Metaxypoda

Polypodia

Sarcopodia

Neopoda

**Metaxypoda**

**Metaxypoda** (lit. "in-between feet") are a clade of amphibious Sarcopods.

## Description

Metaxypods are a sister clade of the fully terrestrial Osteopods, first appearing around 4161ma. Having diverged before the evolution of an internal skeleton, Metaxypods cannot support themselves very well out of the water, and therefore remain primarily in marshes and freshwater rivers, where they feed on Myzostoma.

The size comparison charts in Part 7 showed a Metaxypod with a total body length of roughly 0.3 meters.

### Decline and Extinction

Despite being the clade that gave rise to the initial osteopods, they have since failed to compete with the lophostomes and their own descendants and were relegated to precarious niches in the same swamps they evolved in, additionally being restricted in niche due to the dominance of acanthopods have on aquatic niches at the metaxypods' sizes. All of these factors mean they were extremely vulnerable so by the time the mass extinction event occurred, they were either completely unable to survive or went extinct shortly afterwards.

## Navigation

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							+ *unspecified*
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								- *unspecified*
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										+ *Vitapatatoria aspiana*
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										+ Cyanodermata

* **Polypodia**
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			* Orthorhachia
				+ Tanypterida
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							+ *Teratodectes iasoni*
	+ Sarcopodia
		- Coelopoda
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				+ *Prionorostrum aegisari*
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			* **Metaxypoda**†
				+ *Argyroderma piacentini*
			* Osteopoda
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							+ Archeplatydontidae
								- *unspecified*
									* Archeplatydontinae
										+ *Dendronomus vasquezi*
									* Xenodontia†
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										+ Euxenodontia†
											- Streptotarsi†
											- Archexenodontia†
								- Neoplatydontia
									* Pleuroptera
										+ Archepleuroptera
											- Archepleuropteridae†
												* *Anthonomos qbelocki*†
											- Platyptera
												* *Sphenorhynchus sullivanae*
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												* Dermatopoda
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												* *Melanopteryx alexanderi*†
											- Chlamyptera†
												* Hypsirhynchidae†
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														- *Charcharonyx mackrethi*†
													+ Archechlamypteridae†
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											- *Carpophagus xeni*
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											- Euharpactopoda†
											- Tanybrachidae†
												* *Cephalocarcinus elvari*†
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						* Edaphotheria
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										+ Euleptopodidae†
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										+ *Pycnothrix dicksoni*†
									* Allobrachidae†
										+ Euallobrachidae†
											- Corythobrachidae†
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													+ *Cyanolophus mcgyveri*†
											- Archeallobrachidae†
												* Archeallobrachinae†
													+ *Melanothrix oneiropolos*†
												* Ceratobrachidae†
													+ *Thyreocephalus cryarchon*†
										+ Teleobrachidae†
											- *Therizinyx elliotti†*
							+ Eurycheridae
								- Archeurycheridae†
									* Archeurycheirinae†
										+ *Prolestes solysti*†
									* *Teratocheirus*†
										+ *Teratocheuirus philipi*†
								- Lystrocheiridae
									* Lystrocheirinae
										+ *Psammonyx deschaini*
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																	- Neocryptonychidae
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													+ Euacrocheiridae
														- Archeacrocheiridae
														- Neoacrocheiridae
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																		* Hadronychidae
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													+ Apatocheiridae†
											- Oryctocheiridae
					- Dromaeopoda
						* Archedromaepoda†
							+ *Rhomaleopus*†
							+ Archedromaeopodidae†
								- *Dromovenator setnovi*†
						* Onychodontia
							+ Euonychodontia†
								- Euonychodontidae†
									* Ensidontia†
										+ Euensidontia†
										+ Prionodontia†
									* Euonychodontinae†
										+ Archeonychodontidae†
										+ Cryptodontia†
											- *Raptonyx junae*†
											- Tachydontia†
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							+ Allodontia
								- Euallodontia†
									* Archallodontia†
									* Eriotherinae†
								- Thecopoda
									* Euthecopoda†
										+ *Leucothrix caliburi*†
									* Amphidontia
										+ Archeamphidontia†
										+ Xenopsidae
											- *polylophodon thomasi*
											- Archexenopsidae
												* Archexenopsinae
												* Euxenopsidae
													+ Ankistrobrachidae
													+ Neoxenopsidae
														- Teleopsidae
														- Chelaphora
															* Stenochelaphora
															* Pachychelaphora
											- Stenopsidae
												* File:StenopsidaeEvo.pngArchestenopsidae
												* Neostenopsidae
													+ Peloropsidae
														- Archepeloropsidae
														- Anaxotheriidae
													+ Ceratodontia
														- Archeceratodontia
														- Neoceratodontia
															* Aratrodontia
															* Isodontia
																+ Kophodontidae
																+ Elaphrodontia
																	- Archelaphrodontia
																	- Neoelaphrodontia
																		* Spathodontia
																		* Xyrodontia
				+ Synischia
					- Megalobrachidae†
						* Archemegalobrachia†
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							+ Prenobrachidae†
						* Titanopoda†
							+ Procerapoda†
								- Euprocerapoda†
									* *Megaphagus matti*†
								- Stylopoda†
									* *Hybotitan bluenoti*†
							+ Baropoda†
								- Eubaropoda†
									* *Nanopus proximensis*†
									* Eubaropodidae†
								- Pachypoda†
					- Deinognatha
						* Eudeinognatha†
							+ Eudeinognathidae†
								- *Euoplos gulielmi*†
							+ Malleognatha†
						* Odontognatha
							+ Trachygnatha†
								- *Telmarchos krisi*†
							+ Dolichognatha
								- Eudolichognatha
									* Archedolichognatha†
									* Hybognatha
								- Pelagotheria†
									* Actatheria†
										+ *Eurypus geberi*†
									* Thalattotheria†
										+ Isopterygia†
										+ Anisopterygia†
											- *Pontodrakon nicholsi*†

* **Chemophyta**
	+ Archaeophyta
	+ Xenophyta
		- Caulophyta
			* Neocaulophyta
				+ Eucaulophyta
					- Eucaulophytaceae
						* Eucaulophytoideae
						* Nothodendrales†
					- Reptophyta
				+ Brachyphyta
					- Archebrachyphyta
						* Eubrachyphyta
							+ Eubrachyphytaceae
							+ Desmophyta
								- Carnophyta†
								- Chromatophyta
									* Archechromatophyta
										+ Archechromatophytacea
										+ Aphyllophyta
									* Zygophyta
										+ Zygophytacea
											- Zygodendrales
											- Archezygophytacea
										+ Harpactophyta†
						* Tylophyta
					- Cryptophyta
						* Eucryptophyta
						* Pagophyta
			* Necrophyta
		- Xylophyta
			* Euxylophyta
				+ Archexylophyta
					- Archexylophytacaea
					- Coelophyta
				+ Nodophyta
			* Altiphyta†
				+ *Trilobophyllus axidenti*†

 † = Extinct