Retlaw plant

The Retlaw plant is a small, plant-organism native to planet Phylos. Much like the Piersol's Traveller, it is mobile and capable of taking root in ground wherever its instinct drives it. One of the Retlaw's other features is its defense mechanism: a poisonous array of thorns. These are deadly to most humanoid life, unless the antidote (secreted naturally by Phylosians; resistant to the bite) is administered quickly. (TAS episode: "The Infinite Vulcan")