''Segestria senoculata'', sometimes known as the snake-back spider, is a species of

spider Spiders ( order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species ...

belonging to the family

Segestriidae Tube-dwelling spiders (Segestriidae) are a family of araneomorph spiders first described by Eugène Simon in 1893. It consists of five genera, two large and widespread, '' Segestria'' and ''Ariadna'', and three smaller genera, '' Citharoceps'', ...

. It has a

Palearctic The Palearctic or Palaearctic is the largest of the eight biogeographic realms of the Earth. It stretches across all of Eurasia north of the foothills of the Himalayas, and North Africa. The realm consists of several bioregions: the Euro-Sibe ...

distribution. The common names of this species (which has a body length of around 9 mm) refer to a row of black spots along the back of the grey

abdomen The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. ...

which are thought to resemble the pattern found on some

snake Snakes are elongated, Limbless vertebrate, limbless, carnivore, carnivorous reptiles of the suborder Serpentes . Like all other Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), scales. Ma ...

s. However, on some specimens these markings fuse to form a solid band. The

carapace A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...

is shiny dark brown and elongated and the legs are pale brown with darker ringing. As with other members of this family, this spider makes a tubular web in a crevice and darts out to catch prey which crosses trip lines which fan out from the tube's entrance. ''Segestria senoculata'' is the only recorded prey for the Pepsid

spider wasp Wasps in the family Pompilidae are commonly called spider wasps, spider-hunting wasps, or pompilid wasps. The family is cosmopolitan, with some 5,000 species in six subfamilies. Nearly all species are solitary (with the exception of some group-ne ...

Dipogon subintermedius ''Dipogon subintermedius'' is a spider wasp from the family Pompilidae. Identification Like '' D. bifasciatus'', this is an all-black species with bifasciated wings, but the female has shorter antennae than ''D. bifasciatus''. Distribution and h ...

'' in

Great Britain Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...

.Edwards R. & Broad G. (eds), 2005, Provisional Atlas for the aculeate Hymenoptera of Britain and Ireland, NERC

References

* * (2008)
The world spider catalog
version 8.5. ''American Museum of Natural History''.

External links

Known world distribution

www.habitas.org.uk/invertebrateireland
* The checklist of Lithuanian spiders (Arachnida: Araneae). Marija Biteniekytė and Vygandas Rėlys, Biologija, 2011, Vol. 57, No. 4, pages 148–158, Segestriidae Spiders described in 1758 Taxa named by Carl Linnaeus Spiders of Europe Palearctic spiders {{Araneomorphae-stub