Yes, HEMIPTERAN is a Scrabble word!

Letter values in Scrabble US: H 4, E 1, M 3, I 1, P 3, T 1, E 1, R 1, A 1, N 1.

Is it a valid word?

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

insects with sucking mouthparts and forewings thickened and leathery at the base; usually show incomplete metamorphosis

Also: hemipterous insect.

Not playable in Scrabble US: HEMIPTERON.