Meta menardi
Encyclopedia
The European cave spider, , is a long-jawed orb-weaving spider
(Family Tetragnathidae) it is also known as the Orbweaving cave spider, the Cave orbweaver and simply the Cave spider (in context).
extending from Scandinavia
to North Africa
and from Europe
to Korea
, there are also transplanted populations as far apart as Japan
and Madagascar
.
The adult spiders are photophobic
and live in places free from light, frequently in cave
s and tunnel
s, though they can sometimes be seen outside of caves and mines as they will emerge around dusk to hunt, often using a single silk lasso line and swinging down upon their prey to catch, they often have a symbiotic
relationship with cave bats
and are found in areas that are frequented by bats, they are most often observed in railway tunnels and mines since these are more likely to be visited by humans. The young spiders are, in contrast, strongly attracted to light
— probably an evolution
ary adaptation
which ensures the spread of the species to new areas.
with adults reaching roughly 5 cm legspan and 15 mm body length. However, the Cardinal Spider and the raft spider
are larger. It is widespread and locally abundant
, although rarely noticed due to its habits
. They are neither endangered nor protected in the UK.
Egg sacs are tear shaped white pendants (sometimes with a slightly yellow centre) usually hanging from the roof of the habitat by a silk
thread approximately 20 mm long.
is extremely difficult to distinguish from , to the extent that differentiation requires a microscope
and considerable expertise. Meta bourneti has similar range
and habits to and non arachnologists rarely bother with the distinction referring to both species
by the same common name
.
Cave spiders feed on smaller invertebrate
s, most frequently myriapods and slug
s .
The European cave spider is not dangerous
to humans and although (in common with nearly all spiders) they have venom, its effect on large mammals is negligible. They are unlikely to bite if carefully handled but if sufficiently provoked they are capable of inflicting an unpleasant "nip". They are non-aggressive and generally slow moving and are regarded (by arachnophiles
) as "gentle giants".
discovered a colony living in conduit
s and manhole
s. These were incorrectly described as swarms of aggressive spiders, up to 10 cm in size. The error was compounded when they were identified as a new and probably highly venom
ous species by Graham Smith, a misinformed entomologist
. The initial incident was widely reported but when the species was properly identified the matter received little publicity.
Orb-weaver spider
The "typical" orb-weaver spiders are the most common group of builders of spiral wheel-shaped webs often found in gardens, fields and forests...
(Family Tetragnathidae) it is also known as the Orbweaving cave spider, the Cave orbweaver and simply the Cave spider (in context).
Habitat
They have a natural rangeRange (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...
extending from Scandinavia
Scandinavia
Scandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,...
to North Africa
North Africa
North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...
and from Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
to Korea
Korea
Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...
, there are also transplanted populations as far apart as Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
and Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
.
The adult spiders are photophobic
Photophobia
Photophobia is a symptom of abnormal intolerance to visual perception of light. As a medical symptom photophobia is not a morbid fear or phobia, but an experience of discomfort or pain to the eyes due to light exposure or by presence of actual physical photosensitivity of the eyes, though the term...
and live in places free from light, frequently in cave
Cave
A cave or cavern is a natural underground space large enough for a human to enter. The term applies to natural cavities some part of which is in total darkness. The word cave also includes smaller spaces like rock shelters, sea caves, and grottos.Speleology is the science of exploration and study...
s and tunnel
Tunnel
A tunnel is an underground passageway, completely enclosed except for openings for egress, commonly at each end.A tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. Some tunnels are aqueducts to supply water for consumption or for hydroelectric stations or are sewers...
s, though they can sometimes be seen outside of caves and mines as they will emerge around dusk to hunt, often using a single silk lasso line and swinging down upon their prey to catch, they often have a symbiotic
Symbiosis
Symbiosis is close and often long-term interaction between different biological species. In 1877 Bennett used the word symbiosis to describe the mutualistic relationship in lichens...
relationship with cave bats
Cave Myotis
The Cave Myotis is a species of vesper bat in the Vespertilionidae family.It is found in Belize, El Salvador, Guatemala, Honduras, Mexico and in the southwest United States....
and are found in areas that are frequented by bats, they are most often observed in railway tunnels and mines since these are more likely to be visited by humans. The young spiders are, in contrast, strongly attracted to light
Phototaxis
Phototaxis is a kind of taxis, or locomotory movement, that occurs when a whole organism moves in response to the stimulus of light. This is advantageous for phototrophic organisms as they can orient themselves most efficiently to receive light for photosynthesis...
— probably an evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
ary adaptation
Adaptation
An adaptation in biology is a trait with a current functional role in the life history of an organism that is maintained and evolved by means of natural selection. An adaptation refers to both the current state of being adapted and to the dynamic evolutionary process that leads to the adaptation....
which ensures the spread of the species to new areas.
Morphology
They are shiny satin black to reddish brown in colour, often having a different coloured rear body which varies from black,brown or even olive green and are one of the largest spiders found in the United KingdomUnited Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
with adults reaching roughly 5 cm legspan and 15 mm body length. However, the Cardinal Spider and the raft spider
Raft spider
The raft spider, Dolomedes fimbriatus, is a European spider of the family Pisauridae. The raft spider is one of the two largest spiders in the United Kingdom...
are larger. It is widespread and locally abundant
Abundance (ecology)
Abundance is an ecological concept referring to the relative representation of a species in a particular ecosystem. It is usually measured as the large number of individuals found per sample...
, although rarely noticed due to its habits
Habit (biology)
Habit, when used in the context of biology, refers to the instinctive actions of animals and the natural tendencies of plants.In zoology, this term most often refers to specific behavioral characteristics, even when directly related to physiology...
. They are neither endangered nor protected in the UK.
Egg sacs are tear shaped white pendants (sometimes with a slightly yellow centre) usually hanging from the roof of the habitat by a silk
Spider silk
Spider silk is a protein fiber spun by spiders. Spiders use their silk to make webs or other structures, which function as nets to catch other animals, or as nests or cocoons for protection for their offspring...
thread approximately 20 mm long.
is extremely difficult to distinguish from , to the extent that differentiation requires a microscope
Microscope
A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy...
and considerable expertise. Meta bourneti has similar range
Range (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...
and habits to and non arachnologists rarely bother with the distinction referring to both species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
by the same common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
.
Cave spiders feed on smaller invertebrate
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s, most frequently myriapods and slug
Slug
Slug is a common name that is normally applied to any gastropod mollusc that lacks a shell, has a very reduced shell, or has a small internal shell...
s .
The European cave spider is not dangerous
Spider bite
A spider bite is an injury resulting from the bites of spiders or other closely related arachnids.Spiders are active hunters and rely heavily on their bites to paralyze and kill their prey before consuming it. They also bite in self defense...
to humans and although (in common with nearly all spiders) they have venom, its effect on large mammals is negligible. They are unlikely to bite if carefully handled but if sufficiently provoked they are capable of inflicting an unpleasant "nip". They are non-aggressive and generally slow moving and are regarded (by arachnophiles
-phil-
Suffixes with the common part -phil- are used to specify some kind of attraction or affinity to something, in particular the love or obsession with something...
) as "gentle giants".
Media mistakes
A media frenzy was caused when British Telecom engineers working in the grounds of Windsor CastleWindsor Castle
Windsor Castle is a medieval castle and royal residence in Windsor in the English county of Berkshire, notable for its long association with the British royal family and its architecture. The original castle was built after the Norman invasion by William the Conqueror. Since the time of Henry I it...
discovered a colony living in conduit
Water pipe
Water pipes are pipes or tubes, frequently made of polyvinyl chloride , ductile iron, steel, cast iron, polypropylene, polyethylene, or copper, that carry pressurized and treated fresh water to buildings , as well as inside the building.-History:For many centuries, lead was the favoured material...
s and manhole
Manhole
A manhole is an opening used to gain access to sewers or other underground structures, usually for maintenance.Manhole may also refer to:* Manhole , a metal band from Los Angeles* The Manhole, a computer game...
s. These were incorrectly described as swarms of aggressive spiders, up to 10 cm in size. The error was compounded when they were identified as a new and probably highly venom
Venom
Venom is the general term referring to any variety of toxins used by certain types of animals that inject it into their victims by the means of a bite or a sting...
ous species by Graham Smith, a misinformed entomologist
Entomology
Entomology is the scientific study of insects, a branch of arthropodology...
. The initial incident was widely reported but when the species was properly identified the matter received little publicity.
External links
- Pictures of Meta menardi at Nick's Spiders