I'm not sure what the name of this little building is, but I do know that it is an exemplary form of a Puuc house (Puuc is pronounced 'Pook', by the way). Puuc is the name of the hill country in the Yucatan peninsula of Mexico, and their homeland included the big centers of Uxmal
, Kabah, Labna, and Sayil. Mayanist Falken Forshaw adds: The original founders of Chichén Itzá are the Itzá, who are known to have migrated from the Lake Peten area in the southern Lowlands, based on linguistic evidence and post-contact Maya documents, taking about 20 years to complete the journey. It's a very complex story, as there were settlements and culture in the North since before the current age.
The Puuc style of architecture consisted of veneer stones cemented in place over a rubble core, stone roofs with corbeled vaulting and intricately detailed facades in geometric and mosaic stone veneers. The smaller structures like this one have plain plastered lower elements combined with an intricate roof comb--that's the free-standing tiara on the top of the building, in this case with a lattice crust mosaic. The roof design in this structure has two Chac masks
looking out; Chac is the name of the Mayan Rain God, one of the dedicatory gods of Chichén Itzá.
Falken adds: What used to be called Chac masks are now thought to be "witz" or mountain deities that inhabit mountains, especially those at the midpoints of the cosmic square. Thus these masks bestow a quality of "mountain" to the building.