House thorn fingers
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House thorn finger ( Cheiracanthium mildei ), female |
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| Scientific name | ||||||||||||
| Cheiracanthium mildei | ||||||||||||
| L. Koch , 1864 |
The house thorn finger ( Cheiracanthium mildei ), sometimes also called Mildes Dornfinger or Mildes Dornfingerspinne , is a spider from the family of the thorn finger spiders (Eutichuridae). The range of the species in Europe originally reached from the Mediterranean area to the Caucasus, in the last few decades it has penetrated north into the Rhine Valley . The house thorn finger was introduced to America in the 1940s and has been detected as far as the northern border of the United States in the past few decades.
features
Noticeable body features of the house thorn finger are the relatively long front legs and the uniform yellowish basic color. In contrast to the often coexisting wet nurse's thorn finger ( Cheiracanthium punctorium ) in its area of distribution, the house thorn finger has no green parts in its coloration and the spur on the male's globe is much smaller and inconspicuous.
The prosomal lengths of males are between 3.0 millimeters to 3.8 millimeters and in females 2.9 to 4.5 millimeters. Total body length is between 7 and 11 millimeters.
The species shows considerable sexual dimorphism , especially in terms of body length and thorns. In both sexes, the cephalothorax is about as long as the tibia of the last pair of legs, in the male it is almost as wide and in the female it is wider. The cephalothorax is rounded at the rear edge. It rises gradually from the rear edge in the male and briefly and steeply in the female and is arched between the second and third pair of legs. At the level of the eyes, the cephalothorax drops sharply again and is rounded at the front on the side. It has a pale brownish yellow, glossy color with darker side furrows and is thinly covered with adjacent hairs. Each eye sits in a black ring. The anterior median eyes are cloudy, the others light amber yellow. The front row of eyes is in a straight line and the distance between the front median eyes is shorter than the distance between the rear median eyes. The anterior median eyes are the largest. The side eyes sit on an elevation and the distance from the rear to the front side eyes is smaller than their diameter. Only the front side eyes are oval in contrast to the rest of the round eyes.
The chelicerae are brown-yellow and black-brown at the top. They are no longer than the patella of the first pair of legs, nor are they thicker than the fore legs. They are not arched in front, but sloping vertically from the cephalothorax. The legs have a grayish-brownish basic color.
The abdomen is arched up and gray-brown with yellowish spots, a tapering yellow spot begins at the base and tapers approximately in the middle of the abdomen. The abdomen has very little short hair and sporadic bristles. The spider has six brownish-gray spinnerets. The upper ones have a cylindrical shape, the lower ones a conical shape.
Way of life
Growing spiders live in webs of rest. These are retreat areas for the day that are not intended as traps. When hunting, the animals roam around at dusk and at night. The exact selection of prey is unknown. It has been observed that their prey animals include all sorts of small insects that they find on trees, bushes and shrubs, as well as eggs and larvae such as those of the moth . The life expectancy of the spider is one year.
Reproduction
After mating, the male dies very soon and the female goes on a more intensive search for food. It builds a protected brood web from leaves and spider silk and lays 30 to 48 eggs. She guards the cocoon until the young hatch. Then the mother dies. The juveniles spin winter webs on wilted leaves near the ground.
Surname
The generic name Cheiracanthium refers to the thorn-like process on the male's bulb (see k in the scheme). This extension is, however, a lot more inconspicuous in this species than in other representatives of the genus and shorter than the fourth link of the button. The spur is located between the two processes of the tibia (tibial apophyses). The species name mildei was given in honor of the botanist Julius Milde , who first discovered the spider in Meran and presented it to Ludwig Carl Christian Koch for identification.
Web links
House thorn fingers in the World Spider Catalog
Individual evidence
- ↑ a b c d Niederösterreichisches Landesmuseum, Dornfinger - a spider becomes a media star (PDF; 2.8 MB), accessed March 7, 2011
- ↑ a b c Nentwig W, Blick T, Gloor D, Hänggi A, Kropf C: Spinnen Europa. www.araneae.unibe.ch. Version 11.2016.
- ↑ a b c Bugguide, Cheiracanthium mildei , accessed October 26, 2008
- ↑ The Nearctic Spider Database, Cheiracanthium mildei L. Koch, 1864 ( Memento of the original from October 29, 2008 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , accessed October 26, 2008
- ↑ a b c d e Ludwig Carl Christian Koch , The European species of the arachnid genus Cheiracanthium. Dep. Naturh. Ges. Nürnberg 14 [(3) 1]: 137-162. 1864.
