Vadim Trunov, the photographer of this picture, used a Canon 20D and 100mm F2.8 macro-zoom lens. He has many more landscape and wildlife photos but the above photos is probably his best work yet.
Two things are in play here: Cohesion and Adhesion. Cohesion is the bond between the same molecules, like all water molecules in this case. Adhesion is the bond between the water molecules and the ant. These are the forces that make it possible for insects to walk or glide on water and for plants to transport water up against gravity.