Pholcidae

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Cellar spiders
Temporal range: Palaeogene–present
Pholcus.phalangioides.6905.jpg
Pholcus phalangioides
CellarSpider.jpg
Close-up of a cellar spider's head, showing two groups of three closely clustered eyes
Scientific classification e
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Araneae
Infraorder: Araneomorphae
Family: Pholcidae
C. L. Koch, 1850
Diversity
94 genera, 1820 species
Distribution.pholcidae.1.png
Estimated range of Pholcidae.

Pholcidae, commonly known as cellar spiders, daddy long-legs spider, granddaddy long-legs spider, carpenter spider, daddy long-legger, vibrating spider and skull spider, is a family of araneomorph spiders first described by Carl Ludwig Koch in 1850.[1] It contains over 1800 species divided in 94 genera.[2]

The common name "daddy long-legs" is used for several species, especially Pholcus phalangioides, but is also the common name for several other arthropod groups, including harvestmen, which are arachnids but not spiders, and crane flies.

Appearance[edit]

Pholcids are thin and fragile arachnids. The body (resembling the shape of a peanut) is approximately 2–10 mm (0.08-0.39 inches) in length, and the legs may be up to 50 mm (1.97 inches) long. Pholcus and Smeringopus have cylindrical abdomens and eyes arranged in two lateral groups of three and two smaller median contiguous eyes. Arrangements of eight and six eyes both occur in this family. Spermophora has a small globose abdomen and its eyes are arranged in two groups of three without median eyes. Pholcids are gray to brown, sometimes clear, with banding or chevron markings.

Habitat[edit]

Pholcids are found in every continent in the world except Antarctica. Pholcids hang inverted in their messy and irregular-shaped webs. These webs are constructed in dark and damp recesses such as in caves, under rocks and loose bark, and in abandoned mammal burrows. In areas of human habitation pholcids construct webs in undisturbed areas in buildings such as attics and cellars (hence the common name "cellar spider").[3]

Behavior[edit]

Cellar spider vibrating rapidly in response to a threat

Trapping[edit]

The web of pholcids has no adhesive properties and instead relies on its irregular structure to trap prey. When pholcid spiders detect prey within their webs the spiders quickly envelop prey with silk-like material before inflicting a fatal bite. The prey may be eaten immediately or stored for later. When finished they will clean the web by unhooking the prey and letting it drop from the web. They are passive against humans.

Threat response[edit]

Some species of Pholcidae exhibit a threat response when disturbed by a touch to the web or entangled large prey. The arachnid responds by vibrating rapidly in a gyrating motion in its web. While other species of spider exhibit this behaviour, such behavior by the Pholcidae species has led to these spiders sometimes being called "vibrating spiders". There are several proposed reasons for this threat response. The movement may make it difficult for a predator to locate the spider or may be a signal to an assumed rival to leave. Vibrating may also increase the chances of capturing insects that have just brushed their web and are still hovering nearby.[4] If the spider continues to be disturbed it will retreat into a corner or drop from its web and escape.

Diet[edit]

Certain species of these spiders invade webs of other spiders to eat the host, the eggs, or the prey. In some cases the spider vibrates the web of other spiders, mimicking the struggle of trapped prey to lure the host closer. Pholcids prey on Tegenaria funnel weaver spiders, and are known to attack and eat redback spiders, huntsman spiders and house spiders.[5][6] Pholcids may be beneficial to humans living in regions with dense hobo spider populations as predation on Tegenaria may keep populations in check.[7]

Gait[edit]

Pholcus phalangioides often uses an alternating tetrapod gait (first right leg, then second left leg, then third right leg, etc.), which is commonly found in many spider species. However, frequent variations from this pattern have been documented during observations of the spiders' movements.

Misconceptions[edit]

There is a legend that daddy long-legs spiders have the most potent venom of any spider, but that their fangs are either too small or too weak to puncture human skin; the same legend is also repeated of the harvestman and crane fly, also known as "daddy long-legs" in some regions. Indeed, pholcid spiders do have a short fang structure (called uncate due to its "hooked" shape). Brown recluse spiders also have uncate fang structure, but are able to deliver medically significant bites.

Possible explanations include: pholcid venom is not toxic to humans; pholcid uncate are smaller than those of brown recluse; or there is a musculature difference between the two arachnids, with recluses, being hunting spiders, possessing stronger muscles for fang penetration.[8] According to Rick Vetter of the University of California at Riverside, the daddy long-legs spider has never harmed a human and there is no evidence that they are dangerous to humans.[9]

The legend may result from the fact that the daddy long-legs spider preys upon deadly venomous spiders, such as the redback, a member of the black widow genus Latrodectus.[10] To the extent that such entomological information was known to the general public, it was perhaps thought that if the daddy long-legs spider could kill a spider capable of delivering fatal bites to humans, then it must be more venomous, and the uncate fangs were regarded as prohibiting it from killing people. In reality, it is able to cast lengths of silk onto its prey, incapacitating them from a safe distance.[11]

Mythbusters experiment[edit]

During 2004, the Discovery Channel television show MythBusters tested the daddy long-legs venom myth in episode 13 - "Buried in concrete". Hosts Jamie Hyneman and Adam Savage first established that the spider's venom was not as toxic as other venoms, after being told about an experiment whereby mice were injected with venom from both a daddy long-legs and a black widow, with the black widow venom producing a much stronger reaction. After measuring the spider's fangs at approximately 0.25 mm, Adam Savage inserted his hand into a container with several daddy-long-legs, and reported that he felt a bite which produced a mild, short-lived burning sensation. The bite did in fact penetrate his skin, but did not cause any notable harm.[12] Additionally, recent research has shown that pholcid venom is relatively weak in its effects on insects.[13]

Genera[edit]

Two Crossopriza lyoni. The bottom one is male. The female is clutching her egg bundle (magnified).
A marbled cellar spider (Holocnemus pluchei) carrying prey.
Smeringopus pallidus female with egg sac.
Male shortbodied cellar spider (Spermophora senoculata) from the United States

As of April 2019, the World Spider Catalog accepts the following genera:[2]

  • Aetana Huber, 2005 — Asia, Fiji
  • Anansus Huber, 2007 — Africa
  • Anopsicus Chamberlin & Ivie, 1938 — Mexico, Ecuador, Caribbean, Central America
  • Apokayana Huber, 2018 — Malaysia, Indonesia
  • Arenita Huber & Carvalho, 2019 — Brazil
  • Arnapa Huber, 2019 — Indonesia, Papua New Guinea
  • Artema Walckenaer, 1837 — Asia, Africa
  • Aucana Huber, 2000 — Chile
  • Aymaria Huber, 2000 — South America
  • Belisana Thorell, 1898 — Asia, Oceania
  • Blancoa Huber, 2000 — Venezuela
  • Buitinga Huber, 2003 — Africa
  • Calapnita Simon, 1892 — Asia
  • Canaima Huber, 2000 — Trinidad, Venezuela
  • Cantikus Huber, 2018 — Asia
  • Carapoia González-Sponga, 1998 — South America
  • Cenemus Saaristo, 2001 — Seychelles
  • Chibchea Huber, 2000 — South America
  • Chisosa Huber, 2000 — Mexico, Aruba, United States
  • Ciboneya Pérez, 2001 — Cuba
  • Coryssocnemis Simon, 1893 — Trinidad, South America, Mexico, Central America
  • Crossopriza Simon, 1893 — Asia, Africa, United States, Venezuela, Germany, Australia
  • Enetea Huber, 2000 — Bolivia
  • Galapa Huber, 2000 — Ecuador
  • Gertschiola Brignoli, 1981 — Argentina
  • Giloloa Huber, 2019 — Indonesia
  • Guaranita Huber, 2000 — Argentina, Brazil
  • Hantu Huber, 2016 — Indonesia
  • Holocneminus Berland, 1942 — Asia, Samoa
  • Holocnemus Simon, 1873 — Spain, Italy, Portugal
  • Hoplopholcus Kulczyński, 1908 — Asia, Greece
  • Ibotyporanga Mello-Leitão, 1944 — Brazil
  • Ixchela Huber, 2000 — Mexico, Central America
  • Kairona Huber & Carvalho, 2019 — Brazil
  • Kambiwa Huber, 2000 — Brazil
  • Kelabita Huber, 2018 — Indonesia, Malaysia
  • Khorata Huber, 2005 — Asia
  • Kintaqa Huber, 2018 — Thailand, Malaysia
  • Leptopholcus Simon, 1893 — Asia, Africa
  • Litoporus Simon, 1893 — South America
  • Magana Huber, 2019 — Oman
  • Mecolaesthus Simon, 1893 — Caribbean, South America
  • Meraha Huber, 2018 — Asia
  • Mesabolivar González-Sponga, 1998 — South America, Trinidad
  • Metagonia Simon, 1893 — North America, South America, Central America, Caribbean
  • Micromerys Bradley, 1877 — Papua New Guinea, Australia
  • Micropholcus Deeleman-Reinhold & Prinsen, 1987 — Morocco, Caribbean, Europe, Asia, Australia
  • Modisimus Simon, 1893 — North America, Central America, Caribbean, Germany, Seychelles, Asia, Australia, South America
  • Muruta Huber, 2018 — Malaysia
  • Nerudia Huber, 2000 — Chile, Argentina
  • Ninetis Simon, 1890 — Africa, Yemen
  • Nipisa Huber, 2018 — Asia
  • Nita Huber & El-Hennawy, 2007 — Egypt, Iran, Uzbekistan
  • Nyikoa Huber, 2007
  • Ossinissa Dimitrov & Ribera, 2005 — Canary Is.
  • Otavaloa Huber, 2000 — South America
  • Paiwana Huber, 2018 — Taiwan
  • Panjange Deeleman-Reinhold & Deeleman, 1983 — Asia, Oceania
  • Papiamenta Huber, 2000 — Curaçao
  • Paramicromerys Millot, 1946 — Madagascar
  • Pehrforsskalia Deeleman-Reinhold & van Harten, 2001 — Africa, Asia
  • Pemona Huber, 2019 — Venezuela
  • Pholcophora Banks, 1896 — United States, Canada, Mexico
  • Pholcus Walckenaer, 1805 — Asia, Europe, Africa, United States, Oceania
  • Physocyclus Simon, 1893 — North America, South America, Czech Republic, Asia, Australia, Central America
  • Pinocchio Huber & Carvalho, 2019 — Brazil
  • Pisaboa Huber, 2000 — Peru, Venezuela, Bolivia
  • Pomboa Huber, 2000 — Colombia
  • Pribumia Huber, 2018 — Asia
  • Priscula Simon, 1893 — South America
  • Psilochorus Simon, 1893 — North America, South America, Asia, New Zealand
  • Quamtana Huber, 2003 — Africa
  • Queliceria González-Sponga, 2003 — Venezuela
  • Saciperere Huber & Carvalho, 2019 — Brazil
  • Savarna Huber, 2005 — Thailand, Malaysia, Indonesia
  • Smeringopina Kraus, 1957 — Africa
  • Smeringopus Simon, 1890 — Africa, Asia, Australia
  • Spermophora Hentz, 1841 — Africa, Asia, Oceania, Germany, Brazil, United States
  • Spermophorides Wunderlich, 1992 — Africa, Europe
  • Stenosfemuraia González-Sponga, 1998 — Venezuela
  • Stygopholcus Absolon & Kratochvíl, 1932 — Croatia, Greece, Montenegro
  • Systenita Simon, 1893 — Venezuela
  • Tainonia Huber, 2000 — Hispaniola
  • Teranga Huber, 2018 — Indonesia, Philippines
  • Tibetia Zhang, Zhu & Song, 2006 — Tibet
  • Tissahamia Huber, 2018 — Asia
  • Tolteca Huber, 2000 — Mexico
  • Trichocyclus Simon, 1908 — Australia
  • Tupigea Huber, 2000 — Brazil
  • Uthina Simon, 1893 — Asia, Seychelles
  • Wanniyala Huber & Benjamin, 2005 — Sri Lanka
  • Waunana Huber, 2000 — Colombia, Ecuador, Panama
  • Wugigarra Huber, 2001 — Australia
  • Zatavua Huber, 2003 — Madagascar

References[edit]

  1. ^ Koch, C. L. (1850). Übersicht des Arachnidensystems. doi:10.5962/bhl.title.39561.
  2. ^ a b "Family: Pholcidae C. L. Koch, 1850". World Spider Catalog. Natural History Museum Bern. Retrieved 2019-04-23.
  3. ^ "Pholcidae information". BioKIDS – Kids' Inquiry of Diverse Species. Animal Diversity Web. Retrieved 15 July 2018.
  4. ^ Marlin, Bruce (25 April 2006). Video of the "vibrating spider" vibrating (QuickTime Movie).
  5. ^ "Daddy Long Legs". Queensland Museum.
  6. ^ Wim van Egmond. "Pholcus phalangioides, the daddy-long-legs spider, in 3D".
  7. ^ "Pholcus phalangioides (Long-bodied Cellar Spider) - Spider Identification & Pictures". spiderid.com. Retrieved 2018-07-15.
  8. ^ "Daddy Long Legs Site on UCR".
  9. ^ "Spider Myths – Daddy Long Legs".
  10. ^ "Family Pholcidae – daddy long-leg spiders". Brisbane Insects and Spiders. 2009. Retrieved 13 November 2009.
  11. ^ "Daddy long-legs".
  12. ^ "Daddy long-leg spiders". Myth Files. Discovery channel.
  13. ^ "The Spider Myths Site". Burke Museum. 12 May 2005.

Bibliography

  • Pinto-da-Rocha, R.; Machado, G.; Giribet, G., eds. (2007). Harvestmen – The biology of opiliones. Harvard University Press. ISBN 0-674-02343-9.

External links[edit]