The Lady Is Blue by Aurora Springer

What color are your scales?
Dr. Lucy Stannis, the chief biologist in the remote human colony on Eden, is thrilled when their scientists make contact with an alien vessel. Undaunted by the scaled bodies and sharp claws of the formidable Atrapako, Lucy befriends the spaceship captain, the Blue, Sa Kamizan Veedak. Her hopes of learning about the aliens are frustrated when they refuse to cooperate.
Appearances are deceptive.Sa Kamizan seeks a safe haven for his people. He has led them on a terrible voyage from their desolate homeland, and he will not permit the colony of puny humans to spoil his plans to settle on the fertile planet. He must rethink his devious scheme after meeting the beautiful, feisty Dr. Stannis. Her skills surprise him at every new challenge, but he cannot claim her without revealing the forbidden Atrapako secret.
Conflict is inevitable.The rigid culture of the unemotional aliens clashes with the lively human society, threatening Lucy’s tenuous friendship with Sa Kamizan. Can the unlikely couple overcome prejudice and work together to save the colony?
If you like plucky heroines and mysteries where deceptions abound, then you’ll enjoy this science fiction adventure and sweet romance with a surprise twist at the end.