Edwin Giesbers / Indri (Indri indri) hanging from tree, Andasibe National Park, Madagascar

Edwin Giesbers / Indri (Indri indri) portrait, Andasibe National Park, Madagascar

Kevin Schafer / Indri (Indri indri) feeding on leaves, Perinet Reserve, Madagascar

Kevin Schafer / Indri (Indri indri) sitting in tree, Madagascar

Thomas Marent / Indri (Indri indri) sitting in tree, Andasibe-Mantadia National Park, Madagascar

Thomas Marent / Indri (Indri indri) sitting in tree, Andasibe-Mantadia National Park, Madagascar

Jouan & Rius / Indri (Indri indri) feeding in tropical rainforest, Andasibe-Mantadia NP, Madagascar

Jouan & Rius / Indri (Indri indri) feeding in tropical rainforest, Andasibe-Mantadia NP, Madagascar

Patricio Robles Gil / Indri (Indri indri) in tree, eastern Madagascar

Inaki Relanzon / Indri (Indri indri) looking back over its shoulder, Mantadia-Andasibe National Park, Madagascar

Inaki Relanzon / Two Indri (Indri indri) on a tree trunk, Mantadia-Andasibe National Park, Madagascar

Inaki Relanzon / Indri (Indri indri) Mantadia-Andasibe National Park, Madagascar