Key to the British BRACHYCERINAE

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1.

Without eyes.

Eyes present. Size larger, >2.5mm. Funiculus 6-segmented.

Eyes present. Size smaller <2.5mm. Funiculus 6 or 7 segmented.

2.

Antennae inserted near the rostral apex; prorostrum quadrate or nearly so. [Inner apical margin of pro-tibiae only weakly produced into a tooth.]

Antennae inserted further from the rostral apex, prorostrum obviously elongate. [Inner apical angle of pro-tibiae produced into a strong tooth.]

3.

Pronotal disc tuberculate, each tubercle with a tiny puncture. Scutellum pale, clothed with narrow pale scales. Third antennal segment at most only slightly longer than the fourth. Dark grey with a distinct mottled pattern made of pale broad scales. 3.3-5.1mm.

Pronotal disc closely and confluently punctured. Scutellum dark, without pale scales. Third antennal segment obviously longer than the fourth. Dark grey; pale scales foming an indistinct pattern on the elytra. 3.8-6.8mm.

4.

Pronotum and elytra distinctly coloured (fig. 1); dark with abruptly pale lateral margins, elytral apex extensively pale. Elytral interstices 3, 5, and 7 raised in places. [elytra convex and deep, only slightly broader than deep (lateral view), and sinuate before the apex.]

Dorsal colour not as above. Elytral interstices equal and at most weakly convex.

Fig. 1: Grypus equiseti

5.

Eyes more convex. Anterior margin of pronotum smoothly rounded, without a median notch. Sutural interstice with dense scales. Narrow and parallel-sided species, appearing more elongate. [Female rostrum distinctly longer.]

Eyes less convex. Anterior margin of pronotum notched at centre. Sutural interstice glabrous or with only scattered scales. Broader species, appearing less elongate.

6.

Elytra distinctly impressed before the apex, less elongate, and sinuate subapically so that the apex appears to protrude beyond the parallel lateral margins.

Elytra smoothly convex before the apex, laterally more continuous so that the apical margin is evenly curved to the apex.

7.

Fourth antennomere more elongate, about twice as long as wide, and distinctly longer than the fifth, eighth quadrate or only slightly elongate. Scales on elytra denser and not forming a distinct pattern. 3.8-4.6mm.

Fourth antennomere less elongate, about 1.5X longer than wide, and equal to the fifth, eighth slightly transverse. Scales on elytra less dense and often forming a distinct pattern. 3.3-4.4mm.

8.

Rostrum less curved, distinctly dilated apically and dark brown or black; lighter only at the apex.  3.5-4.3mm.

Rostrum more strongly curved down, only weakly dilated towards the apex and pale brown to red throughout. 3.3-5.1mm.

9.

Inner margin of pro-tibiae with a series of small sharp teeth. [Scales on elytra usually form a linear tessellated pattern on alternate intervals. 5.5-8.7mm.

Inner margin of pro-tibiae smooth.

10.

Dorsal surface shiny and glabrous. Pronotum more densely punctured. 5.3-7.9mm.

Dorsal surface dull and with scattered pubescence, usually in ill-defined patches.

11.

Larger, 5.5-7.3mm.  Elytra more densely and uniformly pubescent to lateral margins.

Smaller, 3.4-5.1mm. Elytra less densely and uniformly pubescent, with glabrous patches laterally.

12.

Funiculus 6-segmented. Pro-tibiae prolonged into a sharp tooth at the inner apical angle. Third tarsomere very deeply bilobed and surrounding the terminal segment. Antennal club short and abrupt. 1.4-1.8mm.

Funiculus 7-segmented. Pro-tibiae without conspicuous apical tooth. Third tarsomere lobed but narrow, appearing normal, the terminal segment obvious. Antennal club elongate and more gradual.

13.

Lateral pronotal margins with dense pale scales. Pro-tibiae smooth internally to the apical tooth.

Lateral pronotal margins with at most a narrow strip of pale scales. Pro-tibiae with a small, sharp internal subapical tooth.

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