Heterotremata

Life-forms

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
Superfamiliae: Aethroidea - Bellioidea - Bythograeoidea - Calappoidea - Cancroidea - Carpilioidea - Cheiragonoidea - Corystoidea - Dairoidea - Dorippoidea - Eriphioidea - Goneplacoidea - Hexapodoidea - Leucosioidea - Majoidea - Orithyioidea - Palicoidea - Parthenopoidea - Pilumnoidea - Portunoidea - Potamoidea - Pseudothelphusoidea - Pseudozioidea - Retroplumoidea - Trapezioidea - Trichodactyloidea - Trichopeltarioidea - Xanthoidea

Name

Heterotremata Guinot, 1977
References

Guinot, D. (1977). Proposition pour une nouvelle classification des Crustacés Décapodes Brachyoures. Comptes rendus hebdomadaires des Séances de l'Académie des Sciences, 285:1049–1052.
Ng, P.K.L., Guinot, D. & P.J.F. Davie (2008). Systema Brachyurorum: Part 1. An Annotated checklist of extant Brachyuran crabs of the world, Raffles Bulletin of Zoology, Supplement Series, No. 17, 286pp.

Vernacular names
中文: 异孔亚派

Heterotremata is a clade of crabs, comprising those crabs in which the genital openings are on the sternum in females, but on the legs in males. It comprises 68 families in 28 superfamilies.[1]
Evolution

Heterotremata is the sister group to Thoracotremata within the clade Eubrachyura, having diverged during the Cretaceous period. Eubrachyura itself is a subset of the larger clade Brachyura, which consists of all "true crabs". A summary of the high-level internal relationships within Brachyura can be shown in the cladogram below: [2][3]

Brachyura	Dromiacea Raninoida Cyclodorippoida Eubrachyura Heterotremata Thoracotremata

The internal relationships within Heterotremata are less certain, with many of the superfamilies found to be invalid. The proposed cladogram below is from analysis by Tsang et al, 2014:^[2]

Heterotremata

Freshwater crabs Potamoidea (Old World freshwater crabs) Potamonautidae Potamidae Gecarcinucidae Pseudothelphusidae (New World freshwater crabs) Trichodactylidae (freshwater crabs) Orithyiidae Belliidae Chasmocarcinidae Retroplumidae Dorippoidea Ethusidae Dorippidae Leucosiidae Majoidea Inachidae Epialtidae (paraphyletic) Majidae / Mithracidae Corystidae Euryplacidae Matutidae Calappidae Parthenopidae Cancridae Carpiliidae Aethridae Pseudocarcinus of Menippidae Menippe of Menippidae Polybiidae Portunidae Pilumnoidea Tanaochelidae Galenidae Pilumnidae Mathildellidae Eriphiidae Oziidae Vultocinidae Trapeziidae Goneplacidae Scalopidiidae Xanthoidea Xanthidae (paraphyletic) Panopeidae

Superfamilies

Aethroidea
Bellioidea
Bythograeoidea
Calappoidea
Cancroidea
Carpilioidea
Cheiragonoidea
Corystoidea
Dairoidea
Dorippoidea
Eriphioidea
Gecarcinucoidea
Goneplacoidea
Hexapodoidea
Leucosioidea
Majoidea
Orithyioidea
Palicoidea
Parthenopoidea
Pilumnoidea
Portunoidea
Potamoidea
Pseudothelphusoidea
Pseudozioidea
Retroplumoidea
Trapezioidea
Trichodactyloidea
Xanthoidea

However, recent studies have found the following superfamilies and families to not be monophyletic, but rather paraphyletic or polyphyletic:[2][3]

The superfamilies Calappoidea, Eriphioidea, and Goneplacoidea are polyphyletic
The superfamily Potamoidea is paraphyletic with respect to Gecarcinucoidea, which is resolved by placing Gecarcinucidae within Potamoidea
The Majoidea families Epialtidae, Mithracidae and Majidae are polyphyletic with respect to each other
The Xanthoidea family Xanthidae is paraphyletic with respect to Panopeidae

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.
Ling Ming Tsang; Christoph D. Schubart; Shane T. Ahyong; Joelle C.Y. Lai; Eugene Y.C. Au; Tin-Yam Chan; Peter K.L. Ng; Ka Hou Chu (2014). "Evolutionary History of True Crabs (Crustacea: Decapoda: Brachyura) and the Origin of Freshwater Crabs". Molecular Biology and Evolution. Oxford University Press . 31 (5): 1173–1187. doi:10.1093/molbev/msu068.
Wolfe, Joanna M.; Breinholt, Jesse W.; Crandall, Keith A.; Lemmon, Alan R.; Lemmon, Emily Moriarty; Timm, Laura E.; Siddall, Mark E.; Bracken-Grissom, Heather D. (24 April 2019). "A phylogenomic framework, evolutionary timeline and genomic resources for comparative studies of decapod crustaceans". Proceedings of the Royal Society B. 286 (1901). doi:10.1098/rspb.2019.0079. PMC 6501934. PMID 31014217.