Stegnocephala chalcites (Suffrian, 1863)

General description: 

Blue body; the head, roots of antennae, the non-punctured pronotum, shoulder blades and hips all red; dense punctures and stripes with flat, finely wrinkled interspaces. [Translated from the original German in Suffrian, 1863].


The current S. chalcites is a species that finds difficulty in falling into our system of classification, since it can almost equally likely be placed in its current genus and group as in that of the Monachus, or even as a bridge between the two. The Monachus, under which this species would be known by M. bicolor Fab., shows a habitual similarity with its relatives: relatively short antennae that are wider at the top and the short, by no means extended front edge of the prosternum. On the other hand, the straight-cut rather than arch-like, and in the middle, curve-tipped, hind edge of the pronotum distances this species from the Monachus, and the wide, leaf-shaped teeth behind the claws renders it undoubtedly closer to the Cryptocephalines. Because I see no substantial use in basing an entire transitional genus on a single species, I prefer for now to establish this species as an aberrant form until the discovery of a greater number of specimens in both sexes and perhaps also other closely related species provides us a firmer decision as to its proper systematic place.

As a species of the third Rotte, this beetle is closest to the smaller specimens of S. perplexa, differing from the latter not only through its color, but also through its longer contour. The head is flat, slightly protruding between the eyeholes. The frons is softly pressed down, so that the lower edge and the sides step out as light edges. The far-extended, moderately grooved eyes that are somewhat pressed together at the top are black. The rest of the head is mirror-like glossy red with somewhat darker mouthparts. With one of the available species, the forehead is pressed down along its length. The antennae are not half the length of the body. The root segment is thin, a little curved, about three times longer than wide. The second segment is elliptical, about three times shorter than and half as wide as the first. The following two segments are thin and almost equally wide. The fifth is slightly wider at the top. The upper segments are expanded towards the inside in wide triangles, with round edges, and pressed together. The last segment ends in a triangular protrusion. All segments, from the third onwards, are the same length and about 1.5 as long as the second. The color of the five lower segments are bright, transparent yellow-red; the fifth bears a brown tip. The upper segments are black and covered with fine hair. The pronotum is not half as long as it is wide at the back; it arches slightly in the latter portion, and its front portion, almost 2/3 of its length, curves backwards, reaching the deeply withdrawn, almost rectangular front edges, where it is pressed together. The sides are finely edged and pressed together in the front in wide arches. The short hind edges extend into wide sharp tips. The hind edge is only lightly hollowed out on either side, finely serrated, with a short, wide, doubly edged mid-tip. The surfaces in front of the middle of the hind edge are narrowly indented across and not notably punctured, bearing massive, glossy interspaces, a uniform red, and a fine black edge at the back. The scutellum is triangular and dark blue, almost twice as long as it is wide, cut off abruptly at the back and slightly rising upwards, with clear front dimples. The front portion of the elytra are notably wider than the pronotum, about 1/4 longer than they are wide. Behind the shoulders, they curve out again, and are rounded off short and egg-shaped at the back. Behind the sharp root edges, the elytra are pressed down across the deeply engraved front ends of the puncture-stripes. The elytra rise in slight humps around the scutellum-tip, and from this hump, fall gradually along a flat seam gradually to the [end] tip. The shoulder humps form sturdy protrusions; they are supported in the inside by an indent that meets the front end of the fifth stripe. The side flanks are wide, but not deeply pulled down. The puncture-stripes are regular and clear until the ends. Besides the front ends of the five upper stripes, the ninth is also deeply indented. The interspaces are wide, flat, crowdedly and finely punctured in wrinkles on the outside, after which they are only moderately glossy. The ninth interspace rises slightly in the shape of a rib. The species bears a beautiful iron-blue color. With one of the available specimens, the middle of the back and the scutellum are enclosed with a murky, metallic, dark streak. The pygidium is black, coarsely and wrinkly punctured, and almost cut off abruptly at the bottom. The undersides are punctured in finer wrinkles. The abdomen and the parapleura are thinly haired. The abdomen and hind chest are blue-black. Shoulder blades, mid and front chest are rusty red. The front chest is wider than it is long, bulges upwards in the middle, has short front edges that bend downwards, and is indented at the back. The hind edge itself is straight, curved in the middle into a tip, with short triangular, protruding hind edges. The legs are blue-black with tanned foot segments. The hips and the front legs, as well as the upper half of the thighs, are red. The last segment of the female has a deep, rounded mirror-like glossy groove that absent in the male.

[Translated from the original German in Suffrian, 1863].

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith