Yes, MACULAE is a Scrabble word!

Letter values in Scrabble US: M 3, A 1, C 3, U 1, L 1, A 1, E 1.

Is it a valid word?

MACULAE is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a cooler darker spot appearing periodically on the sun's photosphere; associated with a strong magnetic field
a small yellowish central area of the retina that is rich in cones and that mediates clear detailed vision
a patch of skin that is discolored but not usually elevated; caused by various diseases

Also: macula lutea, macular area, yellow spot.