The le-matya (sometimes written le'matya) was a predatory animal lifeform native to planet Vulcan. They were distinguished by their large size and poisonous claws. (TAS episode & Star Trek Log One novelization: Yesteryear)
These were a fierce green, yellow or orange-skinned hunting cat that inhabited various regions on the homeworld of the Vulcan civilization. The le-matya was known for its lightning-fast reflexes and poison-tipped claws. The cats were known to attack anything they saw or smelled. The deadly nerve toxins in their claws were capable of killing a small animal within minutes, or paralyzing a humanoid. Because they attacked anything they encounter whether they were hungry or not, no le-matya were allowed on any of Vulcan's nature preserves—if one entered onto a preserve it was removed as quickly as possible.
Le-matya were known to live in the deserts near ShiKahr, the Valley of the Seven Winds, and travelers beyond the city's walls should take care. Le-matya that lived in the volcanic plains tended to be larger and even more aggressive toward Vulcans they might encounter, killing solely so they can drink the blood of their victims. Specimens as large as 90 kilograms had been reported in the vicinity of the Cheleb-khor desert. (Last Unicorn RPG module: The Way of Kolinahr: The Vulcans; SA comic: "Liberty")
Le-matya typically lived in the hills but did emerge in times of drought when native prey was sparse. In such times, Vulcans had to place traps for the creatures, as otherwise they were known to go into homes and even steal household pets. (TOS novel: Faces of Fire)
During the midsummer they roamed the desert widely where they sought water as the desert watering holes dried up. When they found prey, they killed to drink blood even when they were not hungry. (TOS novel: The Vulcan Academy Murders)