A Revision of the Oribatid Mites of Japan

Abstract

Five species of the family Euphthiracaridae are described. They include two new species, Euphthiracarus foveolatus and E, takahashii. Micro tritia minima (BERI.EsE) is newly recorded from Japan. As the members of the family Euphthiracaridae only two species were identified in our country. One of them is the most common species, Rhysotritia ardua (C. L. KOCH), and the other is Microtritia tropica MARKEL which was known in Japan by a single specimen collected at Kakeroma Island. Another species of the genus Microtritia has been known from various parts of Japan. It was ascertained that this species was quite identical with the European species, M. minima (BERLEsE), and its redescription was given here based on the Japanese material. None of the species of the genus Euphthiracarus was reported from Japan, but two species of the genus were newly found from Oki Island and Miyake Island, respectively. These are both new species and described in the present paper.

Is the Japanese Oribatid Mite Euphthiracarus foveolatus Aoki, 1980 (Acari: Euphthiracaridae) a Junior Synonym of E. cribrarius (Berlese,1904)?

“…; II) Niigata: 1 female, Niigata-shi, Niigata-Pref., 2-XII-1991, from moss cushions growing on city constructions, Dr. J. Aoki leg. This specimen was studied by Aoki, 2000. ; III) Kyoto: 1 female, Asyu Kyoto Pref., 10-XI-1997, Dr. T. Sakata leg.…”

“…Observations were carried out with a compound light microscope on the following specimens (on slides): 1) Holotype (NSMT-Ac 9138) of Euphthiracarus foveolatus Aoki, 1980. There are no paratype specimens or others deposited with the holotype.…”

“…foveolatus, Aoki, 1980;and E. takahasii Aoki, 1980) are currently known from Japan. Euphthiracarus foveolatus was recorded several times from Japan (Fujikawa et al, 1993), but it is a very rare species (Aoki, 2000), and few individuals ware collected at any given time. In the original description (Aoki, 1980), this species was considered to be distinguishable from the Eurasian species E. cribrarius (Berlese, 1904) (not reported from Japan) by two characters: E. foveolatus has "7 pairs of genital setae" and the lengths of aggenital setae ag 1 and ag 2 are equal.…”

“…Euphthiracarus foveolatus was recorded several times from Japan (Fujikawa et al, 1993), but it is a very rare species (Aoki, 2000), and few individuals ware collected at any given time. In the original description (Aoki, 1980), this species was considered to be distinguishable from the Eurasian species E. cribrarius (Berlese, 1904) (not reported from Japan) by two characters: E. foveolatus has "7 pairs of genital setae" and the lengths of aggenital setae ag 1 and ag 2 are equal. However, Aoki (2000) illustrated 9 pairs of genital setae for E. foveolatus, the same number as in E. cribrarius, and explained the text mistake of the number of the genital seta in Japanese.…”

“…In the original description (Aoki, 1980), this species was considered to be distinguishable from the Eurasian species E. cribrarius (Berlese, 1904) (not reported from Japan) by two characters: E. foveolatus has "7 pairs of genital setae" and the lengths of aggenital setae ag 1 and ag 2 are equal. However, Aoki (2000) illustrated 9 pairs of genital setae for E. foveolatus, the same number as in E. cribrarius, and explained the text mistake of the number of the genital seta in Japanese. Also, he illustrated the lengths of ag 1 and ag 2 in his Fig.…”