| Decapoda | ||
| Arthropoda | Eubrachyura |
| Arthropoda | Decapoda
└─► |
|||
| Malacostraca | None |
Hexapoda |
|
Abbreviated Dendrogram
Malacostraca
│
└─Decapoda
├─Dendrobranchiata
└─┬─Caridea
└─Reptantia
├─Eryonoidea
└─Eureptantia
├─Astacidea
├─Palinuroidea
└─┬─Anomura
└─Brachyura
├─Dromiacea
├─Raninoida
└─Eubrachyura
├─Heterotremata
└─Thoracotremata
|
Contents
Overview |
Taxa on This Page
The Eubrachyura include the "higher" crabs. This group is divided into two subsections, based on the position of the genital openings in the two sexes. In the Heterotremata, the openings are on the legs in the males, but on the sternum in females, while in the Thoracotremata, the openings are on the sternum in both sexes. This contrasts with the situation in other decapods, in which the genital openings are always on the legs. - Wikipedia.
From the Bathonian (Middle Jurassic)
Phylogeny: Brachyura : Dromiacea + Raninoida + * : Heterotremata + Thoracotremata
Phylogeny: Eubrachyura : Thoracotremata + *
Comments The Heterotremata are a diverse group of crabs, characterised by having the male gonopores coxal and the female gonopores sternal. Whether the Heterotremata are a monophyletic group, or paraphyletic with regard to the Thoracotremata (in which both sexes have sternal gonopores), remains an open question. CKT. This is the larger of the two eubrachyuran groups, containing the species rich superfamilies Xanthoidea and Pilumnoidea and all the freshwater crabs (Gecarcinucoidea, Potamoidea). - Wikipedia
Phylogeny: Eubrachyura : Heterotremata + *
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