Radomir Graczyk

External morphology and ontogeny of three species of Damaeidae (Acari: Oribatida)

The morphology of juvenile stages and ontogeny of Belba compta (Kulczynski, 1902), Epidamaeus bituberculatus (Kulczynski, 1902) and Spatiodamaeus verticillipes (Nicolet, 1855) were described and illustrated for the first time. The juveniles of these species have 12 pairs of gastronotal setae (larva has 12 pairs, protonymph loses d-series setae and gains p-series, and 12 pairs remain in this and other nymphs). They differ mainly by the length of setae c 1 and la in the larva, which are relatively long in E. bituberculatus, short in S. verticillipes and of medium size in B. compta. The nymphs of the latter species have long seta c 3, whereas other species have this seta short. In the nymphs of B. compta, adanal setae are smooth; in E. bituberculatus, these setae have long barbs; but in S. verticillipes, they have short barbs. Ontogeny of leg setae is similar in all species, except for famulus (ϵ), which is emergent in the juveniles of B. compta and sunken in other species; the adults of all species have it emergent. Belba compta and E. bituberculatus lose seta c 3 in the adult, and 11 pairs of notogastral setae remain, whereas S. verticillipes loses seta c 3 and one seta of h-series, which is unique in Damaeidae. The diagnoses of B. compta, E. bituberculatus and S. verticillipes are modified and enriched in the morphological characters of juveniles, and systematic values of some morphological characters of juveniles of Belba von Heyden, 1826, Damaeus CL Koch, 1836, Epidamaeus Bulanova-Zachvatkina, 1957, Kunstidamaeus Miko, 2006, Metabelba Grandjean, 1936, Metabelbella Bulanova-Zachvatkina, 1957 and Spatiodamaeus Bulanova-Zachvatkina, 1967 are discussed.

Effects of liquid pig manure fertilization on the density and species structure of Oribatida (Acari) and green forage yield in a lowland meadow in Poland

Effects of liquid pig manure fertilization on the density and species structure of Oribatida (Acari) and green forage yield in a lowland meadow in Poland The effect of liquid pig manure fertilization, with or without the disinfectant VIT-TRA, on oribatid communities was investigated in a lowland meadow in Poland. The disinfectant was tested at 3 concentrations: 0.50% (fungicidal), 0.75% (bactericidal), and 3.00% (viricidal). Liquid pig manure without the disinfectant increased the green forage yield along with increasing doses of this fertilizer, while addition of disinfectants affected the yield in different ways. Low and medium doses of fertilizer (20 and 40 m3·ha-1) with fungicide slightly decreased the yield, while the high dose (60 m3·ha-1) usually increased it, as compared to the control. Low and medium doses of liquid pig manure, treated or not with disinfectants, decreased the abundance of oribatid mites. In contrast, the high dose increased their abundance, except for the plot with a high dose of viricide, where they were slightly less abundant than in the control. In the investigated meadow, Liebstadia humerata, Parachipteria bella and Scheloribates laevigatus were abundant, but reacted negatively to low and medium doses of liquid pig manure treated or not with disinfectants, and positively only to the high dose of fertilizer treated with fungicide and bactericide, as compared to the control plot.

Distribution and population characteristics of the soil mites Diapterobates notatus and Svalbardia paludicola (Acari: Oribatida: Ceratozetidae) in High Arctic Svalbard (Norway)

The Oribatida of High Arctic Svalbard are faunistically relatively well known, but the distribution, density, stage structure and other population parameters of most species are unknown. Here we focus on two ceratozetid species, Diapterobates notatus (Thorell, 1871) and Svalbardia paludicola Thor, 1930, and investigate the summer density, stage and sex structure, proportion of gravid females and the body size of these species in 33 locations and 11 vegetation classes of Svalbard. Diapterobates notatus occurred in all vegetation classes and at 29 locations, whereas S. paludicola occurred in only two vegetation classes and at three locations. The common occurrence of D. notatus in Svalbard may be due to: (1) cosmopolitan nature of this species which inhabits all vegetation classes but with a preference for open Dryas/Carex rupestris communities, (2) high biological potential (females were more abundant than males and carried 6–7 large eggs) resulting in a high proportion of juveniles, and (3) juvenile morphology which possesses long setae that may enhance passive dispersal by the wind. Adult body size was found to be greatest in the floristically diverse Arctic meadows. Svalbardia paludicola was particularly abundant in the Arctic meadow at Reinsdyrflya where juveniles were more plentiful than the adults. The nymphs of this species have shorter gastronotal setae than those of D. notatus which may limit their passive transport by the wind. Scutozetes clavatosensillus Ermilov, Martens & Tolstikov, 2013 was found in Mosselbukta (north Spitsbergen); this is the first observation of this species in Svalbard.

Mites (Acari) at the edges of bog pools in Orawa–Nowy-Targ Basin (S Poland), with particular reference to the Oribatida

Abstract Mites, and among them especially the Oribatida, are very abundant in bogs, being good bioindicators of various changes, but little is known about their reaction to heavy industrial exploitation of bogs. This study aimed to compare the acarofauna of the edges of small pools located in 2 bogs of Orawa-Nowy-Targ Basin (Kotlina Orawsko-Nowotarska), namely Łysa Puścizna (LP) and Bór Podczerwony (BP), degraded to different degrees by peat exploitation. The area of bog LP has decreased since the end of the 19th century by 34%, while that of BP has decreased during this time drastically (by 68%). Water in both studied pools differed from that in natural bogs, reported in the literature, especially in pH, colour, and oxygen conditions (COD and BOD5), and these differences were more pronounced at BP. The abundance of mites was similar to that observed in natural bogs, and the Oribatida dominated among mites, constituting over 99% of them. The species diversity of Oribatida was low in both pools, but especially in pool BP. In both bogs the aquatic species were the most abundant due to the wet study season. The species structure of Oribatida differed, however, from that reported from natural bogs as well as from each other. At the less degraded bog LP the most abundant was Hydrozetes lacustris (D = 69%), while at bog BP, with worse water parameters, Trimalaconothrus maior highly dominated (D = 93%). This suggests that the latter species is very tolerant to water parameters, being a successful coloniser of degraded bogs.

Oribatid mites (Acari: Oribatida) from roofs of houses in Sogn og Fjordane (Norway)

Abstract Oribatid mite communities in moss covering the roofs of buildings in towns of Bolstad, Luster, and Sørheim (in Sogn og F jordane, Norway) were investigated. These mites were rather numerous and rich in species, which was caused mainly by the natural roofing material (rock slates) and the temperate and rather stable maritime climate. In these communities the most abundant were Tectocepheus velatus, Dissorhina ornata, Oppiella uliginosa, Quadroppia quadricarinata, and Oribatula exilis, which are typical soil species. Adults usually dominated in the mite communities, except for Bolstad, where the juveniles were slightly more abundant than the adults. Phauloppia lucorum and Trhypochthonius tectorum were the only species of the group of typical inhabitants of roofs of buildings, but were not numerous in Sogn og Fjordane. In continental climate these species are often abundant on roofs of buildings.

Oribatid mites (Acari, Oribatida) of open and forested habitats of Korčula Island (Croatia)

Abstract Oribatid mites were investigated on Korčula Island (Croatia) in various microhabitats in an open habitat (moss on rock, moss on soil) and in stone pine forest floor (moss, litter, rotting wood) in late August 2004. Special attention was paid to the age structure of species. These mites were rather abundant but their species diversity was low. The highest density was observed in patches of moss in the forest floor, and the lowest density was in rotting wood. Among the oribatid mites, only several species were abundant (Achipteria nitens, Zygoribatula propinqua, Pilogalumna crassiclava, Scheloribates initialis, S. laevigatus, and Tectocepheus velatus). Some species were rich in juveniles, while in others the adults dominated.

Ecology and biology of Hydrozetes paulista (Acari: Oribatida) in the benthic zone of a temporary lake in Brazil

Abstract Oribatid mites are mainly terrestrial animals, but some are aquatic, including all species of the genus Hydrozetes (Hydrozetidae). They have often been recorded in abundance on the waters surface, while their presence in the benthic zone is poorly documented. A litterbag experiment was carried out in Coutos Lake, a shallow temporary lake in Southeast Brazil, in order to study the ecology and biology of Hydrozetes paulista. This mite species greatly dominated the benthic invertebrate community (82%), and at the end of the experiment it reached a density (652 individuals per 1 g of dry substrate) higher than that ever previously reported before for any Hydrozetes species. This density was correlated with some water parameters, stronger with conductivity, and less with temperature. The adults dominated in the stage structure (constituting over 80% of sample population), but the participation of the juveniles increased with the time. Larvae were first noticed on 25th day of experiment and after that were present for the rest of the season. During the course of this experiment, mite fecundity and body size decreased. This species is known as bisexual, but we observed only females in the 5354 adults we collected.

Morphological ontogeny, ecology and some biological parameters of Achipteria magna (Acari: Oribatida: Achipteriidae)

Abstract The morphological ontogeny of Achipteria magna (Sellnick, 1928) is described and illustrated. The adult of this species has many morphological characters of Achipteria Berlese, 1885, such as long and wide lamellae, fused in the medial part, long anterior pteromorphic projections, and 10 pairs of notogastral setae, with longer c2 and la. However, this species has many fine pores on the notogaster and a pair of saccules S1, instead of four pairs of saccules or porose areas that occur in most species of Achipteria. In A. magna, anteroventral apophysis on genua I and II is present, genu IV is longer than tibia IV, seta bv″ on femur II is longer than seta d, seta v″ on this segment is more than twice longer than seta bv″, seta l′ on femur III is short and leg claws are smooth. The juveniles of this species are stocky, with the prodorsal setae minute or short and smooth. The gastronotal setae of the larva are short or of medium size, thick and barbed, except for minute c2, c3 and h3. In the nymphs, all setae are thick and barbed, but c2 and c3 are shorter than c1, and p2 and p3 are shorter than p1. The morphological ontogeny of A. magna is compared with some congeners, and Pseudachipteria Travé, 1960 and Campachipteria Aoki, 1995 are considered junior synonyms of Achipteria. The ecology and some biological parameters of A. magna are also investigated.

Morphological ontogeny, distribution and ecology of Edwardzetes edwardsii and Sphaerozetes orbicularis (Acari: Oribatida: Ceratozetidae)

Abstract In this study the morphological ontogeny, distribution and ecology of Edwardzetes edwardsii (Nicolet, 1855) and Sphaerozetes orbicularis (C.L. Koch, 1835) were investigated. The latter species looks strikingly similar to S. piriformis (Nicolet, 1855), and was recognized by a rounded distal part of lamellar cusp, which in S. orbicularis had an outer spine. However, the shape of the lamellar cusp varies in Norwegian adults of S. orbicularis being rounded or with one or two spines, which puts in question the validity of S. piriformis. Our study on the morphology of juveniles of these two morphological forms of S. orbicularis also indicates that they are identical, so we provisionally consider S. piriformis as a junior synonym of S. orbicularis (syn. nov.). The juveniles of E. edwardsii and S. orbicularis have a humeral organ and a humeral macrosclerite, which is common in Sphaerozetinae, and carry seta c1 on the humeral macrosclerite. In the juveniles of E. edwardsii most gastronotal setae are of medium size and blunt, but the gastronotal shield of the larva is divided in two parts, whereas in the nymphs this shield is uniform. In all juvenile stages of S. orbicularis the gastronotal setae are short and the gastronotal shield is uniform. The adult of E. edwardsii has a rounded rostrum and 10 pairs of long notogastral setae, including c2, whereas that of S. orbicularis has rostrum with two deep incisions and 11 pairs of short notogastral setae, including c2 and c3, which is typical of Sphaerozetes Berlese, 1885, but unique in Sphaerozetinae. Edwardzetes edwardsii has a holarctic distribution, whereas S. orbicularis is a Palaearctic species. The former species prefers forest litter, whereas the latter species prefers moss.

Preliminary study of the impact of pig or goat manure fertilization of a meadow on oribatid mites

Abstract We investigated the impact of pig or goat manure fertilization of a meadow with doses of 80 kg N ha−1, 140 kg N ha−1, and 200 kg N ha−1 (plots 1-6) on oribatid mites. A control plot (0) was left unfertilized. The manure was applied to the meadow in the early spring of 2012, and soil samples were collected in the spring of 2012 and 2013. In total, 6053 oribatid mites were examined, including 1163 juveniles. The effect of fertilizing on the Oribatida depended on the dose of manure, but not on its type. A low dose of pig or goat manure did not affect the density of Oribatida, whereas the other doses decreased it, but only the highest doses decreased it significantly, compared to the control. Species diversity decreased with the dose of manure. In total, 24 species of Oribatida were found and some species reacted differently to both types of manure. For example, a low dose of pig manure significantly increased the density of Eupelops occultus, whereas the density of other species significantly decreased under the influence of the highest dose of pig manure (Achipteria coleoptrata), highest doses of pig and goat manure (Galumna obvia, Liebstadia similis), and medium and highest doses of goat manure (Scheloribates laevigatus).