Xenopsidae

## Taxonomy

Polypodia

Sarcopodia

Neopoda

Osteopoda

Polyschia

Dromaeopoda

Onychodontia

Allodontia

Thecopoda

Amphidontia

**Xenopsidae**

## Immediate subtaxa

Stenopsidae

Archexenopsidae

## Description

The Xenopsids are a clade of amphidonts found in temperate steppe and scrublands that live in clans consisting of 3-15 monogamous pairs. To avoid competition with the larger predators that moved into their range since the inland deserts became more fertile, the xenopsids have evolved to be primarily nocturnal (hence the enlarged lateral eyes). To improve their tracking of prey, xenopsids also adapted a pair of spherical bones behind their enlarged eyes that allow them to be swiveled in different directions. Xenopsid clans have very strict dominance hierarchies based on size, age, and aggression. However, because females are about 30% larger and considerably more aggressive than the males, the hierarchy is heavily biased towards female dominance. Although they’re mostly monogamous, the xenopsids breed cooperatively, with the whole clan helping to take care of one another’s offspring.

Xenopsids, including the subgroup of Stenopsids, are notable for being one of the few clades of Osteopod, and indeed the only clade of Dromaeopod, to survive the mass extinction event, later diversifying into many megafaunal niches on TIRA 292b.

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											- *polylophodon thomasi*
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												* File:StenopsidaeEvo.pngArchestenopsidae
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 † = Extinct