Uloborus

Uloborus is a spider genus in the family Uloboridae with 79 described species.

Distribution

Most species occur in the tropics and subtropics, with only a few species in northern America and Europe.

Life style

Uloborus spiders build small orb-webs with cribellate silk. The hub is often meshed or strengthened with a stabilimentum that varies in shape, with the most common configuration being a linear silk band.
The web is usually tugged forcefully as the spider approaches the prey to locate it and entangle it further. The first, and to a lesser extent the second legs, are used for tugging. The front legs are used to lightly touch the prey. Hanging from the first and second legs, the spider uses the fourth pair of legs to throw silk onto the prey to subdue it. The spider faces away from the prey while wrapping it. The silk entangles the thrashing limbs, preventing injury to the spider. They prey on a variety of flying insects.
Uloborids lack venom glands and use digestive enzymes that are poured onto the prey to kill them. The silk wrapped around the prey becomes transparent after absorbing some of the enzymes. Spiders are frequently seen with large prey masses in their mouths.

Description

The chelicerae of these cribellate spiders are robust, but, like all Uloboridae, there are no venom glands. Eight small eyes are present.
The carapace is pear-shaped. The cephalic and thoracic regions of females are level, with the thoracic depression being a shallow pit. The cephalic region of males is curved slightly downward from the thoracic depression. The eight eyes are arranged in two rows and both eye rows are recurved.
The abdomen is longer than wide with 1-2 humps. The colour of the body is usually dull shades of cream, grey or brown, usually with markings.
Legs I and IV are longer than the other legs. The tibiae I have a brush of long setae in some species.

Species

, this genus includes 72 species and five subspecies:Uloborus albescens O. Pickard-Cambridge, 1885 – Pakistan, IndiaUloborus albofasciatus Chrysanthus, 1967 – New GuineaUloborus albolineatus Mello-Leitão, 1941 – ArgentinaUloborus ater Mello-Leitão, 1917 – BrazilUloborus aureus Vinson, 1863 – MadagascarUloborus barbipes L. Koch, 1872 – Australia Uloborus berlandi Roewer, 1951 – GuineaUloborus biconicus Yin & Hu, 2012 – ChinaUloborus bigibbosus Simon, 1905 – IndiaUloborus bispiralis Opell, 1982 – New GuineaUloborus campestratus Simon, 1893 – USA to VenezuelaUloborus canescens C. L. Koch, 1844 – ColombiaUloborus cellarius Yin & Yan, 2012 – ChinaUloborus chinmoyiae Biswas & Raychaudhuri, 2013 – BangladeshUloborus conus Opell, 1982 – New GuineaUloborus crucifaciens Hingston, 1927 – MyanmarUloborus cubicus – MyanmarUloborus diversus Marx, 1898 – United States, MexicoUloborus eberhardi Opell, 1981 – Costa RicaUloborus elongatus Opell, 1982 – ArgentinaUloborus emarginatus Kulczyński, 1908 – Indonesia Uloborus filidentatus Hingston, 1932 – GuyanaUloborus filifaciens Hingston, 1927 – India Uloborus filinodatus Hingston, 1932 – GuyanaUloborus formosanus Yoshida, 2012 – TaiwanUloborus formosus Marx, 1898 – MexicoUloborus furunculus Simon, 1906 – IndiaUloborus gilvus – Italy, GreeceUloborus glomosus – Canada, United States, MexicoUloborus guangxiensis Zhu, Sha & Chen, 1989 – ChinaUloborus humeralis van Hasselt, 1882 – Myanmar, Indonesia

* U. h. marginatus Kulczyński, 1908 – Indonesia Uloborus inaequalis Kulczyński, 1908 – New GuineaUloborus jabalpurensis Bhandari & Gajbe, 2001 – IndiaUloborus jarrei Berland & Millot, 1940 – GuineaUloborus kerevatensis Opell, 1991 – Papua New GuineaUloborus khasiensis Tikader, 1969 – IndiaUloborus krishnae Tikader, 1970 – India Uloborus leucosagma Thorell, 1895 – MyanmarUloborus limbatus Thorell, 1895 – MyanmarUloborus llastay Grismado, 2002 – ArgentinaUloborus lugubris – MyanmarUloborus metae Opell, 1981 – ColombiaUloborus minutus Mello-Leitão, 1915 – BrazilUloborus modestus Thorell, 1891 – India Uloborus montifer Marples, 1955 – SamoaUloborus niger Mello-Leitão, 1917 – BrazilUloborus oculatus Kulczyński, 1908 – SingaporeUloborus parvulus Schmidt, 1976 – Canary IslandsUloborus penicillatoides Xie, Peng, Zhang, Gong & Kim, 1997 – ChinaUloborus pictus Thorell, 1898 – MyanmarUloborus pinnipes Thorell, 1877 – Indonesia Uloborus planipedius Simon, 1897 – South AfricaUloborus plumipes Lucas, 1846 – Europe, Africa, Yemen, Iran, Pakistan. Introduced to Argentina, Philippines, Japan
* U. p. javanus Kulczyński, 1908 – Indonesia Uloborus pteropus – MyanmarUloborus rufus Schmidt & Krause, 1995 – Cape VerdeUloborus scutifaciens Hingston, 1927 – MyanmarUloborus segregatus Gertsch, 1936 – USA to Colombia, GalapagosUloborus sexfasciatus Simon, 1893 – PhilippinesUloborus shendurneyensis Asima, Sudhikumar & Prasad, 2021 – IndiaUloborus spelaeus Bristowe, 1952 – MalaysiaUloborus strandi – EthiopiaUloborus tenuissimus L. Koch, 1872 – SamoaUloborus tetramaculatus Mello-Leitão, 1940 – BrazilUloborus trifasciatus Thorell, 1890 – Indonesia Uloborus trilineatus Keyserling, 1883 – Mexico to ArgentinaUloborus umboniger Kulczyński, 1908 – Sri LankaUloborus undulatus Thorell, 1878 – Indonesia,
* U. u. indicus Kulczyński, 1908 – Malaysia
* U. u. obscurior Kulczyński, 1908 – New Guinea
* U. u. pallidior Kulczyński, 1908 – Indonesia, Uloborus vanillarum Vinson, 1863 – MadagascarUloborus velutinus Butler, 1883 – MadagascarUloborus villosus Keyserling, 1881 – ColombiaUloborus viridimicans Simon, 1893 – PhilippinesUloborus walckenaerius Latreille, 1806 – Madeira, Europe, Turkey, Caucasus, Russia, Iraq, Iran, Kazakhstan, Central Asia, China, Korea, Japan. Introduced to Cape Verde, St. Helena, South Africa