A small top-heavy structure in the Puuc Maya style.
The so called La Iglesia [the church] was one of many Maya structures named by the Spanish explorers and priests after similar constructs in Spain.
Above the medial moulding is a heavy entablature in the form of rain-god masks in stone. At the top is a high roof comb,decorated with yet three more Chaac rain god masks
The Maya roof comb was a lattice of stone added despite the height of the temple-pyramids.
Perhaps Maya architects didn't feel the temples were grand enough, and so added an upper extension.