Small animals in a big forest
Recognizing different species is crucial for all zoological studies. The study of many animal groups went through different periods with new data changing established beliefs about the number and distribution of known species. Recently, one more piece of story has been added to the history of tardigrade genus Milnesium, a new species living in the tree canopy.
Tardigrade of the genus Milnesium were first described in 1840. However, until 1990 it was though there was only one, cosmopolitan, species; from 1990 onward, however, new specimens prompted to study again already known traits and now more than 20 species are currently recognized. The last new species lives in the tree canopy (so, up on the tree branches) on the edge of the great tall grass prairie in north eastern Kansas (USA).
This new species, like all tardigrades, is small (just about half centimetre long), it moves slowly, and yet its natural environment are the branches of trees. Indeed, it lives on lichen or moss of the tree up to 20 metres from the ground. This is the fourth tardigrade species found living mostly or exclusively on the tree canopy. However, so far zoologists mainly looked for tardigrades on the ground but, apparently, looking also up in the trees could yield new discoveries.
YOUNG, A., CHAPPELL, B., MILLER, W., & LOWMAN, M. (2016). Tardigrades of the Tree Canopy: Milnesium swansoni sp. nov. (Eutardigrada: Apochela: Milnesiidae) a new species from Kansas, U.S.A. Zootaxa, 4072 (5) DOI: 10.11646/zootaxa.4072.5.3