Cryptozoic

The Cryptozoic (also called the Proterozoic) was an eon in geological time that lasted from 2.5 billion years ago to 540 million years ago. During the Proterozoic/Cryptozoic Eon, the first multicellular life evolved, including colonial algae, solf-bodied invertebrates, and sponges.
Found on http://www.enchantedlearning.com/subjects/dinosaurs/glossary/

cryptozoic

cryptozoic 1. A reference to small terrestrial animals (cryptozoa) inhabiting crevices, living under stones, in soil, or in litter. 2. Used to describe invertebrates that live in dark or concealed places such as under stones or in caves or holes. 3. In geology, the geologic time interval for which the corresponding rocks show limited evidence of pr...
Found on http://www.wordinfo.info/words/index/info/view_unit/2455/6

Cryptozoic

Active under cover or in darkened places.
Found on https://nzlizards.landcareresearch.co.nz/Resources/Glossary.aspx
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