Dendarus coarcticollis

Group of Dendarus coarcticollis in rotten wood

Dendarus coarcticollis, previously Dendarus tristis, is a beetle of the family of darkling beetles. The genus Dendarus is represented in Europe with 54 species,

Remarks about the name

The beetle was described in the traditional opinion for the first time under the name Dendarus tristis Laporte de Castelnau 1840. Regarding the name tristis to Laporte relates to autumn. The genus name Dendarus he takes over from the collection catalogs of Dejean. This tristis (lat. sad, gloomy ) stands for the dark color of the beetle, the derivation of Déndarus remains unknown Schenkling.

Although this description by Laporte contains nothing contradictory to the one presented here beetle, but noted a conspicuous feature ( shape of the pronotum ) is not. It is particularly significant that it is contrary to the type described by autumn as Tenebrio tristis 1797, whose species name tristis Laporte takes over. A complicating factor is that a third beetles of the family of the darkling beetle Rossi gets the style name tristis and appears in later literature and in combination Dendarus tristis Rossi. Edited Mulsant 1854 tenebrionids as Latigènes with detailed identification keys. The beetle described here he gives the names of species coarcticollis and assigns it to the only ( French ) species of the genus Pandarus. In the list of synonyms he explicitly mentions that it is the beetle Dendarus tristis Laporte 1840 .. The name part coarcticollis (Latin coarcticóllis constricted pronotum ) designate precisely the peculiarity of the beetle, a large part of the description Mulsants is also the form dedicated to the pronotum. The genus Pandarus shall be finalized by Mulsant. The genus name was adopted from Megerle. After Mulsant he is AltGr from. Πάνδαρος derived. This is the name of several characters from Greek mythology. He takes to the names change from Dendarus after Pandarus how he can be observed in the catalogs of Dejean, Pandarus is a later synonym of Dendarus.

In one of his time- relevant German- determination work is of the opinion, however, in 1877, the new name by Mulsant is not scientifically justified. In addition, the genus Pandarus Mulsant is again replaced by Dendarus and split into six subgenera. The species described here is placed in the subgenus Dendarus and gets back the name Dendarus tristis or Dendarus ( Dendarus ) tristis. In later German koleopterologischen works the way does not appear, because their range is outside of Central Europe. Among the currently valid International rules for zoological nomenclature, however, the name Dendarus tristis is scientifically unavailable name. Under the still valid assignment to the genus Dendarus is now called the nature Dendarus coarcticollis.

Description of the beetle

The stretched to oval, only slightly curved beetle is twelve to thirteen millimeters long with a width of about six millimeters. It is matte black, but occasionally but by a bright tires dull gray.

The head is in the eyes a little wider than behind it. He is very weak in the front area, dotted rough on the forehead, the points flow partially to Längsrunzeln. The eleven-membered cord-like sensors barely reach the posterior margin of the neck plate. They are black at the base, yellowish brown on top. The kidney-shaped eyes are set on the side of head. Their vertical dimension is much larger than the horizontal. They are cut in front but little from the long cheeks.

The pronotum extends fairly evenly past the half, then it narrows abruptly rounded outward to the fourth -fifth, in the last fifth of its length extending the right and left sides almost parallel. On the front and back of the neck plate is slightly curved outward. The rear corners are pulled backwards and come to rest in a small cutout on the shoulder area of the wing-cover. Before each wing-cover the pronotum is slightly cut. He follows closely the elytra basis. At the sides it is edged, the edge disappears forward, backward it is wider and higher. The pronotum is coarsely dotted, the dots melt mainly laterally into predominantly longitudinally aligned wrinkles. In the center runs an especially among the females hardly noticeable shortened at both ends of the longitudinal groove ( Fig. 3). The scutellum is small.

The elytra are as wide as the pronotum base to the base. They appear streaked through furrowed slightly recessed longitudinal rows of dots. The intervals between these point streaks are dotted very dense and somewhat wrinkled. The intervals lying near the elytra are almost flat seam, the intervals lying further out are moderately arched backwards all intervals are striking. The seventh interval, which originates on the shoulder is raised like a strip along the entire length and joins at the end of the wing with the third interval. The under whipped part of the elytra ( Epipleuren ) is relatively narrow and tapers to the rear.

Between the front waist rearwardly extending Prosternalfortsatz has a distinct longitudinal groove. Front and middle legs wearing five-membered tarsi, the male they are widened. The Hintertarsen are four members. The first Tarsenglied the Hintertarsen is about the same as the jaw member. In the male, the rails of the front legs are curved and end considerably wider than the central rails. The center rails support a small peak before the end. The first three Tarsenglieder of the anterior and middle pair of legs are hairy at hand like a brush. In females, the front legs are narrower and less curved. The first three Tarsenglieder of the anterior and middle pair of legs are also hairy, but the bristle pad are separated into two halves ( in Figure 4 at the upper Mitteltarsus recognizable as females ).

Biology

The species occurs on dry to very dry sites before. In a study concerning the decrease of biodiversity in Rome is found that Dendarus coarcticollis could keep there unlike other Tenebrionidae, because he lives in wood ( in the large city park ). However, it is probably because Dendarus tristis Rossi. In a calendar about the seasonal first occurrence of frequent animal and plant species at Aix in the method known under stones in February and the end of May. Mulsant mentioned that the live beetle can cause according to his will a frosted appearance ( Taxobild, Figure 3).

Dissemination

In the early literature as a distribution area south of France and northern Italy (South Tyrol ) is specified. In addition, Corsica and Hungary may be called.