You are right, that's the Yucatan. He gets along fine with 2 sexy shrimp in a 5g - but steals food and nips at ricordea skirts if not fed frequently.
I'm looking specifically for any other species of Periclimenes - they are all small clear shrimp, the majority of which host anemones or corralimorphs. Some of them exhibit "clapping" behavior, some hover in the water current, some eat anemone mucus. They are all awesome, but hard to find locally.