Shrewsbury. There is a single record from the south Wales coast and two, remote from any others, from north Yorkshire (NBN). The species can be abundant where found and adults occur on flowers of Crataegus (Hawthorn), Acer campestre (Field maple), A,pseudoplatanus (Sycamore), Quercus (Oak), Tilia (Lime) and Viburnum opulus (Guilder rose) (Skidmore and Hunter, 1980). Vazquez-Albalate (2003) also gives Robinia and Sorbus. They are mostly active during May and June when they may also be beaten from the foliage of these species as well as from Ulmus (Elm). The species is generally associated with old deciduous woodland but also occurs on isolated old trees in ancient landscapes. Larvae develop in moist rotten wood of various broadleaved trees and have been recorded from Acer, Alnus (Alder), Fagus (Beech) and Ulmus. Adults emerge in the autumn and overwinter at the pupation site.

Included on our Watford list from a single specimen extracted from wet wood debris taken from a rot hole in a fallen Fagus (Cassiobury park, Feb 07). The tree had fallen about twenty hours before the sample was taken and soon after was cut up and removed. When standing this rot hole would have been about 5 metres from the ground.

7-12mm (Vasquez-Albalate, 2003). A narrow and elongate species with proportionally very long elytra. Head shining, black with a rather strong metallic green lustre, densely punctate, distinctly depressed between the eyes and strongly convex on vertex, frons and labrum only weakly produced forward. Eyes convex and protruding with front edge weakly emarginate. Temples narrowed to base. Maxillary palpi dark above, testaceous below, last segment characteristic with a deep furrow on the inner edge. Antennae dark with ventral surface of segments 1-3 testaceous. 11 segmented in both sexes, third segment about twice as long as second, Pronotum shiny orange, cordiform, widest in front of middle and without lateral borders. Surface densely punctate and with a well developed fovea in front of hind margin. Elytra very elongate, dark metallic grey with faint green overtones, densely and rugosely punctate. Shoulders well developed, lateral margins weakly sinuate to rounded apex. Each elytron with five raised longitudinal lines (including sutural margin) from base to apex (or near), the outer one forming the lateral margin beyond the basal third. Abdomen entirely dark metallic. Legs long and slender, entirely dark metallic but for apical tarsal segments which are vaguely lighter. All tibiae with two spurs on inside at apex. Tarsi 5-5-4, fourth segments deeply bilobed. Claws strongly toothed at base.

Description from 1 Watford specimen at X20

Skidmore, P. and Hunter, F.F. 1980 Ischnomera cinerascens Pand. new to Britain. Ent.Mon.Mag 116:129-132
Vazquez-Albalate, 2003. European fauna of Oedemeridae. Argania.