Key to the British TROGIDAE
1.
Pubescence on the base of the antennae, and scales/pubescence on the pronotum and elytra, black. Tubercles on elytral interstices 1,3,5,7 and 9 large and shiny; punctured and with black scales towards the apex.
Pubescence on the base of the antennae and scales/pubescence on the pronotum and elytra pale; light brown to yellow. Tubercles on the elytral interstices small and dull, punctured and covered with scales or scale-like pubescence.
2.
8-10mm. Sutural stria almost as wide as the first and second interstices. Interstices with regular transverse raised areas between rows of granules. Hairs on the elytra pale yellow.
5-8mm. Sutural stria less than half the width of the first and second interstices. Interstices with two rows of fine stria between rows of granules. Hairs on the elytra darker, generally brown.
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