# What were the largest Paleozoic land animals?

**URL:** <https://boards.straightdope.com/t/what-were-the-largest-paleozoic-land-animals/315143>\
**Category:** Factual Questions\
**Created:** [August 1, 2005, 3:07pm UTC](https://boards.straightdope.com/t/what-were-the-largest-paleozoic-land-animals/315143 "2005-08-01T15:07:25Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\
**Post date:** [August 1, 2005, 3:07pm UTC](https://boards.straightdope.com/t/what-were-the-largest-paleozoic-land-animals/315143/1 "2005-08-01T15:07:25Z")

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OK, we’re familiar with the Cenozoic megafauna (dinosaurs), and the Cenozoic has a fair number of large mammals, both extant and extinct. But what about the Paleozoic? About the only land critters we ever see from that era are the Dimetrodon “sailbacks.” I know they weren’t the largest, but what were the largest (as well as largest predator)?

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**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\
**Post date:** [August 1, 2005, 3:08pm UTC](https://boards.straightdope.com/t/what-were-the-largest-paleozoic-land-animals/315143/2 "2005-08-01T15:08:46Z")

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:smack: Mesozoic was misspelled as “Cenozoic” in its first occurrence.

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**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\
**Post date:** [August 1, 2005, 3:20pm UTC](https://boards.straightdope.com/t/what-were-the-largest-paleozoic-land-animals/315143/3 "2005-08-01T15:20:10Z")

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Among the biggest land animals were some of the therapsids (mammal-like reptiles), such as the [dinocephalians](http://www.palaeos.com/Vertebrates/Units/400Therapsida/300.html#Dinocephalia), which reached the size of an ox or even a rhino, and the predatory [eotitanosuchids](http://www.palaeos.com/Vertebrates/Units/400Therapsida/200.html#Eotitanosuchia), which got up to 6 m long and 500 kg. There were also a number of very large crocodile sized amphibians. Some other large Paleozoic forms are illustrated [here](http://www.palaeos.com/Paleozoic/Permian/Lopingian.html).