Cyclocosmia Explained

Cyclocosmia is a genus of mygalomorph trapdoor spiders in the family Halonoproctidae, first described by Anton Ausserer in 1871.^[1] Originally placed with the Ctenizidae, when the family split in 2018, this genus was placed with the Halonoproctidae as the type genus.^[2] The name is derived from the Greek "kyklos" (Greek, Ancient (to 1453);: κυκλος), meaning "circle", and "kosmeo" (Greek, Ancient (to 1453);: κοσμεω), meaning "to adorn".^[3]

Description

C. ricketti females are long, with a disk diameter of . Their burrows are 7to deep, and only the bottom portion of the burrow is silk lined.^[4]

These are trapdoor spiders, whose species are distinguished from each other by the pattern of the abdominal disk, the number of hairs on its seam, and the shape of the spermathecae. They have abdomens that are abruptly truncated, ending in a hardened disc that is strengthened by a system of ribs and grooves. They use this to clog the entrance of their burrows when threatened,^[5] a phenomenon called phragmosis. The disks have strong spines around the edge, and they each have four spinnerets just anterior to it. The posterior, retractable spinnerets are particularly large.

Species

it contains ten species:^[6]

• Cyclocosmia lannaensis Schwendinger, 2005 – China, Thailand
• Cyclocosmia latusicosta Zhu, Zhang & Zhang, 2006 – China, Vietnam
• Cyclocosmia liui Xu, Xu & Li, 2017 – China
• Cyclocosmia loricata (C. L. Koch, 1842) – Mexico
• Cyclocosmia ricketti (Pocock, 1901) – China
• Cyclocosmia siamensis Schwendinger, 2005 – Thailand, Laos
• Cyclocosmia sublatusicosta Yu & Zhang, 2018 – China
• Cyclocosmia subricketti Yu & Zhang, 2018 – China
• Cyclocosmia torreya Gertsch & Platnick, 1975 – USA
• Cyclocosmia truncata (Hentz, 1841) (type) – USA

Further reading

• (2005): Two new Cyclocosmia (Araneae: Ctenizidae) from Thailand. Revue Suisse de Zoologie 112(1): 225-252

External links

• Cyclocosmia at Bugguide.net
• Cyclocosmia close up

Notes and References

1. Ausserer. A.. 1871. Beiträge zur Kenntniss der Arachniden-Familie der Territelariae Thorell (Mygalidae Autor).. Verhandlungen der Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft in Wien. 117–224. 21.
2. Godwin. R. L.. etal. 2018. Phylogeny of a cosmopolitan family of morphologically conserved trapdoor spiders (Mygalomorphae, Ctenizidae) using Anchored Hybrid Enrichment, with a description of the family, Halonoproctidae Pocock 1901. Molecular Phylogenetics and Evolution. 126. 307. 10.1016/j.ympev.2018.04.008. 29656103. 4890400.
3. Web site: Genus Cyclocosmia. BugGuide. 2019-05-27.
4. Murphy. Frances. Murphy. John. 2000. An Introduction to the Spiders of South East Asia. Malaysian Nature Society. Kuala Lumpur.
5. Zhu. M.S.. Zhang. J.X. Zhang. F.. 2006. Rare spiders of the genus Cyclocosmia (Arachnida: Araneae: Ctenizidae) from tropical and subtropical China. The Raffles Bulletin of Zoology. 54. 1. 119–124. 2007-08-17. 2007-08-11. https://web.archive.org/web/20070811074158/http://rmbr.nus.edu.sg/rbz/biblio/54/54rbz119-124.pdf. dead.
6. Gen. Cyclocosmia Ausserer, 1871. World Spider Catalog Version 20.0. 2019-05-27. 2019. Natural History Museum Bern. 10.24436/2.