Comparative morphological and biometrical studies on Trhypochthonius species of the tectorum species group (Acari: Oribatida: Trhypochthoniidae)

.............................................................................................................................................................................. 2 Introduction ......................................................................................................................................................................... 2 Methods ............................................................................................................................................................................... 3 1. Redescriptions and descriptions of species ..................................................................................................................... 4 Diagnosis of the genus Trhypochthonius and the tectorum-complex .......................................................................... 4 Diagnosis of adult Trhypochthonius ........................................................................................................................... 4 The tectorum-species-group ........................................................................................................................................ 4 Trhypochthonius tectorum (Berlese, 1896) .................................................................................................................. 5 Redescription of Trhypochthonius americanus (Ewing, 1908) ................................................................................... 8 Redescription of Trhypochthonius silvestris Jacot, 1937 ............................................................................................ 9 Description of Trhypochthonius silvestris europaeus n. subsp. ................................................................................. 12 Trhypochthonius japonicus Aoki, 1970 ..................................................................................................................... 16 Trhypochthonius japonicus n. forma occidentalis ..................................................................................................... 16 2. Biometrical analyses ..................................................................................................................................................... 19 Statistical methods ..................................................................................................................................................... 19 Comparison of Trhypochthonius tectorum populations ............................................................................................. 20 Comparison of Trhypochthonius species ................................................................................................................... 20 Cluster analyses on the interrelation of the Trhypochthonius species ....................................................................... 23 3. Phylogenetical relationships and biogeography of the species ..................................................................................... 26 Key to adults of the Central European Trhypochthonius species .............................................................................. 28 Acknowledgements ........................................................................................................................................................... 29 References .......................................................................................................................................................................... 29