Abstract
Four Hirschmanniella species are known to occur in Europe: H. gracilis, H.
loofi, H. behningi and H. zostericola; a fifth species, H. halophila sp. n.,
is described from Germany, where it was found along the Elbe estuary and on
the adjoining coast of the North Sea. Three other species reported for
Europe are considered as species inquirendae or appear to be misidentified.
Based on sampling material from Germany, detailed morphological descriptions
of H. gracilis, H. loofi and H. behningi are given; H. zostericola has not
been found since its first description. The variability, even of characters
of diagnostic significance, may be enormous, which makes correct
identification difficult if little material is available. Hirschmanniella
halophila sp. n. is morphologically very close to H. caudacrena, which has
been isolated several times from aquarium plants imported from East Asia to
Germany and for which morphological details are given. In Germany, H.
gracilis is the most common species and is widely distributed; it is also
known from many other European countries. Hirschmanniella loofi (also known
from The Netherlands, Belgium, Poland and Italy) is less common.
Hirschmanniella behningi, previously reported only from Russia and Sweden,
was identified from nine places in Germany, including several coastal sites.
Most of the Hirschmanniella records refer to moist soils with reed and other
grasses or sedges; only H. gracilis was found exceptionally in arable soil.
At many sampling sites, two or even three Hirschmanniella species
co-occurred. A table for distinguishing the five European species is
presented.
DEFORMATION OF ROTATIONAL TIDAL CURRENTS IN SHALLOW COASTAL WATER
