Pycnogonum is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of sea spider

Sea spider

Sea spiders, also called Pantopoda or pycnogonids, are marine arthropods of class Pycnogonida. They are cosmopolitan, found especially in the Mediterranean and Caribbean Seas, as well as the Arctic and Antarctic Oceans. There are over 1300 known species, ranging in size from to over in some deep...

s in the family Pycnogonidae

Pycnogonidae

Pycnogonidae is a family of sea spiders.-Characteristics:Most sea spiders in the class Pycnogonida have appendages on the anterior end of the body called chelifores which are used for gathering food and palps which bear sensory organs. Members of the family Pycnogonidae have neither of these,...

.

Characteristics

Members of the genus Pycnogonum have squarish bodies with a tough integument and a few hairs. The cephalon (the anterior end of the body which is fused with the first segment of the trunk) has a long smooth proboscis

Proboscis

A proboscis is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In simpler terms, a proboscis is the straw-like mouth found in several varieties of species.-Etymology:...

 and a low tubercle on which the eyes are set. There are no chelicerae

Chelicerae

The chelicerae are mouthparts of the Chelicerata, an arthropod subphylum that includes arachnids, Merostomata , and Pycnogonida . Chelicerae are pointed appendages which are used to grasp food, and are found in place of the chewing mandibles most other arthropods have...

 or palps

Pedipalp

Pedipalps , are the second pair of appendages of the prosoma in the subphylum Chelicerata. They are traditionally thought to be homologous with mandibles in Crustacea and insects, although more recent studies Pedipalps (commonly shortened to palps or palpi), are the second pair of appendages of the...

 and these sea spiders use their proboscis to suck juices from their prey

Predation

In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...

. On the first segment of the trunk of males there are small ovigerous legs with nine segments. The larva

Larva

A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...

e are carried around by the males on these appendages. The four pairs of ambulatory legs are short but strong, with well-developed terminal claws. The genital openings are on the second segment of the posterior pair of legs.

Species

The World Register of Marine Species lists the following 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...

:

• Pycnogonum africanum Calman, 1938
• Pycnogonum aleuticum Turpaeva, 1994
• Pycnogonum angulirostrum Stock, 1959
• Pycnogonum anovigerum Clark, 1956
• Pycnogonum arbustum Stock, 1966
• Pycnogonum asiaticum Muller, 1992
• Pycnogonum aurilineatum Flynn, 1919
• Pycnogonum benokianum Ohshima, 1935
• Pycnogonum buticulosum Hedgpeth, 1949
• Pycnogonum calculum Bamber, 1995
• Pycnogonum callosum Losina-Losinsky, 1961
• Pycnogonum carinatum Staples, 2002
• Pycnogonum cataphractum Mobius, 1902
• Pycnogonum cessaci Bouvier, 1911
• Pycnogonum clarki Staples, 2002
• Pycnogonum coninsulum Bamber, 2008
• Pycnogonum cranaobyrsa Bamber, 2004
• Pycnogonum crassirostrum Sars, 1888
• Pycnogonum crosnieri Stock, 1991
• Pycnogonum daguilarensis Bamber, 1997
• Pycnogonum diceros Marcus, 1940
• Pycnogonum elephas Stock, 1966
• Pycnogonum eltanin Fry & Hedgpeth, 1969
• Pycnogonum forte Flynn, 1928

• Pycnogonum gaini Bouvier, 1910
• Pycnogonum gibberum Marcus & du Bois Reymond-M., 1963
• Pycnogonum gordonae Pushkin, 1984
• Pycnogonum grumus Arango, 2003
• Pycnogonum guyanae Stock, 1975
• Pycnogonum hancocki Schmitt, 1934
• Pycnogonum indicum Sundara Raj, 1930
• Pycnogonum kussakini Turpaeva, 2000
• Pycnogonum litorale (Strom, 1762)
• Pycnogonum lobipes Stock, 1991
• Pycnogonum madagascariensis Bouvier, 1911
• Pycnogonum magellanicum Hoek, 1898
• Pycnogonum magnirostrum Mobius, 1902
• Pycnogonum microps Loman
• Pycnogonum minutum Losina-Losinsky & Kopaneva, 1973
• Pycnogonum moniliferum Stock, 1991
• Pycnogonum moolenbeeki Stock, 1992
• Pycnogonum mucronatum Loman, 1908
• Pycnogonum musaicum Stock, 1994
• Pycnogonum nodulosum Dohrn, 1881
• Pycnogonum occa Loman, 1908
• Pycnogonum orientale (Dana, 1849)
• Pycnogonum ornans Stock, 1992
• Pycnogonum panamum Hilton, 1942

• Pycnogonum paragaini Munilla, 1990
• Pycnogonum planum Stock, 1954
• Pycnogonum platylophum Loman, 1923
• Pycnogonum plumipes Stock, 1960
• Pycnogonum portus Barnard, 1946
• Pycnogonum pusillum Dohrn, 1881
• Pycnogonum pustulatum Stock, 1994
• Pycnogonum repentinum Turpaeva, 2003
• Pycnogonum repentium Turpaeva, 2003
• Pycnogonum reticulatum Hedgpeth, 1948
• Pycnogonum rickettsi Schmitt, 1934
• Pycnogonum saxulum Child, 1998
• Pycnogonum sivertseni Stock, 1955
• Pycnogonum spatium Takahashi, Dick & Mawatari, 2007
• Pycnogonum stearnsi
  Pycnogonum stearnsi
  Pycnogonum stearnsi or Stearns' sea spider is a marine arthropod in the family Pycnogonidae. It is found on the western seaboard of North America.-Description:...
  
  Ives, 1883
• Pycnogonum stylidium Child, 1995
• Pycnogonum tenue Slater, 1879
• Pycnogonum tesselatum Stock, 1968
• Pycnogonum torresi Clark, 1963
• Pycnogonum tuberculatum Clark, 1963
• Pycnogonum tumulosum Loman, 1908
• Pycnogonum uedai Nakamura & Child, 1983
• Pycnogonum ungellatum Loman, 1911