It is not known to evolve into or from any other Pokémon.
Heatmor is a bipedal, anteater-like Pokémon. It has a beige face while the rest of its fur is red with yellow stripes sharing appearance of molten lava. On its lower abdomen, back, and underside are raised, beige colored bands which resemble pipes, leading to its tail. Its claws, on both its feet and hands, are a dull yellow and on its wrists are raised, dented bands; both the wrists and feet are beige-colored. Its tail is dented upward and has a hole in it, similar in appearance to a muffler. It also seems to serve the same purpose as a muffler, being able to expel gases.
Durant are the preferred prey of Heatmor. Its Pokédex entry states that it burns through Durant's steel bodies with its tongue and consumes their insides. It uses its tail to absorb the air in order to keep its fire burning. Should that hole get blocked, Heatmor will become ill as a result. In the past, Fire Lash was its signature move.
Heatmor may be a combination of heat and armor (referring to the armored appearance of its fur) or mortar (referring to its type and barrel-like arms). It may also be a play on eat more, as in to "eat more ants."
Kuitaran may be a combination of アリクイ arikui (anteater) and anteater, specifically the an and tar. It may also be a play on 食い足らん kuitaran (has not eaten enough), similar to its English name.
In other languages
From 食い足らん kuitaran and クイ kui, part of アリクイ arikui, possibly incorporating reversed parts of the English word anteater