Trhypochthonius japonicus Aoki, 1970

Weigmann, Gerd & Raspotnig, Günther, 2009, Comparative morphological and biometrical studies on Trhypochthonius species of the tectorum species group (Acari: Oribatida: Trhypochthoniidae), Zootaxa 2269 (1), pp. 1-31 : 16

Trhypochthonius japonicus Aoki, 1970

Within our studies on Trhypochthonius tectorum in Austria some other specimens could not be assigned to T. tectorum or to T. s. europaeus, as they had different chemical characteristics of the opisthonotal gland secretions and different morphological and molecular-genetic characters. European specimens like these were possibly misinterpreted as “ T. tectorum ” in the past. These European populations are highly similar to Trhypochthonius japonicus Aoki, 1970 , from Japan, and we consider them conspecific. The existence of some small but constant differences cause us to regard the European populations as a regional variant (forma B), here named Trhypochthonius japonicus forma occidentalis. Table 3 presents some morphometric data of the Austrian population from Carinthia in comparison with the nominal form from Japan (recalculated after indications of Aoki 1970). In the following, firstly the species diagnosis is given after the Japanese data; then we present the characteristics of Trhypochthonius japonicus forma occidentalis from Europe with remarks on the differences.

Trhypochthonius japonicus Aoki, 1970: 404

Trhypochthonius japonicus Aoki, 1970 : Balogh & Mahunka (1983: 196, Fig. 118F–J)

Diagnosis. Body length about 640-690 µm. Most notogastral setae bacilliform with spinose setulae, never distally broadened; setae c 1 and c 2 (range 11-24 µm) half or less the length of c 3 and d 3 (40-53 µm), d 1 and smaller d 2 (13-16 µm), e 1 of medium length (35-40 µm); posterior notogastral setae longer, p 1 the longest (90- 93 µm), spinose and acuminate; p 2 remarkably long (80-81 µm), acuminate and sparsely spinose; h 3 and p 3 smooth setiform, less than half the length of p 2. 6-10 pairs of genital setae, mostly 8. (cf. table 3). Notogaster with distinct posterior boss.