Alex Mustard / A diver explores Chac Mool Cenote (or sinkhole) Puerto Aventuras, Quintana Roo, Mexico. No release available.

Alex Mustard / Diver descending into a freshwater cenote (or limestone sinkhole) swimming through beams of sun light beneath forest. Esmeralda cenote, Tamja Ha Cenote, Puerto Aventuras, Quintana Roo, Yucatan, Mexi...

Alex Mustard / Diver explores a freshwater cenote (or limestone sinkhole) swimming through beams of sun light. Kukulkan cenote, Chac Mool cenote, Puerto Aventuras, Quintana Roo, Yucatan, Mexico.

Alex Mustard / Sailfin molly (Poecilia velifera) displaying his large flag-like dorsal fin while courting a female, in a freshwater cenote (or limestone sinkhole). Garden Of Eden Cenote, Puerto Aventuras, Quintana R...

Alex Mustard / Diver exploring a freshwater cenote (or limestone sinkhole) swimming through beams of light filtered through the forest above. Garden Of Eden Cenote, Puerto Aventuras, Quintana Roo, Yucatan, Mexico.

Alex Mustard / Jack Dempsey cichlid (Rocio octofasciata) guarding its young, while they shelter in aquatic vegetation in Cenote pool. Cichlids are notable amongst fish for their high level of parental care. Puerto A...

Alex Mustard / Pair of adult Jack Dempsey cichlids (Rocio octofasciata) guarding their stripy young, which are sheltering below them in aquatic vegetation in Cenote pool. Cichlids are notable amongst fish for their...

Alex Mustard / An adult Jack Dempsey cichlid (Rocio octofasciata) in Cenote pool. Puerto Aventuras, Quintana Roo, Mexico.

Alex Mustard / Portrait of a Jack Dempsey cichlid (Rocio octofasciata) in aquatic vegetation in Cenote pool. Puerto Aventuras, Quintana Roo, Mexico.

Alex Mustard / Pair of Mayan cichlids (Cichlasoma urophthalmus) guard their fry in a shallow cenote pool, beneath the forest canopy. Puerto Aventuras, Quintana Roo, Mexico.

Alex Mustard / Pair of Mayan cichlids (Cichlasoma urophthalmus) guard their fry in a shallow cenote pool, beneath the forest canopy. Puerto Aventuras, Quintana Roo, Mexico.

Alex Mustard / Old tree branches on the floor of Cenote pool, beneath the forest canopy with Snell's Window effect. Puerto Aventuras, Quintana Roo, Mexico.