Description of an arboreal oribatid mite species of the genus Ovobates (Acari, Oribatida, Oribatulidae), based on adult and nymphs from Vietnam

Four new oribatid mite species of the superfamily Galumnoidea, Pergalumna paradecoratissima sp. nov., Pergalumnaparalongisetosa sp. nov., Pergalumna ecuadorensis sp. nov. and Galumnopsis lanceosensilla sp. nov., are described fromEcuador. The genus Galumnopsis is recorded for the first time for the Ecuador. Pergalumna paradecoratissima sp. nov.is very similar in having the combination of foveolate prodorsum, striate notogaster, setiform sensilli, interlamellar setaeshorter than lamellar and rostral setae, absence of anterior notogastral margin and three pairs of notogastral porose areas,to Pergalumna decoratissima Pérez-Íñigo & Baggio, 1986 from Brazil, however it differs from the latter by morphologyof rostrum, body size, surface of anal plates and length of epimeral setae. Pergalumna paralongisetosa sp. nov. is verysimilar in having the combination of setiform sensilli, long prodorsal setae, absence of anterior notogastral margin, threepairs of notogastral porose areas and long adanal setae ad 1 and ad 2 to Pergalumna longisetosa Balogh, 1960 from CentralAfrica, however it differs from the latter by body size, lengths of sensilli and interlamellar setae, absence of medial pore,length of epimeral setae. Pergalumna ecuadorensis sp. nov. can be distinguished from all similar species by having theround rostrum, setiform sensilli, long and setiform prodorsal setae, absence of anterior notogastral margin, smooth bodysurface and three pairs of oval notogastral porose areas, and by the very long interlamellar setae. Galumnopsis lanceosen-silla sp. nov. can be distinguished from all similar species (with smooth body surface) by the morphology of sensilli which are lanceolate, with tooth in distal part.

A new species of Galumnidae, Dimidiogalumna grandjeani sp. nov., is described from bird’s nest (Black-andred Broadbill, Cymbirhynchus macrorhynchos) in southern Vietnam. It is the first member of this genus recorded from the Oriental Region. The new species is most similar to D. comoroensis Mahunka, 1994 in having the elongate notogastral porose areas Aa, however, it differs from the latter by the presence of four pairs of notogastral porose areas and the absence of anterior notogastral margin and ridges on anal plates. An identification key to the known species of Dimidiogalumna is given.

The morphology of the juvenile stages of the mite Birsteinius clavatus (Oribatida, Liacaridae) is described and illustrated. The body and legs possess a granular cerotegument. The nymphs possess exuviae (this fact is mentioned for Liacaridae for the first time). Sensilla are well developed, possessing elongate spindle-shaped hairs, with noticeable swelling and flagellate tip. Interlamellar setae are long, setiform in larva, and small thornshaped in nymphs. Gastronotic setae are long, barbed, possessing flagellate tips. Setal formulae of the body (larva to tritonymph) are the following: genital (0-1-2-4), aggenital (0-0-1-1), anal (0-0-0-2), adanal (0-0-3-3), gastronotic (11-12-12-12) and epimeral setae (3-1-2, 3-1-2-1, 3-1-2-2, 3-1-3-3). Palpal tarsus possesses 8 setae and a single solenidion; the solenidion is not fused with any seta. Femora I and IV possess very long seta. Juvenile stages of B. clavatus combine morphological features of Liacarus (Liacaridae) and Gustavia (Gustaviidae). Norton’s hypothesis (1983) on phylogenetic relations in Gustavioidea is discussed.

Two new species of oribatid mites, Ghilarovizetes labaheensis sp. nov. and Ghilarovizetes sichuanensis sp. nov. are described from China based on adult morphology. Ghilarovizetes labaheensis sp. nov. is characterized by rounded rostrum, lamella short and wide, tutorium narrow and concave medially, notogastral setae short-size as long as bothridial setae and four pairs of notogastral porose areas. The adult instar of Ghilarovizetes sichuanensis sp. nov. has large body size, rostrum concave medially, lamella long and narrow, notogastral setae minute and five pairs of notogastral porose areas (porose areas A1 divided into two parts).

A new species of oribatid mite of the genus Pergalumna (Oribatida, Galumnidae) is described from litter and soil materials in Sumatra, Indonesia. Pergalumna paraindistincta sp. n. is morphologically most similar to Pergalumna indistincta Ermilov & Anichkin, 2011, Pergalumna pertrichosa Mahunka, 1995 and Pergalumna sura Balogh, 1997; however, the new species differs from Pergalumna indistincta by the smaller body size, presence of long adanal setae ad1, and large, single median pore in females and males; from Pergalumna pertrichosa by the smaller body size, presence of three pairs of notogastral porose areas, elongated A1 and minute anal setae; from Pergalumna sura by the presence of strong adanal setae ad1, large, single median pore in females and males, and shorter bothridial setae. Furthermore, Pergalumna hawaiiensis hawaiiensis (Jacot, 1934) and Pergalumna panayensis Ermilov & Corpuz-Raros, 2015 are recorded for the first time in the Indonesian fauna. An identification key to the known species of Pergalumna in the Oriental region is given.

A new species of the genus Scheloribates (Oribatida, Scheloribatidae) — S. (Scheloribates) arsizonensis n. sp. — is described from Ethiopia, based on adult and juvenile instars, collected from litter and green moss in Arsi Mountains National Park. Adults of the new species differ from S. praestantissimus praestantissimus (Berlese, 1916) in having fusiform, distally pointed bothridial seta, the absence of prolamella, and the presence of well-developed notogastral setae p<sub>1</sub>. The comparison of juveniles of the new species with juveniles of other Scheloribates species is presented. Juveniles of the new species can be distinguished from the other known juveniles of S. (Scheloribates) by the presence of two strong, long, longitudinal, dorsolateral folds on the gastronotum in all instars, long gastronotic seta c<sub>3</sub>, which is distinctly longer than other gastronotic setae in nymphal instars, the presence of vestigial gastronotic seta h<sub>3</sub> in larva, and in the absence of aggenital setae in deutonymph.

The morphology of juvenile stages of Eremaeus cordiformis Grandjean, 1934 is redescribed and illustrated, and those of Eueremaeus laticostulatus Bayartogtokh, 2003 and Proteremaeus punctulatus Bayartogtokh, 2000 are described and illustrated for the first time. The juveniles of these species differ from each other mainly by the presence of distinct prodorsal ridges in the central part of the prodorsum, shape and distribution of some setae, and number of adanal and anal setae. The larva of Er. cordiformis has these ridges, whereas other species lack them. Eueremaeus laticostulatus has relatively long and barbed prodorsal seta in in the larva and most gastronotal setae similarly ornamented in all juveniles, whereas other species have these setae short and smooth. The nymphs of Er. cordiformis and Eu. laticostulatus have three pairs of posterior gastronotal setae (p1, h1, h2), which are inserted close to each other in transverse row, whereas those of P. punctulatus have only two pairs (p1, h1) there, and seta h2 is inserted far from seta h1 and closer to seta p2. The nymphs of all species lose dorsal gastronotal setae of d-series and carry the exuvial scalps of previous instars directly on the glabrous gastronotum mainly due to lateral folds. The nymphs and adult of P. punctulatus have three pairs of adanal setae and two pairs of anal setae, whereas those of other species have at least five pairs of each series. The adult of Er. cordiformis has 11 pairs of notogastral setae, whereas other species investigated here have 10 pairs. The adults of all species have lamellar costulae on the prodorsum, but in P. punctulatus they are more widely separated than in other species. At present the systematic position of Proteremaeus is controversial in the literature, but the morphology of juveniles and adult of P. punctulatus investigated here confirms the membership of this genus in the Eremaeidae. A number of morphological characters support the separation of Er. hepaticus and Er. cordiformis and we provisionally reject their synonymy, until the type or topotypic material is compared.

The morphological ontogeny of Amerobelba decedens Berlese, 1908 is described and illustrated. In the adult of this species, the bothridial seta is setiform, unilaterally ciliate, notogastral setae are short and barbed, and sexual dimorphism is present on tarsus IV. Most prodorsal setae of juveniles are short and smooth, except for medium-sized ro, barbed in the nymphs. The bothridial seta is long, setiform and barbed in distal part. The gastronotal setae are of medium size and barbed, except for smooth c1 and c2 in all juveniles, and smooth of d-series and short h2 in the larva. Setae c1 and c2 are inserted on large macrosclerite, and other gastronotal setae are inserted on individual microsclerites, except for h2 in the larva. The anal and anogenital regions are reticulate, and adanal setae are inserted on individual microsclerites. The nymphs are quadrideficient and eupheredermous, i.e. they lose setae of d-series and carry the exuvial scalps of previous instars. In this species, seta d accompanies solenidion σ on genu III and φ on tibia III and IV, both in the juveniles and adults. It is a xero-thermophilous species, with one generation per year.

The present study is based on oribatid mite materials (Acari, Oribatida) collected from Macao SAR, southern China during 2016 to 2018. A list of identified taxa, including 25 species from 23 genera and 14 families, is presented; of these, 11 species and 1 genus are recorded for the first time in the fauna of this country, and 1 species is recorded for the first time in the Oriental region. The taxonomic data on two species of the family Galumnidae is provided. A new species, Dimiodiogalumna ilhaverdeensis Ermilov sp. nov. is described; it differs from Dimidiogalumna comoroensis Mahunka, 1994 by the presence of four pairs of notogastral porose areas and one strium on genital plates, and the absence of ridges on anal plates. The systematic placement of Acrogalumna bipartita Aoki & Hu, 1993 is discussed, resulting in the following taxonomic proposal: Allogalumna bipartita (Aoki & Hu, 1993) comb. nov.; the supplementary description of this species is presented based on specimens from China.

Two new species of the genus Galumna (Oribatida, Galumnidae) are described from the Antigua and Aruba Islands (Lesser Antilles). Galumna ( Galumna ) antiguaensis sp. nov. is morphologically most similar to G. ( Galumna ) tetraporosa Ermilov, Martens & Tolstikov, 2014, but differs by the smaller body size, presence of three pairs of notogastral porose areas, short interlamellar seta and parallel lamellar and sublamellar lines. Galumna ( Neogalumna ) harrysmiti sp. nov. is morphologically most similar to G. ( Neogalumna ) curviporosa (Balakrishnan, 1986), but differs by the minute interlamellar seta, unusual long postanal porose area, band-like porose areas A2 and A3 , paraanal position of adanal lyrifissure and the presence of a median pore and longer bothridial seta.

A new species, Fuscozetes kamchatkicus sp. nov., including its morphological ontogeny, from Kamchatka Peninsula (Russia) is described and illustrated. The adult of this species is smaller and slimmer than congeners and has longer prodorsal seta le than in; in other species in is longer than le. In F. kamchatkicus the shape of the translamella varies (usually is present, but may be narrow as a line or absent), while in other species the translamella is present. The juveniles of F. kamchatkicus differ from congeners by several morphological characters that are unique in Fuscozetes Sellnick, 1928, e.g. they lack a humeral organ, which is present in other species. The larva lacks a humeral macrosclerite, whereas other species have it. In F. kamchatkicus the gastronotal setae are inserted on unsclerotized integument, whereas in other species they are inserted either on the gastronotal shield or microslerites. The nymphs of F. kamchatkicus have a humeral macrosclerite and a gastronotal shield, which is typical of Fuscozetes and Sphaerozetinae (Ceratozetidae), but the humeral macrosclerite bears seta c1, while setae c2 and c3 are inserted on unsclerotized integument, whereas in other species the humeral macrosclerite is glabrous and setae c2 and c3 are inserted on microsclerites. In F. kamchatkicus setae p2 and p3 are inserted on unsclerotized integument, whereas in other species they are inserted on a macrosclerite. In the juveniles of F. kamchatkicus most gastronotal setae are barbed, except of the d-series in the nymphs, which are thinner than other gastronotal setae and smooth. The diagnosis of Fuscozetes is modified and enlarged with the morphological characters of juveniles.

The morphological ontogeny of Anachipteria magnilamellata (Ewing, 1909) is described and illustrated. The adult of this species lacks the anterior pteromorphic projection, and has 10 pairs of notogastral setae, with longer c2 and la, and four pairs of porose areas, with the largest Aa. Genua I and II of A. magnilamellata have an anteroventral projection, seta v'' on femur II is longer than bv'', seta l' on femur III is short and leg tarsi are heterotridactylous, with smooth claws. The prodorsal setae of juveniles are minute, except short rostral seta (ro), whereas the gastronotal setae are short or medium sized and barbed. Seta h1 is absent from the larva. The leg segments of juveniles are stocky, and leg claws and most leg setae are smooth. Seta d at solenidion φ on tibia IV is present. The morphology of A. magnilamellata is compared with that of congeners. We consider Weigmanniella Subías, 2010 as a junior synonym of Anachipteria.

The larva and nymphs of (Banks, 1895) (Oribatida, Galumnidae) are described, based on material collected from bogs and pine-birch forests in Western Siberia, Russia. The juvenile instars are characterized by the following morphological characters: rostrum acute or narrowly rounded, rostral and lamellar setae medium-sized, interlamellar and exobothridial setae short and erect, bothridial seta long, lanceolate and barbed, a gastronotic porose areas present, setae of gastronotic macrosclerite minute, gastronotic seta c longer than c and c, gastronotic setae each with a small sclerite at base, a median pore present, lateral part of body with several oblong sclerites, anterior margin of coxisternum overlapping medially, posteroventral region with one pair of large sclerites, some leg segments with thick setae. Differences between the juvenile instars of and other known species are listed. Identification keys to the larvae and tritonymphs of are provided.

The morphological ontogeny, distribution and ecology of Damaeus torquisetosus (Mihelcic, 1955) and Epidamaeus puritanicus (Banks, 1906) were investigated. In the juveniles of D. torquisetosus the legs are longer than the main body, especially leg IV, the prodorsal setae are of medium size, except for short seta in in nymphs, the dorsal setae on gastronotum are long or very long, except for distinctly shorter setae c3 and h2 in larva, seta h3 absent in larva, most gastronotal setae are curved, finely barbed, with flagellate distal part and inserted on apophyses, the cornicle is straight and situated between setal pair lm and epimeral setae are of different lengths. Juveniles of D. torquisetosus differ from the known juveniles of other Damaeus species in the following: absence of seta h3 in the larva, but present in other Dameus species, seta c3 in nymphs is of medium size whereas in most other species it is short. In the juveniles of E. puritanicus legs I, III and IV are as long or slightly longer...

ABSTRACTA new species of the genus Angulogalumna (Oribatida, Galumnidae) is described from leaf litter in evergreen rain forest in the Montagne d’Ambre National Park of North Madagascar. Angulogalumna grishinae sp. nov. differs from Angulogalumna asiatica and Angulogalumna areolata by the presence of setiform bothridial seta, localization of lamellar seta medial to lamellar line, three pairs of notogastral porose areas, and notogastral porose area Aa elongate oval, A1 boomerang-form or banana-shaped, and by the absence of dorsosejugal suture and median pore. An identification key and data on distribution and ecology of known species of Angulogalumna are presented.http://www.zoobank.org/urn:lsid:zoobank.org:pub:E6193F26-F6AE-4759-9CA3-F6780D75452D