Eresus kollari (*)
Eresus kollari Rossi, 1846
* Aranea cinnaberinus Olivier, 1789 (misidentified)
* Rossi, F. W. 1846. Neue Arten von Arachniden des k. k. Museums, beschrieben und mit Bemerkungen über verwandte Formen begleitet. Naturw. Abh. Wien 1: 11-19. 
Eresus cinnaberinus (formerly Eresus niger), of the family Eresidae, is commonly called the Ladybird Spider. It is native to Europe.
The taxon "Eresus cinnaberinus" is considered a nomen dubium, the specimens having been divided into the species E. kollari, E. sandaliatus and E. moravicus. The three species differ in size, color pattern, shape of prosoma and copulatory organs, and habitat, with no morphologically intermediate forms. As eastern and western E. kollari are genetically different, with the eastern form likely a hybrid between "pure" E. kollari and E. moravicus, it is possible that later revisions will partition it into additional species.
Males are up to 11 mm long, females can reach up to 20 millimetres (0.79 in). Males have a black prosoma and a strikingly red opisthosoma with four black dots (sometimes with white lining), resembling a ladybug (or ladybird). The black legs have white stripes, the hind legs are partly red. Females are black with some white hairs, only the front is sometimes yellow.
This species can be found only in a "secret" half-acre patch of south-facing Dorset heathland in England. It prefers sunny, dry locations and is widely distributed in Central and Southern Europe.
These spiders live in up to 10 centimetres (3.9 in) long underground tubes with a diameter of about one centimeter. On top they are much wider and lined with cribellate silk. Many webs can usually be found in the same place, sometimes up to ten on a single square meter. E. cinnaberinus mainly catches millipedes and beetles. Males walk around during September, searching for females. If it finds one, it lives with the female in her tube, and they feed from the same web.
This spider is classified as endangered in Great Britain. It is given full protection under Schedule 5 of the Wildlife and Countryside Act 1981. In Germany it is also considered endangered.
Until the late 1920s the species was recorded from several sites in the English county of Dorset but was subsequently considered extinct in Britain. Rediscovered in 1979, it is known from only a single vulnerable, confirmed site in the town of Wareham. Other unconfirmed reportings have yet to be substantiated.
* Eresus cinnaberinus bifasciatus Ermolajev, 1937 (Russia)
1. ^ Rezac, Pekar & Johannesen 2008
* Population history of Eresus cinnaberinus (Araneae: Eresidae) colour variants at a putative species transition, abstract at PubMed
* Geographical distribution
Source: Wikipedia, Wikispecies: All text is available under the terms of the GNU Free Documentation License