Cychrus spinicollis

Cychrus spinicollis

Cychrus spinicollis is a beetle of the family of ground beetles of the genus and blade runner. Form The blade runner is an easily recognizable species. It contains 84 species, fourteen of which are found in Europe worldwide. The type Cychrus spinicollis occurs only on the Iberian Peninsula and includes two subspecies, the nominate next Cychrus spinicollis spinicollis nor the subspecies Cychrus spinicollis ibericus.

Remarks about the name

The species was first described in 1857 by Dufour. Dufour begins the French part of his description with the words: " Ce Cychrus a la forme et la grandeur du rostratus, dont on le distingue à l'instant par l' épine aigue et bien détachée angles of the prothorax Posterieurs you " (French: This Cychrus has the shape and size of rostratus, from which one can distinguish him immediately by the sharp spike which projects from the rear corners of the neck plate ). This explains the species name spinicollis from Latin spina, thorn and collum, neck, neck plate. The corresponding figure for the drawing is accidentally called with Cychrus acuticollis instead Cychrus spinicollis. The name of the genus is Cychrus AltGr. Κυχρεύς Kychréus, the mythological name of the son of Poseidon and Salamis derived.

Description of the beetle

The beetle shows the typical shape of a blade runner with a long head, very slender neck shield and long walking legs.

The slim head is punctured and wrinkled very fine and barely perceptible. The mouthparts with long mandibles pointing forward. The upper lip (right green in Figure 5) cut deeply bilobed. The maxilla ( Fig. 5, right in blue) are long and slender and end in a claw-like tip. Among them sit on the inside of two similarly shaped sharp teeth. The mandible wear four-membered jaw switch ( Fig. 1, right in red) with a very small first and very long third term. The external loading of the mandible is transformed into a two-tier switch, wherein the base member so small that end link but large and razor shaped with introspective inside edge ( in Fig 3 translucent thin at full magnification at the lowest level among the pine trees in the front area well to recognize ). The labial palpi (right yellow in Figure 5) has a tripartite with a very small base member. The end members of the lips and jaw buttons are strikingly large and beilförmig, thereby undermined scoop or spoon-shaped at the bottom. The eleven-membered antennae are filiform and hairy from the fourth limb very short gray.

The narrow, heart-shaped pronotum is considerably gross wrinkled punctured than the head. It has a deep depressed center line, which is usually formed over the entire length of the throat plate. The rear corners are drawn out to a long pin which is bent upwards (Fig. 1).

The elytra are fused together. Outside they are along a line ( in Figure 4, right ) under beaten by the shoulder almost to the end of elytra and disintegrate so in a dorsal and a folded under part. The dorsal part carries three rows of longitudinal surveys with constant distance ( chain strips, in Figure 4, 1st row green tinted). Between the chain strips the elytra show a fine structure from running into each other elevations, which appear wrinkled in certain lighting. Graells one of these three rows as 1, 3, and 5 of five rows, where the elevations are formed higher than in the intervening 2nd and 5th row ( seen in Figure 3). The side- lying, slightly below beaten, roughly triangular area of ​​the wing-cover is like the intervals of the top structured.

On the underside of the breast is less coarse, but distinctly punctate. The abdomen is roughly punctured at the sides, smooth against the middle.

The legs are black, the rails for the most part and the tarsi brightened sometimes yellow-brown.

Larva

The larvae of the genus Cychrus have a broad, assel shaped physique. The larvae of Cychrus spinicollis are flat, about the middle of the abdomen at the widest, and the transition from chest to abdomen segments segments is fluid. Upper hand, they are dark brown, lighter on the underside.

The head is square to roundish and not issued by a neck from the chest. The first instar larvae are located on the front two teeth-like growths that serve the rupture of the egg membrane. The front edge of the head is increased between the Einlenkungen the jaw on the sides and in the middle. On the side elevations outside each sits a large pore point where arises a long bristle. Near here is a group of small pores. Other small pores and hairs are found only sporadically. The face plate extends no visible seam to the posterior border of the head capsule.

The long antennae are four members. The small base member is thickest and is approximately twice as long as wide. It carries two points pores and a bristle. The second antennal segment is the longest. It is fitted on the back side with numerous points and bristle hair. The third member is shorter and thinner. On it, more pores and hair are also distributed. The end member is to thinnest and about as long as the base member. It is pointed and animal that does a group of hairs of different lengths, two of them long. Behind the inwardness of the sensors are located on each side six simple eyes that are arranged in two groups of three eyes. The upper jaw is attached to the base with a width at the inner edge of the inwardly projecting denticulate refining surface, which is extended at the front corner of the inner edge in a slightly curved tooth. On the surface it is equipped with numerous small short spines. Also, the front part of the mandible is very finely denticulate on the inner edge. About half way up there is a single hair. In addition, sits a larger pore, another major along with a group of smaller pores located at the base. The basal joint of the lower jaw ( Cardo ) is very small and is wearing a bristle-bearing pore. The following member ( Stipes ) is large and well developed. It is approximately rectangular with six large hairs on the outer edge and an array of numerous small hairs on the inside. The area between the hair and the hair set outside the inside area near the base is wide and becomes narrower to the apical end. In this area there are small pores, which are numerous at the same density towards the base. On the Stipes sits inside the very small lobed ausbegildete lacinia bearing a single hair at the end. Outwardly, sitting next to the two-tier Galea. The larger base member carries two hairs in between a pore. The spindle-shaped end member shows no auffällitgen structures. In addition to the galea to the outside of the jaws is hinged button. He is four members, the members are increasingly longer and thinner outwards. The density of the pores and the hair decreases outwards. The first and second members still bear relatively large pores and hair. The third term has two hairs and two pores, the bald last link has only two pores. The lower lip bears two bipartite labial palpi. The two terms are approximately equal, the outer ends rounded. The first term contributes five hairs, the second three large pores.

The first thoracic segment is the longest and narrowest, the third thoracic segment is the shortest and widest. The back panels of the chest section are divided into two and finely punctured by a longitudinal line. They widen towards the rear, front and rear corners are heavily rounded. The Intersegmentalhäute connecting the chest sections that carry groups of bristle hair. The three pairs of legs differ essentially only by the size, with the front legs, the hind legs are greatest at the smallest. They consist of the parts of the hip, Hüftring, leg, rail, and eingliedrigem foot. This carries a pair of two equally -built simple weakly curved claws. The links of the legs are hand bristly hairy, with a single hair on the outer end of the leg ring really stand out for its size.

The abdomen consists of ten members. These are from the first to fourth generation little wider and from the fifth element to the rear increasingly smaller. The first seven segments differ when viewed from above only slightly from the third thoracic segment, the eighth is deeply indented on posterior margin, ninth in supervision has approximately the shape of a circular sector and adapts into the cutout of the eighth segment. The tenth and final member sits as a small cone on the ninth segment. The dorsal plates of the abdomen are dotted bald and fine. Show apart from the last two such as the thoracic segments significant longitudinal centerline. On the hind angles they wear flat increases and reach there the following sternite. The last abdominal segment is very small and conical tapered. On the back side it carries many different long hair, ventral to sit on each side four hairs. On the underside of the abdomen are located in the anterior segments of five laterally adjacent separate plates. From the fourth abdominal segment, the three central plates are fused to a so three plates are available. In the ninth segment only a tummy plate is available. In addition, the ninth dorsal segment wearing a short pair Appendix ( Urogomphi ), which is above the tenth abdominal segment and is much shorter than this.

Biology

In a comparison of nineteen different vegetation types Cychrus spinicollis was found with one exception only in forests. In comparison with riverine forests, mixed forests, pine forests and eucalyptus forests, the animals were caught almost exclusively in mixed forests. In another study with five forest types, the species was found exclusively in Buchenwald. When comparing the frequency of the beetle on forest edges of oak forest and forest edges of Buchenwald in northern Spain, the species was caught only in Buchenwald, as compared woods edge, 50 meters and 100 meters from the edge clearly most 100 m deep in the forest. The species is classified as residents of moist forests. They can be found there often at the entrance of caves and caverns, mainly in autumn and winter. On the occasion of the description of the larvae gesammtelte copies were always found near the shore in the moist deciduous forests, where holly, birch and haws were the most common tree species in the understory occurred the blueberry.

Larva and Imago feed on snails. The mouthparts of beetles allow penetration into snail shells and the scraping of the prey that folded under side of the wing covers to prevent sticking of the spiracles through the slime of snails.

The beetles reproduce in the fall and in November are clearly the most common. The first larvae of the first instar larvae are found in December, but the maximum of larvae finds is from February to April. Larvae of the third and last stage can be found in May. This suggests a long pupal period. The beetles of the new generation appear in late spring or summer.