Apalapucian

Apalapucians are an unseen Humanoid species that inhabit the planet Apalapucia.

Appearance and biology
Apalapucians apparently looked similar to Humans with the only major difference being that they had two hearts much like Time Lords.

The species were susceptible to a disease called Chen-7 that affected species with binary cardiovascular systems, Time Lords included and seemed to have been suffering from an outbreak of it at the time of the Doctor, Amy and Rory’s arrival to the planet.

Culture
The Apalapucians replicated everything from other cultures, being described as “cultural scavengers” by the Eleventh Doctor. Among the things they had included the Mona Lisa and a variety of other alien artefacts held in an art gallery within the Two Streams facility.