Pycnogonum is a genus of sea spiders in the family Pycnogonidae. It is the type genus of the family.
Etymology
The generic name literally means âÂÂdense kneesâÂÂ. Pycnogonum combines the prefix ' (from âÂÂdenseâ in Greek) with the Greek word for "knee": ().
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 and a low tubercle on which the eyes are set. There are no chelicerae or palps and these sea spiders use their proboscis to suck juices from their prey. On the first segment of the trunk of males there are small ovigerous legs with nine segments. The larvae 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:
- Pycnogonum africanum<small> Calman, 1938</small>
- Pycnogonum aleuticum<small> Turpaeva, 1994</small>
- Pycnogonum angulirostrum<small> Stock, 1959</small>
- Pycnogonum anovigerum<small> Clark, 1956</small>
- Pycnogonum arbustum<small> Stock, 1966</small>
- Pycnogonum asiaticum<small> Muller, 1992</small>
- Pycnogonum aurilineatum<small> Flynn, 1919</small>
- Pycnogonum benokianum<small> Ohshima, 1935</small>
- Pycnogonum buticulosum<small> Hedgpeth, 1949</small>
- Pycnogonum calculum<small> Bamber, 1995</small>
- Pycnogonum callosum<small> Losina-Losinsky, 1961</small>
- Pycnogonum carinatum<small> Staples, 2002</small>
- Pycnogonum cataphractum<small> Mobius, 1902</small>
- Pycnogonum cessaci<small> Bouvier, 1911</small>
- Pycnogonum clarki<small> Staples, 2002</small>
- Pycnogonum coninsulum<small> Bamber, 2008</small>
- Pycnogonum cranaobyrsa<small> Bamber, 2004</small>
- Pycnogonum crassirostrum<small> Sars, 1888</small>
- Pycnogonum crosnieri<small> Stock, 1991</small>
- Pycnogonum daguilarensis<small> Bamber, 1997</small>
- Pycnogonum diceros<small> Marcus, 1940</small>
- Pycnogonum elephas<small> Stock, 1966</small>
- Pycnogonum eltanin<small> Fry & Hedgpeth, 1969</small>
- Pycnogonum forte<small> Flynn, 1928</small>
- Pycnogonum gaini<small> Bouvier, 1910</small>
- Pycnogonum gibberum<small> Marcus & du Bois Reymond-M., 1963</small>
- Pycnogonum gordonae<small> Pushkin, 1984</small>
- Pycnogonum grumus<small> Arango, 2003</small>
- Pycnogonum guyanae<small> Stock, 1975</small>
- Pycnogonum hancocki<small> Schmitt, 1934</small>
- Pycnogonum indicum<small> Sundara Raj, 1930</small>
- Pycnogonum kussakini<small> Turpaeva, 2000</small>
- Pycnogonum litorale<small> (Strom, 1762)</small>
- Pycnogonum lobipes<small> Stock, 1991</small>
- Pycnogonum madagascariensis<small> Bouvier, 1911</small>
- Pycnogonum magellanicum<small> Hoek, 1898</small>
- Pycnogonum magnirostrum<small> Mobius, 1902</small>
- Pycnogonum microps<small> Loman</small>
- Pycnogonum minutum<small> Losina-Losinsky & Kopaneva, 1973</small>
- Pycnogonum moniliferum<small> Stock, 1991</small>
- Pycnogonum moolenbeeki<small> Stock, 1992</small>
- Pycnogonum mucronatum<small> Loman, 1908</small>
- Pycnogonum musaicum<small> Stock, 1994</small>
- Pycnogonum nodulosum<small> Dohrn, 1881</small>
- Pycnogonum occa<small> Loman, 1908</small>
- Pycnogonum orientale<small> (Dana, 1849)</small>
- Pycnogonum ornans<small> Stock, 1992</small>
- Pycnogonum panamum<small> Hilton, 1942</small>
- Pycnogonum paragaini<small> Munilla, 1990</small>
- Pycnogonum planum<small> Stock, 1954</small>
- Pycnogonum platylophum<small> Loman, 1923</small>
- Pycnogonum plumipes<small> Stock, 1960</small>
- Pycnogonum portus<small> Barnard, 1946</small>
- Pycnogonum pusillum<small> Dohrn, 1881</small>
- Pycnogonum pustulatum<small> Stock, 1994</small>
- Pycnogonum repentinum<small> Turpaeva, 2003</small>
- Pycnogonum repentium<small> Turpaeva, 2003</small>
- Pycnogonum reticulatum<small> Hedgpeth, 1948</small>
- Pycnogonum rickettsi<small> Schmitt, 1934</small>
- Pycnogonum saxulum<small> Child, 1998</small>
- Pycnogonum sivertseni<small> Stock, 1955</small>
- Pycnogonum spatium<small> Takahashi, Dick & Mawatari, 2007</small>
- Pycnogonum stearnsi<small> Ives, 1883</small>
- Pycnogonum stylidium<small> Child, 1995</small>
- Pycnogonum tenue<small> Slater, 1879</small>
- Pycnogonum tesselatum<small> Stock, 1968</small>
- Pycnogonum torresi<small> Clark, 1963</small>
- Pycnogonum tuberculatum<small> Clark, 1963</small>
- Pycnogonum tumulosum<small> Loman, 1908</small>
- Pycnogonum uedai<small> Nakamura & Child, 1983</small>
- Pycnogonum ungellatum<small> Loman, 1911</small>
References