Cyrtarachne


Cyrtarachne is a genus of orb-weaver spiders first described by Tamerlan Thorell in 1868.

Life style

Cyrtarachne construct “spanning thread-webs”, a basic orb-web, but the web diameter, sticky spiral spacing and viscid thread diameter differ from that of typical orb-webs.
The viscid threads are studded with large droplets. Each of the short threads between the radii is known as a spanning thread, and is unique in that it breaks when prey comes into contact with it. The prey flies into the web, gets stuck to a viscid thread, the thread breaks, and the spider pulls the prey up to the hub of the web to feed. During the day the spider rests on close-by vegetation mimicking bird-droppings.

Description

Females are 5–8 mm in total length, while males are 2–3 mm. The female carapace is brown and shiny, convex and simple. The ocular quadrangle is slightly wider than long, with lateral eyes contiguous. The abdomen is large and triangular, wider than long, decorated with horizontal bands of white and brown centrally, with paired sigilla. The dorsum is shiny, appearing hard and shell-like. The legs are short with leathery integument and coloured bands and patches. Males differ from females and are much smaller.

Species

, this genus includes 54 species and two subspecies:Cyrtarachne akirai Tanikawa, 2013 – China, Korea, Taiwan, JapanCyrtarachne avimerdaria Tikader, 1963IndiaCyrtarachne bengalensis Tikader, 1961 – India, ChinaCyrtarachne bicolor Thorell, 1898 – MyanmarCyrtarachne bigibbosa Simon, 1907São Tomé and Príncipe, Equatorial Guinea Cyrtarachne bilunulata Thorell, 1899 – CameroonCyrtarachne biswajiti Biswas & Raychaudhuri, 2020 – BangladeshCyrtarachne biswamoyi Tikader, 1961 – IndiaCyrtarachne bufo – China, Korea, JapanCyrtarachne cingulata Thorell, 1895 – MyanmarCyrtarachne conica O. Pickard-Cambridge, 1901 – SingaporeCyrtarachne dimidiata Thorell, 1895 – MyanmarCyrtarachne fangchengensis Yin & Zhao, 1994 – ChinaCyrtarachne finniganae Lessert, 1936MozambiqueCyrtarachne flavopicta Thorell, 1899 – Cameroon, Equatorial GuineaCyrtarachne friederici Strand, 1911 – New GuineaCyrtarachne gibbifera Simon, 1899 – Indonesia Cyrtarachne gilva Yin & Zhao, 1994 – ChinaCyrtarachne grubeiMauritius Cyrtarachne guttigera Simon, 1909 – VietnamCyrtarachne heminaria Simon, 1909 – VietnamCyrtarachne histrionica Thorell, 1898 – MyanmarCyrtarachne hubeiensis Yin & Zhao, 1994 – ChinaCyrtarachne ignava Thorell, 1895 – MyanmarCyrtarachne inaequalis Thorell, 1895 – India, China, Korea, MyanmarCyrtarachne invenusta Thorell, 1891 – India Cyrtarachne ixoidesMediterranean, Caucasus, South Africa, MadagascarCyrtarachne jucunda Tanikawa, 2013 – JapanCyrtarachne kaikobadi Biswas & Raychaudhuri, 2025 – BangladeshCyrtarachne lactea Pocock, 1898 – East AfricaCyrtarachne laevis Thorell, 1877 – Indonesia Cyrtarachne latifrons Hogg, 1900 – Australia