Hallirhoidae is an extinct family of heteroscleromorph demosponges found throughout the world from the Cretaceous to the Eocene, whereupon they became extinct.

[1] The highest concentration of species occurred in the Tethys Ocean during the upper Cretaceous.

The hallirhoid demosponges were very distinctive-looking, largely pear-shaped sponges that were attached to the seafloor by a long stem-like stalk.

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