''Dolomedes'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of large
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 ...
s of the family
Pisauridae
Nursery web spiders (Pisauridae) is a family of Araneomorphae, araneomorph spiders first described by Eugène Simon in 1890. They resemble wolf spiders (Lycosidae) except for several key differences. Wolf spiders have two very prominent eyes in ad ...
. They are also known as fishing spiders, raft spiders, dock spiders or wharf spiders. Almost all ''Dolomedes'' species are
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
Semiaquatic animals include:
* Verte ...
, with the exception of the tree-dwelling ''
D. albineus'' of the
southeastern United States
The Southeastern United States, also referred to as the American Southeast or simply the Southeast, is a geographical region of the United States. It is located broadly on the eastern portion of the southern United States and the southern por ...
. Many species have a striking pale stripe down each side of the body.
They hunt by waiting at the edge of a pool or stream, then when they detect the ripples from prey, they run across the surface to subdue it using their foremost legs, which are tipped with small claws; like other spiders they then inject venom with their hollow jaws to kill and digest the prey. They mainly eat insects, but some larger species are able to catch small fish. They can also climb beneath the water, when they become encased in a silvery film of air. "''Dolomedes''" is derived from the Greek word "δολομήδης" which means wily, deceitful.
There are over a hundred species of ''Dolomedes'' throughout the world; examples include ''
Dolomedes aquaticus
''Dolomedes aquaticus'' is a Dolomedes, fishing spider that lives and hunts along the gravel banks of unforested New Zealand rivers. It prefers open riverbanks where it lives under rocks, usually less than 5 metres from the river. Its colouring a ...
'', a forest-stream species of New Zealand, the
raft spider
The raft spider, scientific name ''Dolomedes fimbriatus'', is a large semi-aquatic spider of the family Pisauridae found throughout north-western and central Europe. It is one of only two species of the genus ''Dolomedes'' found in Europe, the ot ...
(''D. fimbriatus''), which lives in bogs in Europe, and the
great raft spider
The great raft spider or fen raft spider (''Dolomedes plantarius'') is a European species of spider in the family Pisauridae. Like other '' Dolomedes'' spiders, it is semiaquatic, hunting its prey on the surface of water. It occurs mainly in neut ...
(''D. plantarius''), which lives in
fen
A fen is a type of peat-accumulating wetland fed by mineral-rich ground or surface water. It is one of the main types of wetlands along with marshes, swamps, and bogs. Bogs and fens, both peat-forming ecosystems, are also known as mires. T ...
s, also in Europe. Many species are large, some with females up to long with a leg span of .
Aquatic adaptations
''Dolomedes'' spiders are covered all over in short, velvety hairs which are
hydrophobic
In chemistry, hydrophobicity is the physical property of a molecule that is seemingly repelled from a mass of water (known as a hydrophobe). In contrast, hydrophiles are attracted to water.
Hydrophobic molecules tend to be nonpolar and, th ...
. This allows them to use
surface tension
Surface tension is the tendency of liquid surfaces at rest to shrink into the minimum surface area possible. Surface tension is what allows objects with a higher density than water such as razor blades and insects (e.g. water striders) to f ...
to stand or run on the water, like
water strider
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 ...
s. They can also climb beneath the water, and then air becomes trapped in the body hairs and forms a thin film over the whole surface of the body and legs, giving them the appearance of fine polished silver. Like other spiders, ''Dolomedes'' breathe with
book lungs beneath their abdomens, and these open into the air film, allowing the spiders to breathe while submerged. The trapped air makes them very buoyant and even if they do not hold onto a rock or a plant stem they float to the surface where they pop onto the surface film, completely dry.
Identification
If any of this species are seen without context, one may confuse them with the family
Lycosidae
Wolf spiders are members of the family Lycosidae (). They are robust and agile hunters with excellent eyesight. They live mostly in solitude, hunt alone, and do not spin webs. Some are opportunistic hunters, pouncing upon prey as they find it or ...
, otherwise known as Wolf Spiders. Though one could easily identify them, as this genus owns 2 rows of eyes, with 2 larger eyes at the top, which is unique to this genus inside the
Pisauridae
Nursery web spiders (Pisauridae) is a family of Araneomorphae, araneomorph spiders first described by Eugène Simon in 1890. They resemble wolf spiders (Lycosidae) except for several key differences. Wolf spiders have two very prominent eyes in ad ...
family. If this isn't sufficient, one can further differentiate them thanks to their aquatic adaptations.
Hunting behavior
![Fishing Spider and dime](https://upload.wikimedia.org/wikipedia/commons/e/ef/Fishing_Spider_and_dime.jpg)
Rather than hunting on land or by waiting in a web, these spiders hunt on the surface of the water itself, preying on
mayflies
Mayflies (also known as shadflies or fishflies in Canada and the upper Midwestern United States, as Canadian soldiers in the American Great Lakes region, and as up-winged flies in the United Kingdom) are aquatic insects belonging to the orde ...
, other aquatic insects, and even small
fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...
. For fishing spiders, the water surface serves the same function as a web does for other spiders. They extend their legs onto the surface, feeling for vibrations given off by prey.
![Cameroon Clawed frog tadpole being consumed by fishing spider](https://upload.wikimedia.org/wikipedia/commons/5/5c/Cameroon_Clawed_frog_tadpole_being_consumed_by_fishing_spider.jpg)
''Dolomedes'' are nocturnal hunters, feeding when birds, their main predators, are sleeping. The method they use to fish for insects is to hold on to the shore with their back legs while the rest of their body lies on the water, with legs stretched out. ''Dolomedes'' species tend to be robust with thickset legs that allow them to tackle prey larger than themselves. They stretch out their front legs and wait, as if listening. Their front legs feel the vibrations carried on the water, just as other spiders feel the vibrations in a web. They are able to tell what is causing the vibrations that the water is carrying - to distinguish the drawn-out, erratic vibrations of a struggling insect from the one-off vibrations caused by falling leaves or the background noise of the wind or the flow of the water around rocks and other obstacles. As well as identifying the source of the vibrations, the spiders are also able to discern the distance to and direction of the source. To this end they have a range of vibration-detecting organs, including very sensitive hairs (
trichobothria
Trichobothria (singular trichobothrium) are elongate setae ("hairs") present in arachnids, various orders of insects, and myriapods that function in the detection of airborne vibrations and currents, and electrical charge. In 1883, Friedrich Dahl ...
) on their legs and feet. Their eyes play a secondary role - experiments on related species show that touch is the main sense these spiders use to catch their prey. Their eyes are of little use for nocturnal hunting. These vibration detectors also serve to warn the spider of predators such as
trout
Trout are species of freshwater fish belonging to the genera '' Oncorhynchus'', ''Salmo'' and ''Salvelinus'', all of the subfamily Salmoninae of the family Salmonidae. The word ''trout'' is also used as part of the name of some non-salmoni ...
.
As soon as the vibrations reveal that there is a floundering insect within range, some fishing spiders may take direct action - they run at pace across the surface of the water and grab the insect before it extracts itself from the water and flies to safety. Some fishing spiders use
silk
Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the coc ...
draglines to prevent themselves from speeding past the prey.
Fishing spiders' main prey is aquatic insects, but they are opportunistic feeders and will eat anything suitable that happens within range. ''Dolomedes'' in North America have been observed catching and eating small goldfish.
[Greenwood, Michelle, 2008. Aquatic Assassins: The Secret Life of Fishing Spiders. ''New Zealand Geographic'', 91.]
online summary
).
Predators
The main predators of fishing spiders are birds and snakes.
Dragonflies
A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of true dragonfly are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threa ...
have also been observed catching young spiders. Species parasitic on the spiders include a wasp of the
Pompilidae
Wasps in the family Pompilidae are commonly called spider wasps, spider-hunting wasps, or pompilid wasps. The family is cosmopolitan, with some 5,000 species in six subfamilies. Nearly all species are solitary (with the exception of some group-ne ...
family, commonly called the Spider Wasp, that stings the spider to paralyze it before carrying it off and laying an egg in its abdomen. The larvae of the wasp hatch and proceed to eat the spider from the inside out. One escape technique the spiders use is to disappear beneath the surface tension of the water. However, some wasps, such as ''
Anoplius depressipes
''Anoplius depressipes'' is a species of spider wasp in the family Pompilidae. It is a known predator of fishing spiders from the genus ''Dolomedes
''Dolomedes'' is a genus of large spiders of the family Pisauridae. They are also known as f ...
'', are able to be underwater for a few minutes to sting the spider and drag it out of the water.
Breeding
![Dolomedes sling](https://upload.wikimedia.org/wikipedia/commons/4/4d/Dolomedes_sling.jpg)
The males outnumber the females 3:1 suggesting a male-biased sex ratio. Mating in one North American species (''D. tenebrosus'') always results in the obligate death of the male, with no obvious involvement from the female.
["Spontaneous male death and monogyny in the dark fishing spider", Steven K. Schwartz, William E. Wagner Jr and Eileen A. Hebets. Biol. Lett. 23 August 2013 vol. 9 no. 4 20130113. http://rsbl.royalsocietypublishing.org/content/9/4/20130113.long]
Species
, the
World Spider Catalog
The World Spider Catalog (WSC) is an online searchable database concerned with spider taxonomy. It aims to list all accepted families, genera and species, as well as provide access to the related taxonomic literature. The WSC began as a series of ...
accepted the following 101 species:
[
*'']Dolomedes actaeon
''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 ...
'' Pocock, 1903 – Cameroon
*'' Dolomedes albicomus'' L. Koch, 1867 – Australia (Queensland, New South Wales)
*'' Dolomedes albicoxus'' Bertkau, 1880 – Brazil
*''Dolomedes albineus
file:white-banded-fishing-spider.jpg, left, Regional color variation of the white-banded fishing spider, with a white face
''Dolomedes albineus'', the white-banded fishing spider, is a species of nursery web spider in the family Pisauridae. It is ...
'' Hentz, 1845 – USA
*''Dolomedes alexandri
''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 ...
'' Raven & Hebron, 2018 – Australia (Capital Territory, Victoria)
*'' Dolomedes angolensis'' (Roewer, 1955) – Angola
*'' Dolomedes angustivirgatus'' Kishida, 1936 – China, Korea, Japan
*'' Dolomedes angustus'' (Thorell, 1899) – Cameroon
*'' Dolomedes annulatus'' Simon, 1877 – Philippines
*''Dolomedes aquaticus
''Dolomedes aquaticus'' is a Dolomedes, fishing spider that lives and hunts along the gravel banks of unforested New Zealand rivers. It prefers open riverbanks where it lives under rocks, usually less than 5 metres from the river. Its colouring a ...
'' Goyen, 1888 – New Zealand
*'' Dolomedes batesi'' Pocock, 1903 – Cameroon
*''Dolomedes bistylus
''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 ...
'' Roewer, 1955 – Congo
*'' Dolomedes boiei'' (Doleschall, 1859) – Sri Lanka, Indonesia (Java)
*'' Dolomedes briangreenei'' Raven & Hebron, 2018 – Australia (New South Wales, Queensland)
*''Dolomedes bukhkaloi
''Dolomedes'' is a genus of large spiders of the family Nursery web spider, Pisauridae. They are also known as fishing spiders, raft spiders, dock spiders or wharf spiders. Almost all ''Dolomedes'' species are semiaquatic, with the exception o ...
'' Marusik, 1988 – Russia
*'' Dolomedes chevronus'' Yin, 2012 – China
*'' Dolomedes chinesus'' Chamberlin, 1924 – China
*''Dolomedes chroesus
''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 ...
'' Strand, 1911 – Indonesia (Aru Is., New Guinea)
*'' Dolomedes costatus'' Zhang, Zhu & Song, 2004 – China
*'' Dolomedes crosbyi'' Lessert, 1928 – Congo
*'' Dolomedes dondalei'' Vink & Dupérré, 2010 – New Zealand
*'' Dolomedes elegans'' Taczanowski, 1874 – French Guiana
*'' Dolomedes facetus'' L. Koch, 1876 – Australia, New Guinea, Samoa
*'' Dolomedes fageli'' Roewer, 1955 – Congo
*'' Dolomedes femoralis'' Hasselt, 1882 – Indonesia (Sumatra)
*'' Dolomedes fernandensis'' Simon, 1910 – Equatorial Guinea (Bioko)
*''Dolomedes fimbriatus
The raft spider, scientific name ''Dolomedes fimbriatus'', is a large semi-aquatic spider of the family Pisauridae found throughout north-western and central Europe. It is one of only two species of the genus ''Dolomedes'' found in Europe, the ot ...
'' (Clerck, 1757) (type species
In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...
) – Palearctic
*'' Dolomedes flaminius'' L. Koch, 1867 – Australia (Queensland), New Caledonia
*'' Dolomedes fontus'' Tanikawa & Miyashita, 2008 – Japan
*'' Dolomedes furcatus'' Roewer, 1955 – Mozambique
*'' Dolomedes fuscipes'' Roewer, 1955 – Cameroon
*''Dolomedes fuscus
''Dolomedes'' is a genus of large spiders of the family Nursery web spider, Pisauridae. They are also known as fishing spiders, raft spiders, dock spiders or wharf spiders. Almost all ''Dolomedes'' species are semiaquatic, with the exception o ...
'' Franganillo, 1931 – Cuba
*'' Dolomedes gertschi'' Carico, 1973 – USA
*''Dolomedes gracilipes
''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 ...
'' Lessert, 1928 – Congo
*'' Dolomedes guamuhaya'' Alayón, 2003 – Cuba
*'' Dolomedes holti'' Carico, 1973 – Mexico
*''Dolomedes horishanus
''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 ...
'' Kishida, 1936 – Taiwan, Japan
*'' Dolomedes instabilis'' L. Koch, 1876 – Australia, Papua New Guinea
*'' Dolomedes intermedius'' Giebel, 1863 – Colombia
*'' Dolomedes japonicus'' Bösenberg & Strand, 1906 – China, Korea, Japan
*'' Dolomedes kalanoro'' Silva & Griswold, 2013 – Madagascar
*'' Dolomedes karijini'' Raven & Hebron, 2018 – Australia (Western Australia)
*'' Dolomedes karschi'' Strand, 1913 – Sri Lanka
*'' Dolomedes lafoensis'' Berland, 1924 – New Caledonia
*''Dolomedes laticeps
''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 ...
'' Pocock, 1898 – Solomon Is.
*''Dolomedes lesserti
''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 ...
'' Roewer, 1955 – Mozambique
*'' Dolomedes lizturnerae'' Raven & Hebron, 2018 – Australia (Tasmania)
*''Dolomedes machadoi
''Dolomedes'' is a genus of large spiders of the family Nursery web spider, Pisauridae. They are also known as fishing spiders, raft spiders, dock spiders or wharf spiders. Almost all ''Dolomedes'' species are semiaquatic, with the exception o ...
'' Roewer, 1955 – West Africa
*''Dolomedes macrops
''Dolomedes'' is a genus of large spiders of the family Nursery web spider, Pisauridae. They are also known as fishing spiders, raft spiders, dock spiders or wharf spiders. Almost all ''Dolomedes'' species are semiaquatic, with the exception o ...
'' Simon, 1906 – Sudan
*'' Dolomedes mankorlod'' Raven & Hebron, 2018 – Australia (Northern Territory)
*'' Dolomedes mendigoetmopasi'' Barrion, 1995 – Philippines
*''Dolomedes minahassae
''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 ...
'' Merian, 1911 – Indonesia (Sulawesi)
*''Dolomedes minor
''Dolomedes minor'' is a spider in the family Pisauridae that is endemic to New Zealand, where it is known as the nursery web spider.
Identification
''Dolomedes minor'' is pale brown with some being grayish, like the rocks around which they ...
'' L. Koch, 1876 – New Zealand
*'' Dolomedes mizhoanus'' Kishida, 1936 – China, Laos, Malaysia, Taiwan
*''Dolomedes naja
''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 ...
'' Berland, 1938 – Vanuatu
*''Dolomedes neocaledonicus
''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 ...
'' Berland, 1924 – New Caledonia
*'' Dolomedes nigrimaculatus'' Song & Chen, 1991 – China, Korea
*''Dolomedes noukhaiva
''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 ...
'' Walckenaer, 1847 – Marquesas Is.
*'' Dolomedes ohsuditia'' Kishida, 1936 – Japan
*''Dolomedes okefinokensis
''Dolomedes okefinokensis'' is a species of nursery web spider in the family Pisauridae
Nursery web spiders (Pisauridae) is a family of araneomorph spiders first described by Eugène Simon in 1890. They resemble wolf spiders (Lycosidae) except ...
'' Bishop, 1924 – USA
*'' Dolomedes orion'' Tanikawa, 2003 – Japan
*''Dolomedes palmatus
''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 ...
'' Zhang, Zhu & Song, 2005 – China
*'' Dolomedes palpiger'' Pocock, 1903 – Cameroon
*''Dolomedes paroculus
''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 ...
'' Simon, 1901 – Malaysia
*'' Dolomedes pedder'' Raven & Hebron, 2018 – Australia (Tasmania)
*'' Dolomedes pegasus'' Tanikawa, 2012 – Japan
*'' Dolomedes petalinus'' Yin, 2012 – China
*''Dolomedes plantarius
The great raft spider or fen raft spider (''Dolomedes plantarius'') is a European species of spider in the family Pisauridae. Like other ''Dolomedes'' spiders, it is semiaquatic, hunting its prey on the surface of water. It occurs mainly in neutr ...
'' (Clerck, 1757) – Europe, Russia (Europe to South Siberia), Kazakhstan
*'' Dolomedes pullatus'' Nicolet, 1849 – Chile
*'' Dolomedes raptor'' Bösenberg & Strand, 1906 – Russia, China, Korea, Japan
*''Dolomedes raptoroides
''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 ...
'' Zhang, Zhu & Song, 2004 – China
*'' Dolomedes saganus'' Bösenberg & Strand, 1906 – China, Taiwan, Japan
*''Dolomedes schauinslandi
''Dolomedes schauinslandi'' or the Rangatira spider is a large spider of the family Nursery web spider, Pisauridae. It is only found on South East Island (Rangatira), Houruakopara and Mangere Islands in the Chatham Islands, New Zealand. It is on ...
'' Simon, 1899 – New Zealand
*''Dolomedes scriptus
''Dolomedes scriptus'' is a fishing spider found in the United States and Canada, known as the striped fishing spider.Weber, Larry. (2003) Spiders of the North Woods. Duluth, MN:Kollath+Stensaas, 106-107. Female spiders can grow to be over 6&nbs ...
'' Hentz, 1845 – USA, Canada
*''Dolomedes senilis
''Dolomedes'' is a genus of large spiders of the family Nursery web spider, Pisauridae. They are also known as fishing spiders, raft spiders, dock spiders or wharf spiders. Almost all ''Dolomedes'' species are semiaquatic, with the exception o ...
'' Simon, 1880 – Russia, China, Japan
*'' Dolomedes signatus'' Walckenaer, 1837 – Mariana Is.
*'' Dolomedes silvicola'' Tanikawa & Miyashita, 2008 – China, Japan
*'' Dolomedes smithi'' Lessert, 1916 – East Africa
*'' Dolomedes spathularis'' Hasselt, 1882 – Indonesia (Sumatra)
*''Dolomedes stilatus
''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 ...
'' Karsch, 1878 – Australia
*''Dolomedes straeleni
''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 ...
'' Roewer, 1955 – Congo
*'' Dolomedes striatus'' Giebel, 1869 – USA, Canada
*'' Dolomedes sulfureus'' L. Koch, 1878 – Russia, China, Korea, Japan
*'' Dolomedes sumatranus'' Strand, 1906 – Indonesia (Sumatra)
*'' Dolomedes tadzhikistanicus'' Andreeva, 1976 – Tajikistan
*''Dolomedes tenebrosus
''Dolomedes tenebrosus'' or dark fishing spider is a fishing spider found in the USA and Canada.Weber, Larry. (2003). ''Spiders of the North Woods.'' Duluth, MN:Kollath+Stensaas. pp. 104-105.
It is able to bite humans but will run from people. I ...
'' Hentz, 1844 – USA, Canada
*'' Dolomedes titan'' Berland, 1924 – New Caledonia, Vanuatu
*'' Dolomedes toldo'' Alayón, 2003 – Cuba
*'' Dolomedes transfuga'' Pocock, 1900 – Congo
*''Dolomedes triton
''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 ...
'' (Walckenaer, 1837) – North America, Cuba
*''Dolomedes upembensis
''Dolomedes'' is a genus of large spiders of the family Nursery web spider, Pisauridae. They are also known as fishing spiders, raft spiders, dock spiders or wharf spiders. Almost all ''Dolomedes'' species are semiaquatic, with the exception o ...
'' (Roewer, 1955) – Congo
*''Dolomedes vatovae
''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 ...
'' Caporiacco, 1940 – Ethiopia
*''Dolomedes venmani
''Dolomedes venmani'' is a species of araneomorph spider in the family Pisauridae.
Distribution
The species is endemic to Australia. It is found in the south-east of Queensland and the north-east of New South Wales.
Description
The male ho ...
'' Raven & Hebron, 2018 – Australia (New South Wales, Queensland)
*'' Dolomedes vicque'' Raven & Hebron, 2018 – Australia (Victoria, New South Wales, Queensland)
*'' Dolomedes vittatus'' Walckenaer, 1837 – USA
*'' Dolomedes wetarius'' Strand, 1911 – Indonesia
*'' Dolomedes wollastoni'' Hogg, 1915 – New Guinea
*''Dolomedes wollemi
''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 ...
'' Raven & Hebron, 2018 – Australia (New South Wales)
*'' Dolomedes yawatai'' Ono, 2002 – Japan (Ryukyu Is.)
*'' Dolomedes zatsun'' Tanikawa, 2003 – Japan
*'' Dolomedes zhangjiajiensis'' Yin, 2012 – China
Distribution
The approximately 100 species of ''Dolomedes'' have a worldwide distribution. The largest number of species are found in Asia, with particularly high species diversity in South-east Asia, from China and Japan to New Guinea
New Guinea (; Hiri Motu
Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea).
It is a simplified version of ...
. The second largest number of species occur in tropical Africa. South America has only four species.[
]
North America
Nine species of ''Dolomedes'' exist in North America.[ The six-spotted fishing spider ('' D. triton'') lives primarily in small lakes and ponds. This spider consumes mostly ]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 ...
(pond skaters), but like all ''Dolomedes'', it is an opportunistic ambush hunter that will eat anything that it can capture. Other species include the bog-dwelling '' D. striatus'', and four species living by streams: '' D. scriptus'', '' D. vittatus'', '' D. gertschi'' and '' D. holti''. Two North American species, '' D. tenebrosus'' and '' D. okefinokensis'', exhibit female giganticism and/or male dwarfism, with their males being less than half the size of the females. The ninth species is the arboreal
Arboreal locomotion is the Animal locomotion, locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. Th ...
'' D. albineus''.
Europe
Two ''Dolomedes'' species occur in Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...
(excluding Russia).[ The ]Palearctic
The Palearctic or Palaearctic is the largest of the eight biogeographic realms of the Earth. It stretches across all of Eurasia north of the foothills of the Himalayas, and North Africa.
The realm consists of several bioregions: the Euro-Sibe ...
raft spider
The raft spider, scientific name ''Dolomedes fimbriatus'', is a large semi-aquatic spider of the family Pisauridae found throughout north-western and central Europe. It is one of only two species of the genus ''Dolomedes'' found in Europe, the ot ...
(''D. fimbriatus'') is widespread on the surface of bog pools and in boggy grassland
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
. The great raft spider
The great raft spider or fen raft spider (''Dolomedes plantarius'') is a European species of spider in the family Pisauridae. Like other '' Dolomedes'' spiders, it is semiaquatic, hunting its prey on the surface of water. It occurs mainly in neut ...
(''D. plantarius'') lives in fen
A fen is a type of peat-accumulating wetland fed by mineral-rich ground or surface water. It is one of the main types of wetlands along with marshes, swamps, and bogs. Bogs and fens, both peat-forming ecosystems, are also known as mires. T ...
s, and is listed as endangered
An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...
in Great Britain
Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...
and is globally vulnerable.
New Zealand
Four endemic species of ''Dolomedes'' occur in New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
, three on the mainland and one on the Chatham Islands
The Chatham Islands ( ) (Moriori: ''Rēkohu'', 'Misty Sun'; mi, Wharekauri) are an archipelago in the Pacific Ocean about east of New Zealand's South Island. They are administered as part of New Zealand. The archipelago consists of about te ...
. Two are widespread: '' D. aquaticus'' of open riverbanks and lakeshores, and '' D. dondalei'' or New Zealand forest fishing spider (once referred to as ''Dolomedes'' III), which specialises in forested riverbanks. The largest New Zealand species, '' D. schauinslandi'' or the Rangatira spider, occurs on rodent-free islands in the Chathams where running water is rare. The fourth and most common species, '' D. minor'', is found in scrubland, grassland, and wetlands. It mostly hunts on the ground, but is still capable of catching aquatic prey. Known as the nursery web spider, it makes white nursery webs on shrubs.
References
Further reading
*Carico, James Edwin (1973): The Nearctic spiders of the genus ''Dolomedes'' (Araneae: Pisauridae). ''Bulletin of the Museum of Comparative Zoology (Harvard)'' 144 (7): 435-488.
External links
Fishing spider ''Dolomedes tenebrosus''
(free for noncommercial use)
*Jeffrey K. Barnes
Arthropod Museum Notes, University of Arkansas.
*Richard Ford
Digitalwildlife.co.uk. image and short description
{{Taxonbar, from=Q2068864
Araneomorphae genera
Cosmopolitan spiders