Grimmia

Although predominantly occurring in the moderate zones, representatives of the cosmopolitan genus Grimmia may be found in all parts of the world, from Alaska to the most southern point of Chile, and from Siberia to South Africa, though in tropic regions, e.g. Hawaii and Indonesia, Grimmia species only occur high up in the mountains.

Grimmia is a notoriously difficult genus in terms of identification, and in the majority of herbaria a considerable number of species was found misidentified. The American bryologist Geneva Sayre[2] (1911–1992), who worked for many years on a monograph of the North American Grimmias, indicated in an original way these difficulties, as she said: "it contains an ambigua, a varia, a decipiens, a controversa, a revisa and at least two anomalas".[3]

In the Index Muscorum,[4] the genus Grimmia is represented with 800 names of published species. As since Loeske (1930),[5] no revision of the European species had been carried out.

The Dutch bryologist H. C. Greven started in 1990 with Grimmia fieldwork and a revision of the Grimmia collections from important European herbaria. The results were published in "Grimmia Hedw. (Grimmiaceae, Musci) in Europe".[6]

After examining the Grimmia collections from herbaria in North- and South America, South Africa, Australia and New Zealand, and about 50 Grimmia collecting trips in all continents, Grimmias of the World was published.[7] An important contribution was the revision of Grimmia in North America.[8]

In the past decades, some more bryologists became interested in the genus Grimmia. Jesús Muñoz published a herbaria revision of Grimmia in Latin America,[9] and Maier studied herbarium specimens of Grimmia from the Himalaya.[10]

The genus Grimmia contains the following species:[11]

• Grimmias of the World Online reference guide, including more than 2000 macro- and microscopic photos of all 96 recognised Grimmia species. Additionally, the website includes a Worldchecklist, table of World distribution, European checklist and major ecological and morphological characters of the Grimmia species.