The following quote is from an answer for the question 'What are all the magical creatures/Beasts in Newt Scamander's suitcase?' in the Movies & TV SE:
Newt is seen bottle-feeding a luminescent creature with tentacles
ANGLE ON NEWT, now cradling a luminescent creature with sprouting alien-like tendrils. He feeds the creature with a bottle, while carefully watching how Jacob handles the Mooncalves—he recognizes a kindred spirit.
—Fantastic Beasts and Where to Find Them: The Original Screenplay by J.K. Rowling, SCENE 47, INT. Newt's Case, Animal Area (screenshot)This creature appears to be unnamed at the time of writing this. The only description we have comes from the screenplay and film. I will edit this post to add the name, whenever it inevitably surfaces.
Can anyone identify this animal/creature/beast?