Misplaced Pages

Segestria florentina
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Class:	Arachnida
Order:	Araneae
Infraorder:	Araneomorphae
Family:	Segestriidae
Genus:	Segestria
Species:	S. florentina
Binomial name
Segestria florentina (Rossi, 1790)
Synonyms
Aranea subterranea Aranea florentina Aranea perfida Aranea cellaria Segestria perfida Segestria cellaria Segestria gracilis Segestria senoculata

Segestria florentina is the largest European segestriid spider. Some vernacular names are green-fanged tube web spider and cellar spider, although the latter is not exclusive to this species.

Description

Females can 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 iridescent shine, especially on the chelicerae, which reflect with a striking green. The sexes are similar. Adults occur from June to November.

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. However, in some cases the spider will kill and begin to consume its prey in the opening of the tube, but will retreat further if disturbed. They hunt nocturnal insects such as moths and cockroaches. Bees and wasps are always bitten at the head end, so the sting will face away from the spider.

The female lays her eggs inside the tube web. Sometimes she will die after the spiderlings have hatched, and they will eat their mother. The spider can be lured to the entrance by gently touching the triplines with a stick in the evening or at night.

Distribution

Originally a species of the Mediterranean region as far east as Georgia, it can now be found in many towns in southern Britain, where they were probably introduced via seaports at least since 1845. It has been found in several places in Cornwall, South Molton (North Devon) ,Shaftesbury, Torbay, Bradninch (Mid Devon), Jersey, Plymouth, Bristol, North Somerset, Swindon, Gloucester, Ashford, Folkestone, Deal, Dover, Hayes, Southampton, Salisbury, Whitstable, Canterbury, South East London, Vinters Park, Maidstone, Portsmouth, Exeter, Sittingbourne, Isle of Sheppey, Essex, Faversham, Tonbridge, Hitchin, Sheffield, Bridgwater and Newport, where it prefers south-facing walls. Specimens have been found in Exeter Cathedral as far back as 1890. In 2023, it was reported that a population was established in Limerick in western Ireland. It has also been found in Argentina, Australia and several Atlantic islands, where it was probably also introduced.

Many specimens inhabit Westminster Abbey in an isolated population group that has been proposed as a new subspecies due to their fangs being brighter green and their size been significantly smaller to other European populations.

Egg-laying females are known to prefer the habitation of brick structured buildings. During winter months, females will lay eggs within the bricks of south facing structures. If a female is found between the months of September and October, it is highly likely that she has laid eggs in preparation for the next spring. Infestation of buildings is possible if not found and treated early.

Bite

Its bite is reported to be extremely painful. It has been compared to a "deep injection", and the pain can last for several hours.

Two neurotoxins and one insecticide were found in the venom. The venom reduces the rate and amount of sodium inactivation. Bites are reported to feel like a bee sting, which would make it a 2 on the Schmidt sting pain index, but do not have any lasting effects.

References

1. "Green-fanged Tube Web Spider". srs.britishspiders.org.uk. Retrieved 19 August 2020.
2. ^ Bellmann, H. (1997). Kosmos-Atlas Spinnentiere Europas. Kosmos.
3. ^ "Tube web spider, Segestria florentina". Natural History Museum. Archived from the original on 2013-06-21. Retrieved 2009-09-26.
4. ^ "Science & Nature - Wildfacts - Tube web spider". BBC. Archived from the original on 2009-06-08. Retrieved 2009-09-26.
5. "Nick's Spiders - Segestria florentina". Nicksspiders.com. Retrieved 2009-09-26.
6. "Rare Segestria Florentina spider colony found in Gloucester street". Thisisgloucestershire.co.uk. Retrieved 2009-09-26.
7. "Devon girl finds green-fanged spider". BBC News. 2010-10-05. Retrieved 2024-07-13.
8. "Andy Seaman's spider lodge". kentonline.co.uk. Retrieved 2012-11-01.
9. "Bridgwater homes infested with Mediterranean spiders". Bridgwater Mercury. 2014-09-30. Retrieved 2014-10-28.
10. "Fanged cannibalistic tube spiders with bite like bee sting found in street in Wales". Wales Online. WalesOnline. 8 October 2014. Retrieved 8 October 2014.
11. "Segestria florentina in Cornwall". Stevehopkin.co.uk. Retrieved 2009-09-26.
12. "Proceedings".
13. Wild Devon - The Magazine of the Devon Wildlife Trust, pp 4-7, Winter 2009
14. Nolan, Myles & Doe, Jane (2023). "The green-jawed tube spider Segestria florentina (Rossi) (Araneae: Segestriidae) is established in Ireland" (PDF). Bulletin of the Irish Biogeographical Society (46): 124–133. Retrieved 2024-11-04.
15. Bonte, D., Criel, P., van Thournout, I. & Maelfait, J-P. 2003. Regional and local variation of spider assemblages (Araneae) from coastal grey dunes along the North Sea. J. Biogeogr. 30: 901-911.
16. Sagdiev, N.Zh.; Valieva, L.A.; Korneev, A.S.; Sadykov, A.A.; Salikhov, Sh.I. (August 1987). "Toxic components of the venom of the cellar spider Segestria florentina". Bioorganicheskaia Khimiia. 13 (8): 1013–1018. PMID 3675645.
17. "BBC - Science & Nature - Wildfacts - Tube web spider". Archived from the original on 2009-06-08. Retrieved 2009-09-26.

• Segestriidae
• Spiders of Europe
• Spiders of Asia
• Spiders of Africa
• Spiders described in 1790