COLEOPTERA > POLYPHAGA > ELATEROIDEA > Cantharidae

In addition to the fifteen Cantharis species, the Cantharinae subfamily includes a further nine typical soldier beetles; the very scarce Ancistronycha abdominalis that does not occur in southern England, Podabrus alpinus which has a different shaped head and pronotum from the other species, and seven members of the Rhagonycha genus.

The most abundant, widespread and frequently recorded species in the genus, and indeed the family as a whole, is by far Rhagonycha fulva which, not surprisingly, is known as the Common Red Soldier Beetle.  They are a medium- sized, 8-10mm, pretty much unmistakable species with an all 'red' body apart from the broad black end of the elytra.

The other common species are Rhagonycha nigriventris (aka. R.limbata), Rhagonycha lignosa and Rhagonycha testacea. The remaining three are all scarce.

I've only seen one of these, Rhagonycha lignosa, which is a distinctive smallish species averaging around 7mm that can be easily identified by its black head and narrow black pronotum. The males have huge eyes as can be seen in the following photos.

The Malthininae subfamily comprises 16 species in two genera, Malthinus and Malthodes, all of which are small with shortened elytra that, to varying degrees, leave part of the abdomen and wings exposed. Most species are bluish- black or greyish-brown, many with yellow-tipped elytra. Although superficially similar, the shape of the head differs due to the location of the antennal sockets, which are slightly more distanced from the eyes in Malthinus than in Malthodes, such that when viewed from above the head looks wider at the front compared with the more rounded shape of Malthodes. The four Malthinus species can usually be separated with care, but distinguishing Malthodes for official recording purposes can only be reliably achieved by carefully examining the considerably modified terminal abdominal segments of the males.

Malthinus seriepunctatus is one of the smallest species with a body length of only 4-5mm. The head is yellowish- orange at the front and black at the back from behind the eyes that gives it a Y-shaped appearance when viewed from above. The pronotum is yellow with a variable dark 'hour-glass' shaped mark, which can be either well-defined or so narrow at the centre that it looks more like two separate blotches. The scutellum is black at the base, but yellowish at the apex, and the elytra are greyish-brown, typically darkening just before the yellow apices. There are a couple of other similarly marked species in the genus, but they can usually be separated with care.

Malthodes dispar is a tiny, dark-coloured, wet woodland beetle that despite being widespread is infrequently recorded. This could possibly be down to the fact that there does not appear to be any official descriptive information for the species other than the basal segments of the antennae are a reddish or yellowish colour, which is an important feature when trying to distinguish it from some other members of the genus. Unlike the previous species where the individual featured below quickly disappeared, the little Malthodes dispar I found just an hour or so later was very relaxed, which allowed me to get the shot with my thumb in it as this is the best way to get an indication of their size.    

Malthodes marginatus is a small 4-6mm species with a proportionally large head that can be much the same width, or even wider in the males, than the width of the small transverse pronotum. The forebody is black, but with variable and sometimes extensive orange-yellow pronotal margins. The elytra are dark brown with strongly contrasting yellow apices.

Updated, Jan.25 (v.3)