Oribatid Research Articles

New arboreal mite species of Oribatulidae and Oripodidae (Acari, Oribatida, Oripodoidea) from Vietnam

ABSTRACT Two new oribatid mite species—Phauloppia dilatata sp. nov. (Oribatulidae) and Pirnodus partiarus sp. nov. (Oripodidae)—are described, based on adults collected from tree branches of Haldina cordifolia in southern Vietnam. The genus Pirnodus is recorded for the first time in the Oriental region. The generic diagnoses for Phauloppia and Pirnodus are revised. The identification keys to the Oriental representatives of Phauloppia and the known representatives of Pirnodus are provided. Pseudopirnodus madegassus is transferred to Pirnodus; the initial placement of Pirnodus domrowi in Pirnodus is confirmed. http://zoobank.org/urn:lsid:zoobank.org:pub:298B44CE-C965-4B10-8B0F-A3CDB9BAFD57

Contribution to the knowledge of the oribatid mite genus Arthrovertex (Acari, Oribatida, Scutoverticidae), with description of a new arboreal species from Vietnam

ABSTRACT A new arboreal species of Arthrovertex (Oribatida, Scutoverticidae)—A. kornilovi sp. nov.—is described, based on adults collected from tree branches of Dipterocarpus alatus in Cat Tien National Park, Vietnam. A generic diagnosis, identification key, distribution, and habitats of representatives of Arthrovertex are presented. http://zoobank.org/urn:lsid:zoobank.org:pub:15169867-0FAB-43D6-94F4-9D3B4F4A9F47

Ontogenetic instars of Zygoribatula excavata, with remarks on juveniles of Oripodoidea (Acari: Oribatida)

Information on the morphological ontogeny of oribatid mites of the family Oribatulidae is very scarce, and the juveniles of most species are unknown yet. In this work, the ontogenetic instars of the semicosmopolitan species, Zygoribatula excavata Berlese, 1916 are studied. The juvenile instars of this species are morphologically similar to those of the other species of Zygoribatula, and this genus can be included among those in which species are difficult to distinguish based on juvenile characteristics alone. As information on the morphological ontogeny of most species of Oribatulidae is still insufficient or unknown, a comparison on the juvenile characteristics of the families belonging to the superfamily Oripodoidea is given based on our own data and available literature sources. The major characteristics of juvenile instars of 10 families and 21 genera are presented. There are few characters, such as body shape and size, pattern of cuticle, excentrosclerites at gastronotic setae, size and morphology of setiform organs, such as bothridial as well as gastronotic setae that distinguish the families or genera of Oripodoidea.

First data on ontogeny of the oribatid mite family Caloppiidae (Acari, Oribatida), with description of juvenile instars of the representative of the genus Zetorchella.

Juvenile instars of Zetorchella arsiensis (Oribatida, Caloppiidae) are described, based on specimens collected from mosses on the swamp at the top of the mountain in Arsi Mountains National Park, Ethiopia. It is the first data on ontogeny for the family Caloppiidae. Main morphological differences between juveniles of Caloppiidae with other families in Oripodoidea are presented.

<i>Makaroviella exigua</i> (Acari, Oribatida, Licnobelbidae), a new genus and species from Cuba

A new oribatid mite genus collected from Cuba – Makaroviella gen. n. (Oribatida, Licnobelbidae), with Makaroviella exigua sp. n. as type species – is proposed and described. It can be distinguished from both known licnobelbid genera (Flabellobelba and Licnobelba) mostly by: the number and the localization of notogastral setae, the localization of rostral setae and adanal setae ad1, and the absence of lateral enantiophyses. An identification key to the known species of Licnobelbidae is provided.

After chemo-metamorphosis: p-menthane monoterpenoids characterize the oil gland secretion of adults of the oribatid mite, Nothrus palustris

The oil gland secretion of the oribatid mite Nothrus palustris is known to show the phenomenon of juvenile–adult polymorphism, i.e., juvenile instars produce secretions predominated by geranial, whereas adults secrete dehydrocineole along with a number of chemically unidentified compounds. We here re-analyzed the secretions of adult N. palustris by GC–MS and NMR spectroscopy, eventually identifying the unknown compounds as p-menthane monoterpenoids. The major components were two isomeric 6-isopropenyl-3-methyl-cyclohex-3-en-1-yl formates (= p-1,8-menthadien-5-yl formates), which accounted for about 75% of the secretion. These were accompanied by five additional, only partly identified p-menthanes (or p-methane-derivatives), all of which represented minor or trace components. In addition, adult secretions contained two C21-hydrocarbons, 1,12-heneicosadiene (major) and a heneicosatriene (minor). Menthane monoterpenoids represent a novel sub-class of terpene compounds in the oil gland secretions of Oribatida. In case of N. palustris, we assume that both geranial and p-menthane monoterpenoids arise via the mevalonate pathway which obviously shows a split at the level of geranyl pyrophosphate, leading to geranial in juveniles and to p-menthanes in adults. The significance of methane occurrence in oil glands as well as the taxonomic distribution of juvenile–adult polymorphism in oribatid oil gland secretions is discussed. The latter phenomenon—i.e., “chemo-metamorphosis” of secretions—is not known from early- and middle-derivative Oribatida nor from Astigmata, but appears to be more common in some derivative desmonomatan and brachypyline oribatid groups.

First checklist of the oribatid mites (Arachnida: Oribatida) of the Gran Chaco region (South America) with new records

The South American Gran Chaco ecoregion extends through great areas of Argentina, Paraguay, Bolivia, and Brazil. The region includes vast forests that serve as an important reservoir of tropical and subtropical diversity. In spite of its extent and high biodiversity, it remains an unexplored area regarding Oribatida. We made bibliographic research about the oribatid mites previously registered. In the bibliography of Argentina and Paraguay, a total of 53 species are cited for this region. From our own works in the Argentinean provinces of Santiago del Estero and Chaco, we add some new records of Oribatida in the area. We provide a list of the species registered to date, including 48 firstly recorded in this work, as well as new localities for other 11 species previously known for the area. This paper almost doubles the number of registered species for this highly diverse but poorly known ecoregion, adding information towards the true diversity of Oribatida in the Chaco region.

Ecomorphological groups in oribatid mite communities shift with time after topsoil removal – Insight from multi-trait approaches during succession in restored heathlands

Restoration of nutrient-enriched heathlands and similar dry habitats via topsoil removal requires the re-assembly of above and belowground communities to attain fully functional ecosystems. Top-soil removal provides unique opportunities to study the assembly processes, but research has traditionally focused on succession of the aboveground part of the ecosystem. Oribatid mites are a dominant group of soil mesofauna in the belowground part of heathlands. They possess attributes for bioindication and have shown high sensitivity to environmental changes during succession. However, few studies have focused on changes in functional community profiles and the factors shaping them with time. We sampled heathlands of different restoration ages located in East Belgium, studied traits of oribatid mite communities of a chronosequence, and assessed the interaction between traits and abiotic variables using community weighted means (CWM) and an iterative co-correlation analysis between abiotic parameters, species trait attributes and species abundances (iterative RLQ analysis). Our study suggests that moisture preferences, concealability (i.e. defence mechanism against desiccation and predation), and body length were the dominant traits structuring the oribatid mite communities. We found that both dispersal and environmental filters shape the assembly of oribatid mite communities, but these drivers dominate different stages of succession. Moreover, trait assemblages deriving from three well-defined eco-morphological groups closely followed these constraints in time. Thus, the shifting dominance of specific groups provides valuable insight on the soil community functioning in a changing environment.

Contribution to the knowledge of the oribatid mite genus Gymnobodes (Acari, Oribatida, Carabodidae), with description of a new species from Mexico

A new species of Gymnobodes (Oribatida, Carabodidae) – G. paraminimus sp. n. – is described from leaf litter of secondary semi-evergreen tropical forest in Mexico. A revised generic diagnosis, identification key and data on distribution and habitats of representatives of the genus are presented.

New faunistic and taxonomic data on oribatid mites (Acari: Oribatida) of Thailand

This study is based on oribatid mite materials collected from the vicinities of Phatthaya city and the Samet Island in Thailand; 18 species from 14 genera and 11 families are registered, of these, nine species are recorded from the Thai fauna for the first time. A new species of the genus Dolicheremaeus (Otocepheidae) – D. phatthayaensis sp. n. – is described. The supplementary description of Galumna paracalcicola Ermilov et Anichkin, 2014 is presented based on specimens from Thailand. Identification keys to the known representatives of the genera Dolicheremaeus from Thailand and Galumna from the Oriental region are presented. Galumna indica Hafeez Kardar, 1989 and G. striata Hafeez Kardar, 1989 are combined in the genus Setogalumna.

Contribution to the knowledge of the oribatid mite genus Discoppia (Acari, Oribatida, Oppiidae)

The supplementary description of the oribatid mite species Discoppia (Cylindroppia) cylindrica (Pérez-Íñigo, 1965) (Oribatida, Oppiidae) is presented, based on materials collected from deep layers of coastal sandy soils in the Republic of Dagestan, eastern Caucasus. The morphology of exobothridial seta, gnathosoma and ovipositor, and the identification of leg setae and solenidia are given for the first time for this species. The revised generic diagnosis, identification key, distribution, and habitats of all known representatives of Discoppia Balogh, 1983 are presented. Some taxonomic nuances within Discoppia are discussed, resulting in the following proposals: Oppia bifidus Bayoumi and Al-Khalifa, 1985 is a junior synonym of D. (C.) cylindrica; Oppia agricola Fujikawa, 1982 is not synonym of D. (C.) cylindrica and transferred to the genus Microppia Balogh, 1983; Oppia tenuis Hammer, 1958 is not representative of Discoppia; Discoppia (Cylindroppia) rostroincisa Subías and Rodríguez, 1986 n. stat. (instead of the existing subspecies status). Together with D. (C.) cylindrica, in the same samples, two rare Oppiidae species were found: Oxyoppia (Oxyoppiella) minuscula Hugo-Coetzee, Lotfollahi, Abbasi-Kalo and Movahedzade, 1917 (known only from the open habitats in Iran) is first recorded in Russia; Graptoppia (Stenoppia) boucheri Ermilov and Frolov, 2021 (known from passalid beetles collected in Ghana and Gabon, West Africa) is first found in the Palaearctic. Both findings in Dagestan are among the northernmost records of their semicosmopolitan subgenera.

Faunistic and taxonomic additions to the oribatid mites (Acari, Oribatida) of Cuba

The present study is based on oribatid mite materials collected from leaf litter in two forest locations in Cuba. A list of 64 species, belonging to 47 genera and 31 families, is presented. Of these, one genus and two species are recorded for the first time from the Neotropical region; 17 species, one subgenus, six genera, and two families are recorded for the first time from Cuba. Two new species of the superfamily Oripodoidea—Lagenobates fossatus Ermilov and Kontschán n. sp. (Haplozetidae) and Muliercula curvilineata Ermilov and Kontschán n. sp. (Scheloribatidae)—are described.

New species of oribatid mites (Acari, Oribatida) with auriculate pteromorphs from Indonesia

The oribatid mite genera Carinogalumna (Galumnidae) and Neoribates (Parakalummidae) are recorded for the first time in Indonesia. Two new species—Carinogalumna widyastutiae sp. nov. and Neoribates (Neoribates) klarneri sp. nov.—are described from soil and litter in rubber and oil palm plantation systems on the island of Sumatra. An identification key to the 28 known species of Neoribates from the Oriental region is provided.

Oribatid mites in different Mediterranean crop rotations fertilized with animal droppings.

Unsustainable soil management is one of the drivers of soil degradation, but impact assessment requires the development of indicators. Oribatids might be considered as early indicators of disturbances due to the stability of their community. The aim of this study was to investigate the feasibility of oribatids as bioindicators of sustainable agricultural practices. Under a dry Mediterranean climate, three fertilization experiments - two under a two-crop rotation system and one under maize monoculture and established 12 years earlier - were sampled 3× for oribatid identification during the last annual cropping cycle. The hypothesis was that different nutrient and crop managements affect the number of oribatid species and individuals present, and these parameters could be used as indicators of soil degradation. In total, 18 oribatid species were identified, and 1974 adult individuals were recovered. Maximum abundance was found prior to sowing. Pig slurry (PS) vs. control, and dairy cattle manure (CM) vs. mineral fertilization increased oribatid abundance. This increase was evident when the average applied rates with PS were ca. 2 Mg of organic matter (OM) ha- 1 yr- 1, or higher than ca. 4 Mg OM ha- 1 yr- 1 for CM. When the preceding crop was wheat and PS or CM were used, Oribatula (Zygoribatula) excavata (which reproduces sexually) predominated. In maize monoculture fertilized with CM, Tectocepheus sarekensis and Acrotritia ardua americana (which can reproduce through parthenogenesis) prevailed vs. Oribatula, which indicated a heavily disturbed soil. Under this specific Mediterranean environment, the predominance of certain parthenogenic oribatid species and the number of individuals provide advanced warning on soil degradation.

Oribatid Mites (Oribatida) Associated with Nests of Hollow-Nesting Birds, on the Example of a Model Species, the European Pied Flycatcher (Ficedula hypoleuca), in the Taiga Forests of the European North-East of Russia

The authors have obtained original material on the fauna and population structure of oribatid mites inhabiting nests of the European Pied Flycatcher (Ficedula hypoleuca, Passeriformes, hollow-nesting bird) on the territory of the taiga zone of the European North-East of Russia. Long-term research and the collection of nests were carried out in the green zone of Syktyvkar in 2017–2022. Observations were made for artificial nests (hollows) of a box type with a bottom area of 100 cm2. The material of the tray was collected completely. In 135 studied nests of Pied Flycatchers, 1762 specimens were found and identified for 22 species of oribatid mites from 19 genera and 16 families. In the nests of the Pied Flycatcher, a complex of species was found that is known as an arboricolous species for this region; these are Oribatula (Zygoribatula) propinqua, Oribatula (Z.) exilis, Trichoribates (T.) berlesei, and Ameronothrus oblongus. We suggested that arboricolous species, as well as eurytopic species, can actively inhabit bird nests. Highly numerous in our collections were representatives of the Oribatulidae and Scheloribatidae families; they are Oribatula (Z.) propinqua, Oribatula (Z.) exilis, Oribatula (O.) tibialis, and Scheloribates laevigatus. Epigeic species are dominated by the species number. The fauna of oribatid mites mainly included widespread Holarctic species (54.54%).

Community structure of soil mites under different crops and its response to environmental factors in the buffer zone of Shibing Karst World Natural Heritage

To reveal the differences in the community structure of soil mites under different crop environments in the buffer zone of the Shibing Karst World Natural Heritage Site, soil mites from corn fields (CF), pear tree lands (PL), tobacco fields (TF), grape fields (GF), and plum gardens (PG) were collected in the buffer zone in January 2022. Through the identification of mite specimens and data analysis, differences in the number of families, genera, individuals, individual density, diversity, similarity of communities, ecological groups of oribatid mites, and responses to environmental factors of soil mites under different crop environments were determined. The results showed that: (1) A total of 6941 soil mites were captured in the study area, belonging to 130 genera, 75 families, and 3 orders. The number of soil mite genera (CF and TF > PL > PG > GF) and number of soil mite individuals (PG > PL > GF > TF > CF) showed characteristics of differential distribution and surface soil aggregation in the five habitats. (2) Scheloribates, Protorobotritia, and Tectocepheus were the dominant genera in the study area. Lohmannia, Scheloribates, and Tectocepheus, representative species that indicate a good soil environment, were distributed in the sample plots of CF, PL, and PG to varying degrees, indicating that the ecological environment of these three crops was healthy. (3) The diversity index of PG was the highest, and similarity analysis of the five habitats revealed that they were at a medium level of similarity. (4) The ecological groups of oribatid mites in the different crop environments were dominated by the overall (O) type, which is a combination of Macropylina, Gymnonota, and Poronota. (5) The community structure of soil mites was sensitive to bulk density (BD), natural water content (NWC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available potassium (AK), and soil organic matter (SOM). Based on the above results, there were differences in the community structures of soil mites under different crop environments in the study area. The identification of the dominant mite genera can preliminarily indicate the environmental conditions of different crops, and a special correlation exists between the community structure of mites and environmental factors. Studying the community structure of mites in different crop environments in the Shibing Karst World Natural Heritage Site buffer zone is important in ensuring the ecological protection and sustainable development of the buffer zone. Furthermore, the results of this study support the role of the buffer zone as an ecological protection barrier for the heritage site.

First record of the genus Parapyroppia Pérez-Íñigo & Subías, 1979 (Acari, Oribatida, Ceratoppiidae) from China, with description of a new species

The oribatid mite genus Parapyroppia Pérez-Íñigo & Subías, 1979 (Ceratoppiidae) is reported in China for the first time. During investigation of soil biodiversity in northeast China in 2021, a new species, Parapyroppia changbaiensis sp. nov., was found from soil and litter of north slope of Changbai Mountain in Erdaobaihe Town, Jilin Province. The main purpose of study is to describe and illustrate this new species. In addition, an updated generic diagnosis, a checklist and a key to world species of Parapyroppia are presented.

One step closer but still far from solving the puzzle – The phylogeny of marine associated mites (Acari, Oribatida, Ameronothroidea) inferred from morphological and molecular genetic data

Abstract Marine associated oribatid mites belong mainly to the Ameronothroidea which represent a very small percentage of all Oribatida. Over the last decades the systematics and evolutionary history of this group has been discussed controversially and still there is no consensus concerning several issues. The extreme marine environment may have resulted in parallel morphologies complicating the classification and estimation of phylogeny based on discrete morphological traits. In the present study, we performed a molecular genetic study using a mitochondrial and two nuclear markers to infer the phylogeny of this group. Additionally, we reconstructed the phylogeny of Ameronothroidea based on morphological data using different algorithms. Both methods resulted in largely congruent topologies and highlight the following important points: the Ameronothroidea represent a paraphyletic assemblage; the Podacaridae are a distinct family and should be excluded from Ameronothridae; the Fortuyniidae, Selenoribatidae and Tegeocranellidae constitute a monophyletic lineage; and certain genera of Selenoribatidae need a revision. These results demonstrate that the classification of Ameronothroidea and certain positions within this group need to be thoroughly reconsidered and revised. The present study also shows that phylogenetic estimates based on coded morphological data can be a very helpful tool for verifying and supporting molecular phylogenies.

Wolbachia springs eternal: symbiosis in Collembola is associated with host ecology.

Wolbachia are endosymbiotic alpha-proteobacteria infecting a wide range of arthropods and nematode hosts with diverse interactions, from reproductive parasites to obligate mutualists. Their taxonomy is defined by lineages called supergroups (labelled by letters of the alphabet), while their evolutionary history is complex, with multiple horizontal transfers and secondary losses. One of the least recently derived, supergroup E, infects springtails (Collembola), widely distributed hexapods, with sexual and/or parthenogenetic populations depending on species. To better characterize the diversity of Wolbachia infecting springtails, the presence of Wolbachia was screened in 58 species. Eleven (20%) species were found to be positive, with three Wolbachia genotypes identified for the first time in supergroup A. The novel genotypes infect springtails ecologically and biologically different from those infected by supergroup E. To root the Wolbachia phylogeny, rather than distant other Rickettsiales, supergroup L infecting plant-parasitic nematodes was used here. We hypothesize that the ancestor of Wolbachia was consumed by soil-dwelling nematodes, and was transferred horizontally via plants into aphids, which then infected edaphic arthropods (e.g. springtails and oribatid mites) before expanding into most clades of terrestrial arthropods and filarial nematodes.

Two new species of <i>Anderemaeus</i> (Acari, Oribatida, Anderemaeidae) from Peru

The oribatid mite genus Anderemaeus (Oribatida, Anderemaeidae) is recorded from Peru for the first time. Two new species of this genus, A. friedrichi sp. n. and A. paracapitatus sp. n., are described based on material collected from soil and litter in Andean mountain forests.