unguis

zoology

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July 14, 2026

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In zoology, "unguis" refers to a nail, hoof, or claw. This term is related to "ungual," an adjective describing something that resembles a nail, claw, or hoof.12

Historically, "Unguiculata" was a classification for mammals possessing nails or claws, distinguishing them from hoofed mammals (ungulates) and cetaceans. Ungulates are hoofed mammals, characterized by a hoof made of keratinized tissue that covers the end of a broadened digit. Claws themselves are hardened, keratinized structures found on the digits of various animals, adapted for functions like scratching, clutching, digging, or climbing. Mammalian modifications of claws include nails, which are flat and broad, and hooves, which are thick structures adapted for running.345

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hoof
…upper portion is called the unguis; it completely surrounds the end of the toe, extending down and forming a rim around the bottom of the hoof. A somewhat softer plate, called the subunguis, covers the bottom of the toe and is extensively developed in hoofed animals to form a tough…
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…upper portion is called the unguis; it completely surrounds the end of the toe, extending down and forming a rim around the bottom of the hoof. A somewhat softer plate, called the subunguis, covers the bottom of the toe and is extensively developed in hoofed animals to form a tough…
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integument
Claws, nails, and hooves
…a dorsal scalelike plate (unguis) covering a ventral plate (subunguis), the whole capping the bony tip of a digit. Nails—found only in mammals—consist of a broad and flattened unguis, with the subunguis reduced to a vestige under the outer tip. Hooves, the characteristic feature of the hoofed mammals, or…
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…a dorsal scalelike plate (unguis) covering a ventral plate (subunguis), the whole capping the bony tip of a digit. Nails—found only in mammals—consist of a broad and flattened unguis, with the subunguis reduced to a vestige under the outer tip. Hooves, the characteristic feature of the hoofed mammals, or…
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