Agrilus viridis

Book borer ( Agrilus viridis)

The book borer ( Agrilus viridis) is a beetle in the family Buprestidae ( Buprestidae ). The six to nine millimeters long, shiny metallic beetles is not easy to determine, because it occurs in color, size and hair with different variants, the other species of the genus Agrilus are similar. To what extent these variations must be considered as ecological races, subspecies or distinct species, is not yet clear.

In contrast to almost all beetle species splendor of the beech borer is not legally well protected in accordance with Federal Species Protection Ordinance. He is also guided in no Red List.

Remarks about the name

The first description of the species was made by Linnaeus in 1758 under the name Buprestis viridis. The description includes the formulation corpore viridi elongato (lat. with green elongated body ). This explains the species name viridis ( lat.grün ).

The genus Agrilus was erected by the Englishman Curtis 1825. He takes the name of Megerle. The declaration of the genus Agrilus name is uncertain. Schenkling provides its declaration ( AltGr. Άγρα Agra, hunting, prey, and είλω Eilo, gather ) with a question mark. A reference to characteristics of the species of the genus is not recognizable.

Description

The head is short, as in all species of the genus, as seen from above is about three times as wide as long. The eyes are large and cover almost the entire side of the head. Your posterior margin runs at a short distance parallel to the front edge of the pronotum (narrow cheeks). The eleven-membered sensors are from the fourth limb inwards extended ( cut ) and slightly higher than the lower edge of the eye turned in ( Fig. 4). When you book jewel beetles of the vertices is slightly domed, forehead furrowed flat and indistinct. The head is punctured wrinkled, and on the forehead and top of the head is the puncture elapsed längsrunzelig ( Fig. 3).

The pronotum bears as with all species of a "double " of the page. The lower than the actual margin keel- like elevation runs against the base of the neck shield to very closely next to this, forward the two edges apart. The keel -like raised pleat in the back corner of the pronotum is curved at book jewel beetle and not very pronounced (Fig. 3, green). Viewed from above the pronotum is rounded at its widest point is twice as wide as long. He narrowed in a straight line towards the base, the rear corners are not so extended. The oblique lateral impressions of the pronotum are not very pronounced. The tabs on the sides of the base, in which the bases of the elytra are fitted, are angular and not round (Fig. 3, yellow). The pronotum is curled querrunzelig and has an indistinct central furrow.

The scutellum is triangular and taper to a point as in the other species of the genus and has a cross keel (Figure 3, ocher ). In the book of the jewel beetle cross keel is prominent and backwards by a transverse groove (Fig. 3, white) accompanied.

The elytra each end rounded in itself and with a fine- toothed margins. At the base they each have a roundish impression laterally therefrom a sharp beulig vortretende shoulder area. In the middle part they are easy ausgerandet inside and let the side part of the background body uncovered. Then they taper evenly, the outer edge of the elytra but more so he seen from above disappears under the wing outline. Before the head of which he is, however, particularly in females, out sweeps and bounded from above again seen the wing-cover. Along the seam, the elytra are slightly indented, so that the seam seems applicable in the rear.

The chin appendage forechest is well developed, its anterior margin in the middle ausgerandet only flat, not angled cut (Figure 5, orange). To the rear, the front chest greatly prolonged ( Prosternalfortsatz, Figure 5, green). Between the spherical front of the hips Prosternalfortsatz parallel, then it tapers in the form of an acute triangle. In this case, it bridges the central chest, so that these will split. The tip of the Prosternalfortsatzes fits in a bulge of the lower breast (Fig. 5, ocher ). The rear hips are wide at the back and chest are strongly broadened outwards. You are caved for partially receiving the rear leg. The tarsi are all five-membered ( Tarsenformel 5-5-5 ), the first Tarsenglied of the hind leg is about as long as the following three Tarsenglieder together. The claws on the last Tarsenglied have at the base of a tooth that is short in the females, broad and blunt. In the males, the teeth of the claws on the front legs, however, are long and pointed. In contrast to Agrilus suvorovi the outer rear edges of the center and rear legs are not perforated.

Of the five sections on the underside of the abdomen ( sternite ), the first two are fused and form in Agrilus the widest and longest visible abdomen section. The following sternites narrowing a straight line, the last is rounded in the form of a circular cutout and has a groove on the edge. This is not emarginate inwardly at the beech borer.

Lower and upper sides are hairy only very sparsely and evenly and appear without increasing bald. Just next to the seam at which abut the elytra, longer in the back area light hair may occur.

Biology

The species lives in deciduous forests, where they can also be found at the forest edge and clearings. Even in parks and orchards it is found. The beetle sitting on bushes or different trees. The larvae develop in damaged hardwoods, especially willow, birch, beech, but also alder, hornbeam, hazel, maple, chestnut and lime trees, but not oak. Maybe it is, however, to different subspecies or even species.

Dissemination

The species is native to Central Europe, Russia, Asia Minor and North Africa.