''Ancylometes'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of Central and

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...

semiaquatic In biology, semiaquatic can refer to various types of animals that spend part of their time in water, or plants that naturally grow partially submerged in water. Examples are given below. Semiaquatic animals Semi aquatic animals include: * Ve ...

wandering spiders first described by

Philipp Bertkau Philipp Bertkau (11 January 1849 – 22 October 1894) was a German zoologist born in Cologne. He studied natural sciences at the University of Bonn, where in 1872 he earned his doctorate. In 1873 he became an assistant at the botanical institute ...

in 1880. Originally placed with the nursery web spiders, it was moved to the

Ctenidae Wandering spiders (''Ctenidae'') are a family of spiders that includes the Brazilian wandering spiders. These spiders have a distinctive longitudinal groove on the top-rear of their oval carapace similar to those of the Amaurobiidae. They are hig ...

in 1967. The genus name is derived in part from

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...

"" ('' ancylo-''), meaning "crooked, bent". These spiders live near ponds, lakes, rivers and other freshwater habitats, and can walk on water like

water striders The Gerridae are a family of insects in the order Hemiptera, commonly known as water striders, water skeeters, water scooters, water bugs, pond skaters, water skippers, or water skimmers. Consistent with the classification of the Gerridae as tr ...

due to fine air-trapping hairs on the tips of their legs. They can also dive under the surface, and can stay underwater for over an hour by using the air trapped in hairs surrounding their book lungs. They will consume anything from insects to small lizards and, occasionally, small fish.

Description

Members of ''Ancylometes'' are among the largest araneomorph spiders, with a typical body length of . They are sometimes referred to as "giant fishing spiders" to distinguish them from ''

Dolomedes ''Dolomedes'' is a genus of large spiders of the family Pisauridae. They are also known as fishing spiders, raft spiders, dock spiders or wharf spiders. Almost all ''Dolomedes'' species are semiaquatic, with the exception of the tree-dwelling ...

'', a genus of smaller spiders also called "fishing spiders". The largest species is ''A. rufus'', with females that grow to a body length of and a leg span of . Males of the species only grow up to in body length, but usually have longer legs than the females. Both sexes are brown with dark spots on the

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 to ...

, and males have two thin lines along their carapace. They have a 2-4-2 eye pattern and a reduced third claw, characteristics of the Ctenidae and Pisauridae, respectively. Members of this genus can be distinguished from all others by ventral spines found on the tarsi of the third and fourth legs. ''Ancylometes'' and the more fully aquatic ''

Argyroneta The diving bell spider or water spider (''Argyroneta aquatica'') is the only species of spider known to live almost entirely under water. It is the only member of the genus ''Argyroneta''. When out of the water, the spider ranges in colour from m ...

'' are the only known genera of spiders that can spin webs in water. Though these webs can catch fish, they mostly prey on fish by diving down or lying in wait until prey passes within striking distance. Once caught, these spiders will bring their prey back to the surface before eating it. During mating, the male wraps the female with silk, and the female enters an immobile state. After about a week, she produces a cocoon and carries it with her fangs. After a month, she builds a nursery web above the ground, about in diameter. Over one hundred baby spiders will hatch inside this egg case, each only about long. The baby spiders take about a year to mature. Males only live for sixteen months at most, while females can live for more than two years. The venom of Acyclomete sp, has effects on muscle contraction and preparation of the phrenic nerve diaphragm muscle, 50 µg causes depolarization of the diaphragm muscle fiber membranes. These studies indicate that the Ancylometes venom activates

voltage-gated sodium channels Sodium channels are integral membrane proteins that form ion channels, conducting sodium ions (Na+) through a cell's membrane. They belong to the superfamily of cation channels and can be classified according to the trigger that opens the chann ...

. All of these effects of Ancylometes sp. venom on this nerve muscle preparation increase in twitch tension.

Species

it contains eleven species: *'' Ancylometes amazonicus''

Simon Simon may refer to: People * Simon (given name), including a list of people and fictional characters with the given name Simon * Simon (surname), including a list of people with the surname Simon * Eugène Simon, French naturalist and the genus ...

, 1898 – Peru, Brazil *'' Ancylometes birabeni'' (Carcavallo & Martínez, 1961) – Argentina *''

Ancylometes bogotensis ''Ancylometes'' is a genus of Central and South American semiaquatic wandering spiders first described by Philipp Bertkau in 1880. Originally placed with the nursery web spiders, it was moved to the Ctenidae in 1967. The genus name is derived ...

'' ( Keyserling, 1877) – Honduras to Bolivia *''

Ancylometes concolor ''Ancylometes'' is a genus of Central and South American semiaquatic wandering spiders first described by Philipp Bertkau in 1880. Originally placed with the nursery web spiders, it was moved to the Ctenidae in 1967. The genus name is derived ...

'' (Perty, 1833) ( type) – Brazil, Bolivia, Paraguay, Argentina *''

Ancylometes hewitsoni ''Ancylometes'' is a genus of Central and South American semiaquatic wandering spiders first described by Philipp Bertkau in 1880. Originally placed with the nursery web spiders, it was moved to the Ctenidae in 1967. The genus name is derived ...

'' ( F. O. Pickard-Cambridge, 1897) – Bolivia, Brazil *''

Ancylometes japura ''Ancylometes'' is a genus of Central and South American semiaquatic wandering spiders first described by Philipp Bertkau in 1880. Originally placed with the nursery web spiders, it was moved to the Ctenidae in 1967. The genus name is derived ...

'' Höfer & Brescovit, 2000 – Brazil *'' Ancylometes jau'' Höfer & Brescovit, 2000 – Brazil *'' Ancylometes pantanal'' Höfer & Brescovit, 2000 – Brazil *'' Ancylometes riparius'' Höfer & Brescovit, 2000 – Brazil *'' Ancylometes rufus'' (

Walckenaer Baron Charles Athanase Walckenaer (25 December 1771 – 28 April 1852) was a French civil servant and scientist. Biography Walckenaer was born in Paris and studied at the universities of Oxford and Glasgow. In 1793 he was appointed head of t ...

, 1837) – Northern South America *'' Ancylometes terrenus'' Höfer & Brescovit, 2000 – Brazil

References

External links

Website especially for the Genus ''Ancylometes'': www.ancylometes.com
{{Taxonbar, from=Q2846015 Ctenidae Spiders of South America Araneomorphae genera

Description

Species

References

Further reading

External links