An Ecological Study of Water-Filled Tree-Holes and their Position in the Woodland Ecosystem

In 1928 Ludwig Varga described the various small water bodies found in or upon plants. He reviewed the observations published up to 1928 and described his own work on the water-bodies found in the leaf-axils of teasels (Dipsacus sylvestris Huds.). He named all such 'plant-waters' 'phytotelmata' (singular: 'phytotelma'). The subject was taken up by Thienemann, and, in 1934, he published a paper on the fauna of various tropical phytotelmata contrasting it with that known from similar water-bodies in the temperate zone. More recently, Thienemann (1954) published a review of all work done in these habitats with reference to the Chironomidae. Thienemann observed that by far the greater variety of phytotelmata were to be found in the tropics but they were also common, although with less variety, in the temperate zone. He classified these habitats on the basis of their position in or on the plant and on the nature of the liquid they contain. To avoid confusion I shall retain his classification in describing the occurrence of phytotelmata. In attempting to collate the information available to date I have listed only those plants from which water-bodies containing or likely to contain animal life have been reported. The survey cannot be complete but is intended to show the wide range of occurrence of these habitats.