''Segestria florentina'' is the biggest European segestriid

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 ...

. 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 The opisthosoma is the posterior part of the body in some arthropods, behind the prosoma ( cephalothorax). It is a distinctive feature of the subphylum Chelicerata (arachnids, horseshoe crabs and others). Although it is similar in most respects to ...

with a marking similar to '' Segestria senoculata'', adults are of a uniform black, sometimes with a green iridescent shine, especially on the

chelicerae The chelicerae () are the mouthparts of the subphylum Chelicerata, an arthropod group that includes arachnids, horseshoe crabs, and sea spiders. Commonly referred to as " jaws", chelicerae may be shaped as either articulated fangs, or similarl ...

,Bellmann, H. (1997). Kosmos-Atlas Spinnentiere Europas. ''Kosmos''. 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

moth Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of w ...

s and

cockroach Cockroaches (or roaches) are a Paraphyly, paraphyletic group of insects belonging to Blattodea, containing all members of the group except termites. About 30 cockroach species out of 4,600 are associated with human habitats. Some species are we ...

es. Bees and

wasp A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. ...

s 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 Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...

, 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 Cornwall (; kw, Kernow ) is a historic county and ceremonial county in South West England. It is recognised as one of the Celtic nations, and is the homeland of the Cornish people. Cornwall is bordered to the north and west by the Atlantic ...

, South Molton North Devon, Newcastle, Torbay, Bradninch (Mid Devon),

Jersey Jersey ( , ; nrf, Jèrri, label= Jèrriais ), officially the Bailiwick of Jersey (french: Bailliage de Jersey, links=no; Jèrriais: ), is an island country and self-governing Crown Dependency near the coast of north-west France. It is the l ...

, Plymouth,

Bristol Bristol () is a city, ceremonial county and unitary authority in England. Situated on the River Avon, it is bordered by the ceremonial counties of Gloucestershire to the north and Somerset to the south. Bristol is the most populous city in ...

, North Somerset, Swindon,

Gloucester Gloucester ( ) is a cathedral city and the county town of Gloucestershire in the South West of England. Gloucester lies on the River Severn, between the Cotswolds to the east and the Forest of Dean to the west, east of Monmouth and east ...

, Ashford, Folkestone,

Deal A deal, or deals may refer to: Places United States * Deal, New Jersey, a borough * Deal, Pennsylvania, an unincorporated community * Deal Lake, New Jersey Elsewhere * Deal Island (Tasmania), Australia * Deal, Kent, a town in England * Deal, ...

, Dover, Hayes,

Southampton Southampton () is a port city in the ceremonial county of Hampshire in southern England. It is located approximately south-west of London and west of Portsmouth. The city forms part of the South Hampshire built-up area, which also covers Po ...

Salisbury Salisbury ( ) is a cathedral city in Wiltshire, England with a population of 41,820, at the confluence of the rivers Avon, Nadder and Bourne. The city is approximately from Southampton and from Bath. Salisbury is in the southeast of ...

Whitstable Whitstable () is a town on the north coast of Kent adjoining the convergence of the Swale Estuary and the Greater Thames Estuary in southeastern England, north of Canterbury and west of Herne Bay. The 2011 Census reported a population of ...

Canterbury Canterbury (, ) is a cathedral city and UNESCO World Heritage Site, situated in the heart of the City of Canterbury local government district of Kent, England. It lies on the River Stour. The Archbishop of Canterbury is the primate of ...

, South East London,

Vinters Park, Maidstone Vinters Valley Park is a Local Nature Reserve in Maidstone in Kent. It is owned by Kent County Council and Maidstone Borough Council and managed by the Vinters Valley Trust. This park has diverse habitats with grassland, woods, marshes, scrub ...

Portsmouth Portsmouth ( ) is a port and city in the ceremonial county of Hampshire in southern England. The city of Portsmouth has been a unitary authority since 1 April 1997 and is administered by Portsmouth City Council. Portsmouth is the most dens ...

, Exeter,

Sittingbourne Sittingbourne is an industrial town in Kent, south-east England, from Canterbury and from London, beside the Roman Watling Street, an ancient British trackway used by the Romans and the Anglo-Saxons and next to the Swale, a strip of sea separa ...

Isle of Sheppey The Isle of Sheppey is an island off the northern coast of Kent, England, neighbouring the Thames Estuary, centred from central London. It has an area of . The island forms part of the local government district of Swale. ''Sheppey'' is derive ...

Essex Essex () is a county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the River Thames to the south, and Grea ...

Faversham Faversham is a market town in Kent, England, from London and from Canterbury, next to the Swale, a strip of sea separating mainland Kent from the Isle of Sheppey in the Thames Estuary. It is close to the A2, which follows an ancient Briti ...

Tonbridge Tonbridge ( ) is a market town in Kent, England, on the River Medway, north of Royal Tunbridge Wells, south west of Maidstone and south east of London. In the administrative borough of Tonbridge and Malling, it had an estimated populat ...

Sheffield Sheffield is a city in South Yorkshire, England, whose name derives from the River Sheaf which runs through it. The city serves as the administrative centre of the City of Sheffield. It is historically part of the West Riding of Yorkshire a ...

, Bridgwater and Newport, where it prefers south-facing walls. Specimens have been found in Exeter Cathedral as far back as 1890. It has also been found in

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

, Australia and several

Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe an ...

islands, where it was probably also introduced. 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 reportedly quite 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 Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable ...

inactivation. Bites are reported to feel like a bee sting, which would make it a 2 on the

Schmidt sting pain index The Schmidt sting pain index is a pain scale rating the relative pain caused by different hymenopteran stings. It is mainly the work of Justin O. Schmidt (born 1947), an entomologist at the Carl Hayden Bee Research Center in Arizona, United Sta ...

, but do not have any lasting effects.

References

{{Taxonbar, from=Q141264 Segestriidae Spiders of Europe Spiders of Asia Spiders of Africa Spiders described in 1790