''Caerostris'', sometimes called bark spiders, is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of orb-weaver spiders first described by

Tamerlan Thorell Tord Tamerlan Teodor Thorell (3 May 1830 – 22 December 1901) was a Sweden, Swedish arachnologist. Thorell studied spiders with Giacomo Doria at the Museo Civico di Storia Naturale de Genoa. He corresponded with other arachnologists, such as Oc ...

in 1868. Most species are found in south eastern Africa and neighboring

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

Taxonomy

The genus ''Caerostris'' was erected in 1868 by

with the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

being ''Epeira mitralis'' Vinson, 1863, which Thorell transferred to ''Caerostris mitralis''. Up to 2009, only 11 species had been described. A further species, ''C. darwini'', was described in 2010, and six more species in 2015. Two of the "species", ''C. sexcuspidata'' and ''C. sumatrana'', will probably need to be divided further to produce genetically uniform species. A molecular phylogenetic study of 12 of the species of ''Caerostris'' produced the phylogenetic tree shown below, showing that the African and Madagascan species form a

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

group.

Species

it contains eighteen species: *'' Caerostris almae'' Gregorič, 2015 – Madagascar *'' Caerostris bojani'' Gregorič, 2015 – Madagascar *'' Caerostris corticosa'' Pocock, 1902 – South Africa *'' Caerostris cowani'' Butler, 1882 – Madagascar *'' Caerostris darwini'' Kuntner & Agnarsson, 2010 – Madagascar *'' Caerostris ecclesiigera'' Butler, 1882 – Madagascar *'' Caerostris extrusa'' Butler, 1882 – Madagascar *'' Caerostris hirsuta'' (Simon, 1895) – Madagascar *'' Caerostris indica'' Strand, 1915 – Myanmar *'' Caerostris linnaeus'' Gregorič, 2015 – Mozambique *'' Caerostris mayottensis'' Grasshoff, 1984 – Comoros, Mayotte *'' Caerostris mitralis'' (Vinson, 1863) – Central Africa, Madagascar *'' Caerostris pero'' Gregorič, 2015 – Madagascar *'' Caerostris sexcuspidata'' (Fabricius, 1793) – Africa, Madagascar, Comoros, Seychelles (Aldabra) *'' Caerostris sumatrana'' Strand, 1915 – India to China, Borneo *'' Caerostris tinamaze'' Gregorič, 2015 – South Africa *'' Caerostris vicina'' (Blackwall, 1866) – Central, Southern Africa *'' Caerostris wallacei'' Gregorič, Blackledge, Agnarsson & Kuntner, 2015 – Madagascar

References

Spiders of Africa Spiders of Asia Araneomorphae genera Taxa named by Tamerlan Thorell {{Araneidae-stub