The Varunidae are a
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
of
thoracotremata
Thoracotremata is a clade of crabs, comprising those crabs in which the genital openings in both sexes are on the sternum, rather than on the legs. It comprises 17 families in four superfamilies .
Evolution
Thoracotremata is the sister gro ...
n
crab
Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( el, βραχύς , translit=brachys = short, / = tail), usually hidden entirely under the thorax. They live in all the ...
s. The delimitation of this family, part of the
taxonomical
In biology, taxonomy () is the scientific study of naming, defining ( circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxa (singular: taxon) and these groups are given ...
ly confusing
Grapsoidea
The Grapsoidea are a superfamily of crabs; they are well known and contain many taxa which are terrestrial (land-living), semiterrestrial (taking to the sea only for reproduction), or limnic (living in fresh water). Another well-known member w ...
, is undergoing revision. For a long time, they were placed at the rank of
subfamily
In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...
in the
Grapsidae
The Grapsidae are a family of crabs known variously as marsh crabs, shore crabs, or talon crabs. The family has not been confirmed to form a monophyletic group and some taxa may belong in other families. They are found along the shore among rocks ...
, but they appear to be closest to ''
Macropthalmus'' and the
Mictyridae
''Mictyris'' is a genus of brightly coloured crabs, placed in its own taxonomical family, the Mictyridae. It inhabits the central Indo-West Pacific region. These crabs congregate on mud flats or beaches in groups of a few thousand, and filter sa ...
, which are usually placed in the
Ocypodoidea
The Ocypodoidea, or ocypoid crabs, are a superfamily of crabs, named after the genus '' Ocypode''. It contains over 300 extant species in these eight families:
* Camptandriidae Stimpson, 1858
* Dotillidae Stimpson, 1858
* Heloeciidae H. Miln ...
. It may thus be better to merge the latter superfamily with the Grapsoidea, retaining the latter name as it is older.
That notwithstanding, the revision of the Grapsoidea (in the narrow but apparently still
paraphyletic
In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...
sense) is also not fully completed, as many
taxa
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...
remain to be restudied. Already, several former Grapsidae
genera
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 nomenclat ...
have been moved to the Varunidae, and others are tentatively placed here pending detailed study. Among the most noteworthy of these is the
Chinese mitten crab
The Chinese mitten crab ('; , "big sluice crab"), also known as the Shanghai hairy crab (, p ''Shànghǎi máoxiè''), is a medium-sized burrowing crab that is named for its furry claws, which resemble mittens. It is native to river ...
, ''Eriocheir sinensis''.
The genus ''
Xenograpsus'', formerly included in the Varunidae, is now placed in its own family, the
Xenograpsidae.
The following genera are included:
;Asthenognathinae
Stimpson, 1858
*''
Asthenognathus''
Stimpson, 1858
*''
Globihexapus'' †
Schweitzer & Feldmann, 2001
;Cyclograpsinae
H. Milne-Edwards, 1853
*''
Austrohelice''
K. Sakai, Türkay & Yang, 2006
*''
Chasmagnathus
''Chasmagnathus convexus'' is a common mud-flat crab of the family (biology), family Varunidae, which is endemism, endemic to East Asia. In Japan, this crab is commonly called ''hamagani''. This crab has two forms that differ in color; one is ol ...
''
De Haan, 1833
*''
Cyclograpsus
''Cyclograpsus'' is a genus of crabs, containing the following species:
*'' Cyclograpsus audouinii'' H. Milne-Edwards, 1837
*'' Cyclograpsus barbatus'' (MacLeay, 1838)
*'' Cyclograpsus beccarii'' Nobili, 1899
*'' Cyclograpsus cinereus'' Dana, 18 ...
''
H. Milne-Edwards, 1837
*''
Helicana''
K. Sakai & Yatsuzuka, 1980
*''
Helice''
De Haan, 1833
*''
Helograpsus''
Campbell & Griffin, 1966
*''
Metaplax''
H. Milne-Edwards, 1852
*''
Miosesarma'' †
Karasawa, 1989
*''
Neohelice''
K. Sakai, Türkay & Yang, 2006
*''
Paragrapsus''
H. Milne-Edwards, 1853
*''
Parahelice''
K. Sakai, Türkay & Yang, 2006
*''
Pseudohelice''
K. Sakai, Türkay & Yang, 2006
;Gaeticinae
Davie & N. K. Ng, 2007
*''
Gaetice''
Gistel, 1848
*''
Gopkittisak''
Naruse & P. F. Clark, 2009
*''
Sestrostoma''
Davie & N. K. Ng, 2007
;Thalassograpsinae
Davie & N. K. Ng, 2007
*''
Thalassograpsus''
Tweedie, 1950
;Varuninae
H. Milne-Edwards, 1853
*''
Acmaeopleura''
Stimpson, 1858
*''
Brachynotus''
De Haan, 1833
*''
Cyrtograpsus''
Dana, 1851
*''
Eriocheir''
De Haan, 1835
*''
Grapsodius''
Holmes, 1900
*''
Hemigrapsus
''Hemigrapsus'' is a genus of varunid crabs comprising thirteen species native almost exclusively in the Pacific Ocean, but two have been introduced to the North Atlantic region.
Biogeography
The natural range of the genus is restricted to th ...
''
Dana, 1851
*''
Neoeriocheir''
T. Sakai, 1983
*''
Noarograpsus''
N. K. Ng, Manuel & Ng, 2006
*''
Orcovita''
Ng & Tomascik, 1994
*''
Otognathon''
Ng & Stevcic, 1993
*''
Parapyxidognathus''
Ward, 1941
*''
Platyeriocheir''
N. K. Ng, J. Guo & Ng, 1999
*''
Pseudogaetice''
Davie & N. K. Ng, 2007
*''
Pseudograpsus''
H. Milne-Edwards, 1837
*''
Ptychognathus''
Stimpson, 1858b
*''
Pyxidognathus''
A. Milne-Edwards, 1879
*''
Scutumara''
Ng & Nakasone, 1993
*''
Tetragrapsus''
Rathbun, 1918
*''
Utica''
White, 1847
*''
Varuna
Varuna (; sa, वरुण, , Malay: ''Baruna'') is a Vedic deity associated initially with the sky, later also with the seas as well as Ṛta (justice) and Satya (truth). He is found in the oldest layer of Vedic literature of Hinduism, such ...
''
Milne-Edwards, 1830
References
External links
{{Taxonbar, from=Q2130342
Grapsoidea
Taxa named by Henri Milne-Edwards
Decapod families