Segestria florentina

Taxobox
name = "Segestria florentina"

---

image_caption =
image_width = 250px
regnum = Animalia
phylum = Arthropoda
classis = Arachnida
ordo = Araneae
subordo = Araneomorphae
familia = Segestriidae
subfamilia =
genus = "Segestria"
species = "S. florentina"
binomial = "Segestria florentina"
binomial_authority = (Rossi, 1790)
range_

---

range_map_width = 250px
synonyms ="Aranea subterranea"
"Aranea florentina"
"Aranea perfida"
"Aranea cellaria"
"Segestria perfida"
"Segestria cellaria"
"Segestria gracilis"
"Segestria senoculata"

"Segestria florentina" is the biggest segestriid spider of Europe. Some common names are tube web spider or cellar spider, although both are not specific to this species.

Description

Females reach a body length of 22 mm, males up to 15 mm. This species is much darker than others of the same genus. While subadult spiders have a greyish opisthosoma with a marking similar to "Segestria senoculata", adults are of a uniform black, sometimes with a green metallic shine, especially on the fangs.Bellmann, H. (1997). Kosmos-Atlas Spinnentiere Europas. "Kosmos".] reflect with a striking green. The sexes are similar. Adults occur from June to November. [http://www.nhm.ac.uk/nature-online/life/insects-spiders/spiderbites/tube-web-spider-segestria-florentina.html]

Habits

They spin a tubular web, often in cracks of buildings. Six or more silken lines radiate from it, and the spider waits in the entrance, touching the lines with the frontal six legs. Prey triggering these lines get caught, and the spider immediately retreats again to eat it in its retreat. They hunt nocturnal insects such as moths and cockroaches, but disdain woodlice. Bees and wasps are always bitten at the head end, so the sting will face away from the spider. [http://www.bbc.co.uk/nature/wildfacts/factfiles/359.shtml]

The eggs are deposited inside the tube web. Sometimes the female will die after the spiderlings have hatched, and they will eat their mother. [http://www.nicksspiders.com/nicksspiders/segestriaflorentina.htm] The spider can be lured to the entrance by gently touching the triplines with a stick in the evening or at night. [http://www.bbc.co.uk/nature/wildfacts/factfiles/359.shtml]

Distribution

Originally a species of the Mediterranean region as far east as Georgia, it can even be found in several large British towns (for example Bristol), where they were probably introduced via seaports at least since 1845. [http://nbn.nhm.ac.uk/nhm/bin/nbntaxa.dll/taxon_details?taxon_key=NBNSYS0000008637] It has been found in several places in Cornwall and Bristol here it prefers walls facing south. [http://www.stevehopkin.co.uk/cornishspiders/007SEGflo/] It has also been found in Argentina, Australia and several Atlantic islands, where it was probably also introduced.

Bite

Its bite is reportedly quite painful.Bellmann, H. (1997). Kosmos-Atlas Spinnentiere Europas. "Kosmos".] It feels like a deep injection, and the pain can last for several hours. [http://www.nhm.ac.uk/nature-online/life/insects-spiders/spiderbites/tube-web-spider-segestria-florentina.html]

Two neurotoxins and one insecticide were found in the venom. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3675645&dopt=Abstract] The venom reduces the rate and amount of sodium inactivation. This effect is probably responsible for the prolongation of the action potential. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=2413900&query_hl=2]

References