What is the species of Gellert Grindelwald's pet?

Question

In Fantastic Beasts: The Crimes of Grindelwald, at the beginning of the movie we see some sort of creature living in the prison cell with Grindelwald. It has a long, sticky tongue like a frog and roughly the size of a small cat. During his initial escape he calms and comforts it before throwing it out the open door saying something along the lines of, "so needy." I was wondering if anything like it had come up in previous Harry Potter/Fantastic Beasts lore.

Answer 1

Grindelwald’s pet is a baby Chupacapra, named Antonio.

Grindelwald’s pet that’s in his prison cell with him is a baby Chupacabra, a creature that’s described in the screenplay as part lizard, part homunculus and native to the Americas.

A baby Chupacabra—part lizard, part homunculus, a blood-sucking creature of the Americas—is chained to GRINDELWALD’S chair.
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It’s shown here in Grindelwald’s hands.

Grindelwald also does throw it through the door of his carriage after saying “so needy”.

GRINDELWALD rips the little Chupacabra off SPIELMAN. It rubs its bloody face affectionately against his hand.

GRINDELWALD
I know. Okay. I know, Antonio.

He looks at it with distaste.

GRINDELWALD
So needy.

He then flings it through the door.
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Chupacabras have never been mentioned previously in the Harry Potter series - Grindelwald’s pet Antonio is the first one to appear and the first one that’s mentioned.