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biodiversity explorer

the web of life in southern Africa

Family: Hersiliidae (Long-spinnered or two-tailed spiders)

Life > Eukaryotes > Opisthokonta > Metazoa (animals) > Bilateria > Ecdysozoa > Panarthropoda > Tritocerebra > Arthropoda > Arachnomorpha > Cheliceriformes > Chelicerata > Euchelicerata > Arachnida > Araneae > Araneomorpha

 

Hersilia sp. Submitted to Biodiversity Explorer for identification by Miles Clarke.

 

Have distinctive elongate lateral spinnerets, which are used in prey capture by swaying them over the victim thus wrapping the victim in silk. Two genera in southern Africa: Hersilia is usually found in trees and Tyrotama is usually found under rocks.

The Hersiliidae is a family of spiders noted for their elongated posterior lateral spinnerets which can be as long as the abdomen in long-spinnered bark spiders and less in rock living species. Hersiliids are small to medium (4.5-12.5mm body length) dorso-ventrally flattened spiders, especially the arboreal genera. They are cryptically coloured in variegated shades of cream, orange, green, brown, grey and black, features they share with the family Selenopidae. Both families are quick and difficult to capture as they disappear into the narrowest of crevices.

As viewed from above, the carapace is oval with the 8 eyes situated in two recurved rows,  on a raised hump or tubercle. The anterior median eyes are largest. The oval abdomen is wider posteriorly with the posterior lateral spinnerets extending out parallel to each other. The inner edge of these spinnerets is lined with silk-producing tubules (spine-like spigots) as opposed to the distally placed spigots of most spiders. The rupicolus genera have shorter spinnerets that are often not seen as they are curled up against the abdomen and the legs are shorter.
Hersilia

Genera indigenous to southern Africa

Hersilia

Hersilia is a diurnal, arboreal genus which can sometimes be found on nearby rocks. They do not spin webs or construct retreats and can often be spotted only by the reflection of the sun on their dragline silk threads. They capture cursorial prey by swaying their long spinnerets over the victim and encircling it wrapping more silk over it. The prey is then bitten and consumed on the spot. The egg sac is wrapped in silk with bits of bark debris attached to aid camouflage.

Tyrotama

Tyrotama is a small to medium (4.8-9.5mm body length) rupicolus genus endemic to South Africa, Namibia and Angola. This genus was until recently known as Tama. They occur in rocky or mountainous areas under stone on rock. They attach themselves under the stone where they construct a circular “kraal” retreat with silk trip lines radiating from it. This “kraal and its egg sac is constructed from silk with embedded sand particles. The prey is caught in the same fashion as the genus Hersilia but is taken to the retreat to be consumed.