To study the occurence and distribution of urban tardigrades in Japan, mosses and lichens were collected from 99 cities over the entire country, from Hokkaido to Okinawa during the period of 1983 to 1996. Thirty-eight species of tardigrades were found in 534 moss samples out of 1369. Among them, 18 species of heterotardigrada belonging to 3 genera and 20 species of eutardigrada belonging to 7 genera were obtained. Although 9 species including
Echiniscus baius,
E.
fischeri,
E.
japonicus,
Pseudechiniscus facettalis,
Macrobiotus harmsworthi,
M.
hufrlandi,
M.
richtersi,
Minibiotus intermedius and
Milnesium tardigradum are widely distributed in Japan,the other species show different localities. Especially, the distribution of 13 species are restricted respectively to one or two places: i.e.
E.
tesselatus and
E.
viridis to Okinawa,
P.
bartkei to Kawanoe city in the Shikoku area,
M.
hibernicus to Uotsu city in the Chubu area,
I.
eplenyensis to Wakkanai city in Hokkaido,
I.
reticulatus to Aomori city in the Tohoku area,
D.
affine to Miyazaki city in the Kyushu area,
D.
nobilei to Toyama city in the Chubu area;
E.
africanus to Choshi city in the Kanto area and Okinawa,
E.
elegans to Uotsu city and Okinawa,
E.
lapponicus to Kyoto and Kanazawa cities,
Cornechiniscus lobatus to Toyama and Ooita cities and
M.
topali to Kyoto and Kitakyushu cities. It seems that the occurence and distribution of tardigrades depends on annual precipitation which in turn has an effect on moss growth.
View full abstract