Catalogue of juvenile instars of oribatid mites (Acari: Oribatida)the next decade (20142023).

In its traditional, paraphyletic context (sans Astigmata), oribatid mites comprise more than 11,000 known species (Subas 2022). They are largely fungivores and decomposers in organic horizons of soil and have a plesiotypic ontogeny that includes four active, free-living juvenile instars. In a taxonomically organized 2014 catalogue, we summarized literature resources concerning the 805 species for which ontogenetic data (mainly morphological) were available. Herein, we supplement that catalogue with all data known to us that were published during the intervening decade. These relate to 267 species, of which 165 were described prior to 2014. As in the 2014 catalogue, representation is strongest among: the middle-derivative hyporder Nothrina; brachypyline superfamilies that are affiliated with aquatic, semiaquatic or intertidal environments (Limnozetoidea, Ameronothroidea); some eupheredermous groups (Plateremaeoidea, Damaeoidea); and Ceratozetoidea. Also as in 2014, groups that are underreprented, based on their high known diversity, are the ptyctimous Mixonomata (Euphthiracaroidea, Phthiracaroidea) and the brachypyline superfamilies Oppioidea and Oripodoidea.

Remarks on the genus Phymatodiscus Berlese, 1917, with the description of Phymatodiscidae fam. nov. and Bardizoneotvosi gen. nov., sp. nov. from Indonesia (Acari, Mesostigmata).

Phymatodiscidaefam. nov. is diagnosed, with Phymatodiscus as the type genus. A new genus, Bardizongen. nov., with Bardizoneotvosisp. nov. (from Indonesia) as the type species, is erected to accommodate the Phymatodiscus species with an eye-like dorsal depression. Six Phymatodiscus species are reclassified as Bardizon: B.aokii (Hiramatsu, 1985), comb. nov., B.haradai (Hiramatsu, 1985), comb. nov., B.oculatus (Hirschmann, 1977), comb. nov., B.kuni (Kontschán & Starý, 2011), comb. nov., B.insolitus (Kontschán & Ripka, 2016), comb. nov., and B.malayicus (Kontschán & Starý, 2012), comb. nov. The new species differs from the previously described congeners in the sculptural pattern, the shapes of the dorsal and ventral setae, and the sculptural pattern of the sternal shield of the male and the genital shield of the female. A list of all known phymatodiscid species is presented. Phymatodiscustitanicus (Berlese, 1905) is moved to the genus Bostocktrachys: B.titanicus (Berlese, 1905), comb. nov. (family Trachyuropodidae).

Taxonomic contribution to the knowledge of Galumnidae (Acari, Oribatida, Galumnidae) from Cuba.

The present study is based on galumnid mites (Oribatida, Galumnidae) collected from leaf litter of two mixed forests in Cuba; six species from three genera are identified. Three new species-Pergalumna (Pergalumna) cienfuegosensis sp. nov., P. (P.) foveolatostriata sp. nov. and Galumna (G.) gigantea sp. nov.-are described. Allogalumna brevisetosa (Bayartogtokh & Weigmann, 2005) is recorded in the Neotropical region for the first time; P. (P.) obvia (Berlese, 1914) is recorded in Cuba for the first time.

Two new species of Cunaxa (Acari, Prostigmata, Cunaxidae) from South-East Asia with a world key to the genus.

Two new mite species of the family Cunaxidae (Acari, Prostigmata)-Cunaxa asiatica sp. nov. and C. smileyi sp. nov.-are described from Vietnam, based on females. Cunaxa asiatica sp. nov. is similar to C. doxa (Chaudri, 1980) in having the medial hysterosomal shield smooth and bearing setae c1-e1, c2, but differs from the latter by the presence of 1 sts, finger-like palpofemoral apophysis and smooth setae c1-e1 on basifemora IV (vs. 2 sts, uncinate palpofemoral apophysis and spiculate c1-e1 in C. doxa). Cunaxa smiley sp. nov. is similar to C. oblongostriata Kalúz and Ermilov, 2022 in having 4-4-4-4 sts on telofemora I-IV and 2 solenidia on genu II, but differs from the latter by the presence of 3-3-3-0 sts on basifemora I-IV, 1 asl and 5 sts on genu IV, and well developed medial hysterosomal shield (vs. basifemora I-IV setal formula of 3-3-3-1 sts, genu IV bearing 7 sts, and the hysterosomal medial shield absent in C. oblongostriata).

Contribution to the knowledge of the Neotropical Uropodina (Acari: Mesostigmata).

Two new species of Uropodina are described from PeruStammeroplitis panguanaensis sp. nov. and Rotundabaloghia (Circobaloghia) koepckeorum sp. nov.. The genus Stammeroplitis is diagnosed and a key to its Neotropical species is presented. Twenty species of Oplitis are moved to Stammeroplitis. The new family Clausiadinychidae fam. nov. is established for the genus Clausiadinychus and a key to the known species of Clausiadinychus species is provided. New information is presented for three known species of Uropodina (Clausiadinychus quadricaudatus Hirschmann, 1973, Rotundabaloghia dillerae Boszyk, 2019 and Trichouropoda solaris Hirschmann, 1972).

Three new species of Oppiidae (Acari, Oribatida) from Mexico.

Three new species of Oppiidae (Oribatida)Graptoppia (Apograptoppia) rooensis sp. nov., Neoamerioppia (Neoamerioppia) mexicoensis sp. nov., and Ramusella (Insculptoppia) quintanaensis sp. nov.are described based on adults collected from leaf litter in a large karst pit in the secondary semi-evergreen tropical forest in Mexico. The subgenus Graptoppia (Apograptoppia) is recorded for the first time in the Neotropical region.

Contribution to knowledge of the oribatid mite genus Symbioribates (Acari, Oribatida, Symbioribatidae), with descriptions of two new arboreal species from Vietnam.

The family Symbioribatidae is recorded in Vietnam for the first time. Two new arboreal species of SymbioribatesS. bimorphus sp. nov. and S. tripartitus sp. nov.are described, based on adults (males and females) collected from tree branches of Dipterocarpus alatus in Cat Tien National Park, Vietnam; the former species is sexually dimorphic, the latter species is the first non-sexually dimorphic representative within the genus. The generic diagnosis is presented. An identification key, distribution and habitats to the known representatives of Symbioribates are provided.

Ontogenetic instars of the oribatid mite Spatiodamaeus kalugaensis sp. nov. (Acari, Oribatida, Damaeidae) from Russia.

A new species of the genus Spatiodamaeus (Oribatida, Damaeidae) is described from Russia, based on adult and juvenile instars collected from bark of Acer platanoides and soil-litter of mixed and broadleaf forests in European part of Russia and Western Siberia. The adult of Spatiodamaeus kalugaensis sp. nov. is similar to S. nortoni (Bayartogtokh, 2004) comb. nov. in having epimeral neotrichy but differs from the latter by the presence of the parastigmatic tubercle Sa, the form of the parastigmatic tubercle Sp and the notogastral setae c1, c2, and the barbulation of the rostral, epimeral, anogenital, and notogastral setae of p-series. Comparisons between juvenile instars of the new species and the known juveniles of Spatiodamaeus and Epidamaeus are presented.

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.

Ontogenetic instars of the oribatid mite Tyrphonothrus digeluensis sp. nov. (Acari, Oribatida, Malaconothridae) from Ethiopia.

A new species of the genus Tyrphonothrus (Oribatida, Malaconothridae) is described from Ethiopia, based on adult and juvenile instars; it is collected from mosses on the swamp at the top of the mountain in Arsi Mountains National Park. Tyrphonothrus digeluensis sp. nov. differs from the related species Tyrphonothrus obesus (Yamamoto & Coetzee, 2004) and T. rectus (Yamamoto & Coetzee, 2004) by the pubescence of exobothridial, epimeral, anoadanal, and some notogastral setae. Comparison between juvenile instars of the new species and the known juveniles of Malaconothridae is presented.

Taxonomic contribution to the knowledge of the oribatid mite family Scheloribatidae (Acari, Oribatida), with description of three new species from Vietnam.

Three new oribatid mite species of the family Scheloribatidae (Oribatida)Dometorina (Dometorina) robusta sp. nov., Phylloribatula latiseta sp. nov., Scheloribates (Scheloribates) paraflagellisetosus sp. nov.are described, based on adults collected from tree branches of Dipterocarpus alatus in southern Vietnam. Representatives of Dometorina (Dometorina) and Phylloribatula are recorded in the Vietnamese fauna for the first time. An identification key to the known species of Phylloribatula is provided.

Three new species of Pergalumna (Acari, Oribatida, Galumnidae) from Malawi, with updated identification key to known species of the genus from the Afrotropical region.

Three new species of Pergalumna (Pergalumna) (Oribatida, Galumnidae)P. (P.) dedzaensis sp. nov., P. (P.) paratsavoensis sp. nov. and P. (P.) parafrater sp. nov.are described from sifting litter of highland forests in Central and Southern Malawi. An identification key to known species/subspecies of the genus from the Afrotropical region is presented.

Two new species of Cunaxa (Acari: Prostigmata: Cunaxidae) from Vietnam.

Two new mite species of the genus Cunaxa are described based on female specimens in Vietnam: Cunaxa oblongostriata sp. n. and C. sergeyenkoi sp. n. (Acari: Prostigmata: Cunaxidae). Cunaxa oblongostriata sp. n. differs from the related species, C. setirostris (Hermann, 1804), in having the propodosomal shield triangular and longitudinal striae between dorsal setae d1d1; while in C. setirostris, the propodosomal shield is trapezoidal and striae between setae d1d1 are transversal. Cunaxa sergeyenkoi sp. n. differs from two related species, C. bochkovi Khaustov Kuznetsov, 1998 and C. womersleyi Baker and Hoffmann, 1948, by the basifemoral chetotaxy of legs IIV: 4-4-2-1 sts; while C. bochkovi and C. womersleyi have the basifemoral chaetotaxy IIV: 3-3-3-1 sts and 4-4-3-1 sts, respectively.

Luisumaoppia molinoensis gen. nov., sp. nov. (Acari, Oribatida, Oppiidae) from Peru.

A new oribatid mite genus, Luisumaoppia gen. nov. (Oribatida, Oppiidae, Oppiinae), with Luisumaoppia molinoensis sp. nov. as type species, is described from soil and leaf litter in primary mountain cloud forest in Andes, Peru. It differs from the other genera of Oppiidae by the presence of modified (nearly straight), directed backwards leg claws located on bent pretarsi. The relationships of Luisumaoppia gen. nov. with the related genera in Oppiinae are presented.

An interesting sexually dimorphic species, Chamobates callipygis Pavlichenko, 1991 (Acari, Oribatida, Chamobatidae), with remarks on sexual dimorphism in Ceratozetoidea.

Based on materials from the leaf litter of a mixed forest in Crimea, a new diagnosis for the sexually dimorphic species, Chamobates callipygis Pavlichenko, 1991, is presented to accommodate its previously unreported females. This is the only species in Chamobatidae showing a distinct sexual dimorphism, which is expressed by the posterior porose region on the notogaster, such that males only have a large protuberance on the posterior part of notogaster bearing a pair of fused porose areas A3, and a densely striated region behind them. The specific function of this structure is not yet known, but the sexual dimorphism is presumably involved in pheromonal communication facilitating sperm transfer. Also, the males of this species have a few transverse striations in the dorsomedial part of notogaster (at level of porose areas A1 and A2). Further, we discuss all cases of sexual dimorphism in the superfamily Ceratozetoidea, and the possible function of this dimorphism.

The second species of the genus Ivoria Kontschán, 2019: description of Ivoriaalourouai sp. nov. from Ivory Coast (Acari, Mesostigmata, Urodinychidae).

A new Ivoria species (Ivoriaalourouai sp. nov.) is described from Ivory Coast based on five females. The new species differs from the previously described congener (Ivoriataienesis Kontschán, 2019) based on the shape of female genital shield, dorsal setae, centro-caudal part of the marginal shield and peritremes.

Taxonomy of European Damaeidae (Acari, Oribatida) XI. European species of the genus Piribelba Miko 2021: redescriptions of P. rossica (Bulanova-Zachvatkina, 1957) and P. piriformis (Mihelcic, 1964) using morphology and DNA sequence data.

Two closely related species of the genus Piribelba (Oribatida, Damaeidae) are redescribed based on morphology of adults and developmental instars. Redescription of P. rossica (Bulanova-Zachvatkina, 1957) is based on specimens collected in Russia, including specimens identified by Bulanova-Zachvatkina; redescription of P. piriformis (Mihelcic, 1964) is based on specimens collected in Europe, including Mihelcic's types. COX1 sequence barcoding of P. piriformis and P. rossica indicated that they are distinct species, having 12.0% uncorrected p-distances and 13.3% Kimura two-parameter distances (K2P). Based on the morphological and genetical differences, the synonymy of P. rossica and P. piriformis is rejected. A key to known species of Piribelba is provided.

Ontogenetic instars of Elliptochthonius profundus Norton, 1975 (Acari, Oribatida, Elliptochthoniidae), with remarks on juveniles of the superfamily Parhypochthonioidea.

The morphology of juvenile instars of the mite Elliptochthonius profundus Norton, 1975 (Oribatida, Elliptochthoniidae) is studied. Comparative characteristics of juveniles of the representative genera in the superfamily Parhypochthonioidea is given based on our own data and available literature sources, and the major characteristics of larvae and nymphs are presented. It can be summarized that the juveniles of parhypochthonioides have the following character states: body trichoid, i.e., the postpedal scissure of gastronotum is clearly developed; body colour whitish or pale yellowish, lacking the strong cuticular sclerotization, where the flesh cuticle is sparsely foveolate or weakly microtuberculate; the juveniles of the different genera are generally similar, but differ from one another in the shape of bothridial seta, number of gastronotic setae, setations of gnathosomal, anogenital and epimeral regions and legs, development of the genital and aggenital plates and peranal segment.

Ontogenetic instars of Lepidacarus maafushiensis sp. nov. from the Maldives, with remarks on morphological ontogeny of Lohmanniidae (Acari, Oribatida).

Although the juvenile instars of oribatid mite family Lohmanniidae are well known compared to the other families of the infraorder Enarthronota, information on morphological ontogeny most known species is still lacking. Herein, a new species of the genus Lepidacarus is proposed from soil-litter of the Maafushi Island, Maldives, based on all ontogenetic instars. A comparative analysis of ontogenetic instars of species belonging various genera of Lohmanniidae is given, and the major characteristics of juvenile instars of 21 species are presented. From this analysis, it can be generalized that the juvenile morphologies of lohmanniid genera are quite similar and uniform, there is no significant features separating different genera of Lohmanniidae, and the juveniles of various genera differ from one another in the same characteristics as the adults.