Hexapodidae

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Cladus: Protostomia
Cladus: Ecdysozoa
Cladus: Panarthropoda
Phylum: Arthropoda
Subphylum: Crustacea
Superclassis: Multicrustacea
Classis: Malacostraca
Subclassis: Eumalacostraca
Superordo: Eucarida
Ordo: Decapoda
Subordo: Pleocyemata
Infraordo: Brachyura
Sectio: Eubrachyura
Subsectio: Heterotremata
Superfamilia: Xanthoidea

Familia: Hexapodidae
Genera: Hexapinus - Hexaplax - Hexapus - Lambdophallus - Latohexapus - Mariaplax – Paeduma - Parahexapus - Pseudohexapus - Rayapinus - Spiroplax - Stevea - Thaumastoplax - Theoxapus - Tritoplax

Check: †Bellhexapus – †Eohexapus – †Eurohexapus – †Goniocypoda – †Holthuisea
References

Ng, P.K.L. & Rahayu, D.L. 2015. Notes on Hexapodidae (Crustacea, Brachyura) from Indonesia and Malaysia, with description of a new species of Mariaplax Rahayu & Ng, 2014, from Lombok, Indonesia. Zootaxa 3981(1): 125–137. DOI: 10.11646/zootaxa.3981.1.7. Preview (PDF). Reference page.
Rahayu, D.L. & Widyastuti, E. 2018. Additions to the Indonesian crab fauna of the genus Mariaplax Rahayu & Ng, 2014, and notes on Hexapus timika Rahayu & Ng, 2014 (Crustacea, Decapoda, Brachyura, Hexapodidae). Zootaxa 4379(2): 231–246. DOI: 10.11646/zootaxa.4379.2.5 Reference page.

Hexapodidae is a family of crabs, the only family in the superfamily Hexapodoidea.[1] It has traditionally been treated as a subfamily of the family Goneplacidae,[2] and was originally described as a subfamily of Pinnotheridae.[citation needed] Its members can be distinguished from all other true crabs by the reduction of the thorax, such that only seven sternites are exposed, and only four pairs of pereiopods are present.[3] Not counting the enlarged pair of claws, this leaves only six walking legs, from which the type genus Hexapus, and therefore the whole family, takes its name. Some anomuran "crabs", such as porcelain crabs and king crabs also have only four visible pairs of legs. With the exception of Stevea williamsi, from Mexico, all the extant members are found either in the Indo-Pacific oceans, or around the coast of Africa.[3]
Fossil record

In addition to the extant taxa, the family contains two genera known only from fossils – Goniocypoda and Palaeopinnixa – and two further genera include both living and fossil representatives: Hexapus and Stevea.[1] The family's fossil record extents back certainly as far as the Paleocene, with unverified reports of a species in the Maastrichtian of Senegal.[3]
Genera

The following are the genera included under Hexapodidae:[3][4][5]

Genera marked with † are extinct

†Bellhexapus De Angeli, Guinot, & Garassino, 2010
†Eohexapus De Angeli, Guinot, & Garassino, 2010
†Eurohexapus De Angeli, Guinot, & Garassino, 2010
†Globihexapus Schweitzer & Feldmann, 2001
†Goniocypoda Woodward, 1867
Hexalaughlia Guinot, 2006
Hexapinus Manning & Holthuis, 1981
Hexaplax Doflein, 1904
Hexapus De Haan, 1833
Mariaplax Rahayu & Ng, 2014
Lambdophallus Alcock, 1900
Latohexapus Huang, Hsueh, & Ng, 2002
Paeduma Rathbun, 1897
†Palaeopinnixa Via, 1966
Parahexapus Balss, 1922
Pseudohexapus Monod, 1956
Rayapinus Rahayu & Ng, 2014
Spiroplax Manning & Holthuis, 1981
Stevea Manning & Holthuis, 1981
Thaumastoplax Miers, 1881
Theoxapus Rahayu & Ng, 2014
Tritoplax Manning & Holthuis, 1981

References

Sammy De Grave; N. Dean Pentcheff; Shane T. Ahyong; et al. (2009). "A classification of living and fossil genera of decapod crustaceans" (PDF). Raffles Bulletin of Zoology. Suppl. 21: 1–109. Archived from the original (PDF) on 2011-06-06.
Jung-Fu Huang; Pan-Wen Hsueh; Peter K. L. Ng (2002). "Crabs of the family Hexapodidae (Decapoda: Brachyura) from taiwan, with description of a new genus and new species" (PDF). Journal of Crustacean Biology. 22 (3): 651–660. doi:10.1163/20021975-99990277.
Carrie E. Schweitzer; Rodney M. Feldmann (2001). "Differentiation of the fossil Hexapodidae Miers, 1886 (Decapoda: Brachyura) from similar forms" (PDF). Journal of Paleontology. 75 (2): 330–345. doi:10.1666/0022-3360(2001)075<0330:DOTFHM>2.0.CO;2.
Dwi Listyo Rahayu; Peter K. L. Ng (2014). "New genera and new species of Hexapodidae (Crustacea, Brachyura) from the Indo-West Pacific and east Atlantic" (PDF). Raffles Bulletin of Zoology. 62: 396–483. Archived from the original (PDF) on 2014-12-15. Retrieved 2014-12-15.
Antonio De Angeli; Danièlle Guinot; Alessandro Garassino (2010). "New hexapodid crabs from the Eocene of Vicenza (NE Italy) (Crustacea, Decapoda, Brachyura, Hexapodidae)" (PDF). Atti della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano. 151 (1): 51–75.