''Eresus'', also called ladybird spiders, is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of velvet spiders (family Eresidae) that was first described by

Charles Athanase Walckenaer Baron Charles Athanase Walckenaer (25 December 1771 – 28 April 1852) was a French civil servant and scientist. Biography Walckenaer was born in Paris and studied at the universities of Oxford and Glasgow. In 1793 he was appointed head of t ...

in 1805. Members of the genus formerly called '' Eresus cinnaberinus'' or ''Eresus niger'' are now placed in one of three species: '' Eresus kollari'', '' Eresus sandaliatus'' and '' Eresus moravicus''.

Description

They resemble both

jumping spider Jumping spiders are a group of spiders that constitute the family Salticidae. As of 2019, this family contained over 600 described genera and over 6,000 described species, making it the largest family of spiders at 13% of all species. Jumping spi ...

s and the spiders in the

Palpimanidae Palpimanidae, also known as palp-footed spiders, is a family of araneomorph spiders first described by Tamerlan Thorell in 1890. They are widely distributed throughout the tropical and subtropical regions of the world, the Mediterranean and one in ...

, as their body shapes are similar and their body is velvety. Males of this genus have a red abdomen with black spotting, usually sporting 4 black spots. The rest of the body is usually black, with some reddish or white areas. Females of this genus usually have dull colors, in grey, brown or black tones. For most individuals, the full body length reaches 8.5 to 20mm, with a distinct prosomal length of 3.6 to 6.1 mm. In some species, the females have some yellow coloration, though they are still significantly duller than the males.

Identification

Males of this genus can usually be distinguished by their unique

abdominal The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso ...

pattern. Which in the lateral areas has two pairs of black patches which is surrounded by some reddish coloration. Sometimes they also have an extra pair. Females are harder to distinguish, with a species specific dedicated identification section being needed.

Distribution

They are found in

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an ...

, and

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

, usually in non-forested warm and dry habitats. Their life cycle is completed in 3–4 years, after they undergo dispersion and reach a juvenile state and turn into predators. Some species build a vertical

burrow An Eastern chipmunk at the entrance of its burrow A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of locomotion. Burrows provide a form of s ...

which is lined with silk, the opening being camouflaged with a silken sheet of debris. While some species don't build a burrow and just make their tubes under stones.

Species

it contains twenty-four species: *'' Eresus adaleari'' Zamani & Szűts, 2020 - Iran *'' Eresus albopictus'' Simon, 1873 – Morocco, Algeria *'' Eresus bifasciatus'' Ermolajev, 1937 – Russia (South Siberia) *'' Eresus crassitibialis'' Wunderlich, 1987 – Canary Is. *'' Eresus granosus'' Simon, 1895 – Russia (West Siberia), China *'' Eresus hermani'' Kovács, Prazsák, Eichardt, Vári & Gyurkovics, 2015 – Hungary, Slovakiahttp://saras-arachno.sk/saras_pavuk-check.htm *'' Eresus kollari'' Rossi, 1846 – Europe, Turkey, Caucasus, Russia (Europe to Far East), Iran, Central Asia **'' Eresus k. frontalis'' Latreille, 1819 – Spain **'' Eresus k. ignicomis'' Simon, 1914 – France (Corsica) **'' Eresus k. latefasciatus'' Simon, 1911 – Algeria **'' Eresus k. tricolor'' Simon, 1873 – France (Corsica) *'' Eresus lavrosiae'' Mcheidze, 1997 – Georgia *'' Eresus lishizheni'' 2021 - China *'' Eresus moravicus'' Řezáč, 2008 – Austria, Hungary, Czech Rep., Slovakia, Albania *'' Eresus pharaonis'' Walckenaer, 1837 – Egypt *'' Eresus robustus'' Franganillo, 1918 – Spain *'' Eresus rotundiceps'' Simon, 1873 – Ukraine, Turkmenistan *'' Eresus ruficapillus'' C. L. Koch, 1846 – Italy (Sicily) *'' Eresus sandaliatus'' (Martini & Goeze, 1778) – Europe *'' Eresus sedilloti'' Simon, 1881 – Portugal, Spain *'' Eresus solitarius'' Simon, 1873 – Mediterranean *'' Eresus tristis'' Kroneberg, 1875 - Kazakhstan *'' Eresus walckenaeri'' Brullé, 1832 – Mediterranean **'' Eresus w. moerens'' C. L. Koch, 1846 – Afghanistan

References

External links

* Spiders of Europe Araneomorphae genera Eresidae Spiders of Africa Spiders of Asia Taxa named by Charles Athanase Walckenaer {{Araneomorphae-stub