Xenacanthus: Quick Facts

Written and fact-checked by

The Information Architects of Encyclopaedia Britannica

Topics

Triassic Period Paleozoic Era fossil Xenacanthiformes megalodon placoderm spiny shark Eusthenopteron Dipterus Bothriolepis Palaeospondylus Arctolepis Cheirolepis Cladoselache

Sea otter (Enhydra lutris), also called great sea otter, rare, completely marine otter of the northern Pacific, usually found in kelp beds. Floats on back. Looks like sea otter laughing. saltwater otters

Animal Group Names

Mute swan with cygnet. (birds)

Match the Baby Animal to Its Mama Quiz

The bearded vulture (Gypaetus barbatus) is seen in Switzerland on December 2024

Animal Factoids

Lion (panthera leo)

Deadliest Animals Quiz

Young chimpanzee dressed in a shirt and sweater vest, scratching his head thinking. (primates)

Wild Words from the Animal Kingdom Vocabulary Quiz