The first report on the oribatid mites (Acari: Oribatida) in tundra of the Chunatundra Mountains on the Kola Peninsula, Russia

The aim of this research was to obtain initial data on the fauna and abundance of the oribatid mites from the main types of the mountain tundra habitats of the Chunatundra Mountains. Four plots, including two lichen tundra plots, one dwarf shrub tundra plot and one sphagnum bog in the belt of mountain tundra were investigated. Multidimensional scaling and discriminant function analysis were used to identify trends in the fauna and abundance of oribatid species through the explored plots. A total of 70 species and one subspecies from 37 genera and 24 families were found during the course of this investigation. Nine species, one subspecies, one genus and one family of oribatid mites have been added to the fauna of the Kola Peninsula. The families Brachychthoniidae, Oppiidae and Suctobelbidae are the most diverse in the discovered local fauna. According to literature data, the first two families are characteristic of the low tundra communities, the third family is more common for the boreal zone. The discovered oribatid fauna is similar to the fauna of other tundra sites of the Kola Peninsula studied previously and is significantly different to the local oribatid mite faunae of the Scandinavian Peninsula. The abundance of the adult oribatid mites reached 39 080 ind./m2 in the lichen tundra and 56 200 ind./m2 in the dwarf shrub tundra. The minimum abundance of oribatid mites, 18 640 ind./m2 was found in the sphagnum bog. Differences in the oribatid mite complexes of lichen tundra, dwarf shrub tundra and the sphagnum bog were found. The species Carabodes labyrinthicus, Nothrus borussicus, Sellnickochthonius immaculatus, Mycobates sarekensis, and Tectocepheus velatus were associated with the lichen tundra habitats. Nanhermannia sellnicki, Chamobates borealis and a few species of Oppiella and Suctobelbella were associated with the dwarf shrub tundra. Mucronothrus nasalis, Limnozetes ciliatus, Platynothrus peltifer, Trimalaconothrus foveolatus, Limnozetes cf. rugosus, and Trimalaconothrus maior are most characteristic of the sphagnum bog. The family Suctobelbidae was represented by a large number of species, while the families Ceratozetidae and Camisiidae were much less diverse. The low diversity of Ceratozetidae, a high diversity of Suctobelbidae and relatively high abundance of oribatid mites in the explored tundra habitats may be explained by an ambivalent nature of the oribatid community, which combines boreal and arctic features due to marine climate. Also, this result may be a feature of a local mountain tundra which is surrounded by the underlying belts of the mountain forests that are a source of the increasingly diversity of species.

Seasonal dynamics of mites (Acari) in pastures and meadows in Poland, with species analysis of Oribatida

The study involved three pastures, grazed by geese, goats and fallow deer, and three nearby meadows (control plots) situated in north-central Poland. Samples of 150 cm3 each (6 cm of soil and 3 cm of lower parts of plants) were collected in spring, summer and autumn 2016 and 2017 in 10 replications, 360 samples in total. This material included 22.561 mites, among which Oribatida accounted for 69%, Mesostigmata for 21%, and other mites for 10%. At most study sites, both pastures and meadows, no significant seasonal differences in the abundance of Oribatida and Mesostigmata were seen. Such differences were only observed for the third category of other mites that were the most abundant in spring and usually the least abundant in autumn. Also species diversity of Oribatida differed between the seasons – in all pastures it was the highest in summer and the lowest in spring, while in all meadows it was the highest in spring and decreased towards autumn. Oribatid species were more affected by the habitats than by seasons, as some species were strongly associated with pastures (Platynothrus peltifer), other with meadows (Achipteria coleoptrata, Liebstadia similis, Metabelba pulverosa, Scheloribates laevigatus and Sellnickochthonius immaculatus), and some (Eupelops occultus and Tectocepheus velatus) were abundant in both habitats. Although the effect of seasonality was weaker than that of the habitat, it was still perceptible. Platynothrus peltifer was most associated with autumn, T. velatus with spring, E. occultus with spring and summer and L. similis with summer.

Oribatid mites (Acari: Oribatida) of hygrophyte grasslands on Transcarpathian Lowland

Fauna and ecological diversity of oribatid mites of hygrophyte grasslands on Transcarpathian lowland is considered in the paper. For Transcarpathia, such studies have not been conducted before. For hygrophyte grasslands 45 species of Oribatida (25 families, 34 families) are registered. The most numerous among detected taxa were Platynothrus peltifer, Ceratozetes mediocris and Oppiella nova. It has been established that dominant role belongs to the surface-soil morpho-ecological group of oribatid mites. In the ecological structure, predominant role is inherent of hydrophilous and eurytopic species.