taxonID	type	description	language	source
038387FD0727B51FFF66937F87F15FFB.taxon	type_taxon	Type species: Eremaeus patella Berlese, 1886	en	Ermilov, Sergey G., Kirnev, Vyacheslav (2025): Ontogenetic instars of a new species of the genus Scapheremaeus (Acari, Oribatida, Cymbaeremaeidae) from Vietnam. Zootaxa 5740 (1): 66-79, DOI: 10.11646/zootaxa.5740.1.7, URL: https://doi.org/10.11646/zootaxa.5740.1.7
038387FD0727B517FF669393802B5EBD.taxon	description	(Figs 1 – 7)	en	Ermilov, Sergey G., Kirnev, Vyacheslav (2025): Ontogenetic instars of a new species of the genus Scapheremaeus (Acari, Oribatida, Cymbaeremaeidae) from Vietnam. Zootaxa 5740 (1): 66-79, DOI: 10.11646/zootaxa.5740.1.7, URL: https://doi.org/10.11646/zootaxa.5740.1.7
038387FD0727B517FF669393802B5EBD.taxon	materials_examined	Type material. Holotype (female) and four paratypes (one male and three females) were collected from southern Vietnam, Dong Nai Province, Dong Nai Biosphere Reserve, Cat Tien National Park, 11 ° 25 ’ N, 107 ° 25 ’ E, about 130 m a. s. l., branches from the Lauraceae tree at the height of 25 m, 3. XII. 2024 (collected by V. M. Salavatulin). The holotype is deposited in the collection of the Senckenberg Museum of Natural History, Görlitz, Germany. Four paratypes are deposited in the collection of the University of Tyumen, Museum of Zoology, Tyumen, Russia. All specimens are preserved in 70 % solution of ethanol with a drop of glycerol. Additional (non-type) material. Twenty adults (seven males and 13 females) and 26 juvenile instars (seven larvae, five protonymphs, nine deutonymphs, and five tritonymphs) were collected in the same location and on the same tree as the holotype and paratypes. All specimens (in 70 % solution of ethanol with a drop of glycerol) are in the personal collection of S. G. Ermilov.	en	Ermilov, Sergey G., Kirnev, Vyacheslav (2025): Ontogenetic instars of a new species of the genus Scapheremaeus (Acari, Oribatida, Cymbaeremaeidae) from Vietnam. Zootaxa 5740 (1): 66-79, DOI: 10.11646/zootaxa.5740.1.7, URL: https://doi.org/10.11646/zootaxa.5740.1.7
038387FD0727B517FF669393802B5EBD.taxon	diagnosis	Diagnosis. Adult. Body length 315 – 360. Surface and thick cerotegument foveolate. Costula medium-sized, with minute, rounded cusp. Transcostula lineate. Rostral seta medium-sized, setiform, slightly barbed. Lamellar seta short, simple. Interlamellar and exobothridial setae absent. Bothridial seta with black, club-shaped and flattened head covered by longitudinal ridges. Anterior notogastral margin concave medially. Circumdorsal scissure of notogaster completely absent. Eight pairs of notogastral setae developed, c, dm, p 2, and p 3 short, setiform, slightly swollen distally, lp and h 1 – h 3 longer, phylliform. Epimeral setal formula 2 - 1 - 2 - 2. Anogenital setal formula 6 - 1 - 2 - 2. All epimeral and anogenital setae comparatively short, nearly smooth, 1 b, 3 b, 4 a, and g 1 longer than others. Adanal lyrifissure close and parallel to anal plate. All leg tarsi with three claws. Some setae of tarsi I – IV slightly swollen distally. Some setae of tibiae, genua, and femora phylliform. Homology of leg setae and solenidia indicated in Table 1. Juvenile instars. Gastronotic (except dorsocentral region in nymphal instars), anogenital, and sternal epimeral regions plicate. Body and legs covered by thick layer of ribbon-shaped or ridge-like cerotegument including foveolae (rostral and interbothridial regions, legs) and microgranules. Costular and transcostular lines slightly developed. Rostral, lamellar, and exobothridial setae simple. Interlamellar seta phylliform. Bothridial seta with club-shaped, flattened head covered by longitudinal ridges. Nymphal instars carrying exuvial scalps of previous instars. Larva with 10 pairs of gastronotic setae (c 1 and da absent), c 2, c 3, dm, and dp short, setiform, slightly swollen distally, smooth, other setae longer, phylliform, with barbs and ridges. Nymphal instars with 11 pairs of gastronotic setae (c 1, da, dm, and p 3 absent), c 2, c 3, and dp short, setiform, slightly swollen distally, smooth, p 1 and p 2 short, setiform, smooth, other setae longer, phylliform, with barbs and ridges. Epimere I in nymphal instars with two pairs of setae (1 c absent). Two pairs of adanal setae developed (ad 3 absent). Homology of leg setae and solenidia indicated in Table 1.	en	Ermilov, Sergey G., Kirnev, Vyacheslav (2025): Ontogenetic instars of a new species of the genus Scapheremaeus (Acari, Oribatida, Cymbaeremaeidae) from Vietnam. Zootaxa 5740 (1): 66-79, DOI: 10.11646/zootaxa.5740.1.7, URL: https://doi.org/10.11646/zootaxa.5740.1.7
038387FD0727B517FF669393802B5EBD.taxon	description	Description of adult. Measurements. Body length 360 (holotype), 315 (male paratype), 330 – 360 (female paratypes). Notogaster width 180 (holotype), 150 (male paratype), 165 – 180 (female paratypes). Integument (Figs 6 A – D; 7 A). Colour brown. Surface (except subcapitular rutellum and gena, leg genua I – IV and trochanters I, II) foveolate (diameter of foveola up to 7). Body and legs covered by thick, tightly adhering layer of foveolate cerotegument. Prodorsum (Figs 1 A, C; 6 A, B, D). Rostrum broadly rounded. Costulae medium-sized (slightly shorter than half of prodorsum), lineate, convergent basally and forming X-shaped ridge structure in interbothridial region. Cusp of costula weakly developed, rounded, bearing lamellar seta. Transcostula lineate, sometimes slightly convex medially. Transverse (front of transcostula) and lateral (parallel to costula) ridges well developed. Rostral seta (30 – 34) setiform, slightly barbed. Lamellar seta (4 – 6) simple. Interlamellar and exobothridial setae absent. Bothridial seta (37 – 41) with short stalk and longer, black, club-shaped and flattened head covered by longitudinal ridges. Notogaster (Figs 1 A, C; 6 C). Anterior notogastral margin concave medially. Circumdorsal scissure completely absent, but dorsocentral region of notogaster with two longitudinal depressions. Lenticulus distinct. Humeral process narrowly triangular (but illusory it appears like a tubercle in dorsal view). Eight pairs of setae developed. Of them, c, dm, p 2, and p 3 (11) slightly swollen distally, other setae (lp, h 1 – h 3 15 – 17) phylliform, with short stalk and rounded distally, roughened head. Circumdorsal region with one pair of setae (dm). Opisthonotal gland opening and all lyrifissures (except ia and ip) well visible. Gnathosoma (Figs 1 B; 2 A – C; 6 C; 7 A). Subcapitulum size 71 – 75 × 45 – 49. Subcapitular setae (a, m 11 – 13; h 13 – 15) setiform, roughened. Two pairs of adoral setae represented by microsetae (4). Length of palp 45 – 49. Palp setal formula 0 - 2 - 1 - 3 - 9 (+ ω). Postpalpal seta (4) spiniform. Length of chelicera 71 – 75. Cheliceral setae (cha 19; chb 15) setiform, barbed. Epimeral and lateral podosomal regions (Fig; 1 B, C; 3 C, D). Epimeral setal formula 2 - 1 - 2 - 2. Setae (1 b, 3 b, 4 a 19 – 22; 1 a, 2 a, 3 a, 4 b 11) setiform, nearly smooth. Anogenital region (Figs 1 B, C; 6 C). Anogenital setal formula 6 - 1 - 2 - 2. Genital (g 1 19 – 22; g 2 – g 6 11), aggenital (11), anal (11), and adanal (11) setae setiform, nearly smooth. Two pairs of adanal setae developed (ad 3 absent). Adanal lyrifissure close and parallel to anal plate. Legs (Figs 2 D – G; 6 A – D). Heterotridactylous. Claws slightly barbed on dorsal side. Lateroparaxial porose area on femora I – IV and on trochanters III, IV well visible. Formulas of leg setation and solenidia: I (0 - 4 - 2 - 4 - 16) [1 - 2 - 2], II (0 - 4 - 2 - 3 - 15) [1 - 1 - 1], III (1 - 2 - 1 - 3 - 15) [1 - 1 - 0], IV (0 - 2 - 2 - 3 - 11 / 12) [0 - 1 - 0]. Homology of setae and solenidia indicated in Table 1. Many setae of tarsi I – IV slightly swollen distally. Setae l " of tibiae I, II, l' and l " of genua I, II, l' of genu III, d, l' and l " of femora I, II, d and ev' of femur III phylliform. Descriptions of juvenile instars. Measurements. Body length of LA 180 – 195, PN 210 – 225, DN 240 – 270, TN 300 – 390. Body width of LA 90 – 105, PN 120 – 135, DN 135 – 165, TN 165 – 195. Integument (Figs 7 C, D). Colour gray to light brownish, partially covered by granulate cerotegument. Rostral and interbothridial regions slightly and densely foveolate (diameter of foveola up to 4). Gastronotic (except dorsocentral region in nymphal instars), anogenital, and sternal epimeral regions plicate. Medioposterior part of gastronotum in TN sparsely foveolate (diameter of foveola up to 7). Body and legs covered by thick layer of ribbon-shaped or ridge-like cerotegument including foveolae (rostral and interbothridial regions, legs) and microgranules. Prodorsum (Figs 3 A, C; 4 A – C; 7 C, D). Triangular, about 3 / 5 (in larva) to 1 / 2 (in nymphs) length of gastronotum in lateral view. Rostrum broadly rounded. Costular and transcostular lines slightly developed. Lateral longitudinal ridge well developed. Rostral (LA, PN 7; DN 9 – 11; TN 11), lamellar (LA, PN, DN, TN 4), and exobothridial (LA, PN, DN, TN 2) setae simple, ro inserted on distinct tubercle, le sometimes vaguely swollen distally. Interlamellar seta (LA, PN, 11; DN 11 – 13; TN 15) phylliform, with barbs and ridges. Bothridial seta (LA 26 – 30; PN, DN 30 – 34; TN 41 – 49) with short stalk and longer, club-shaped, flattened head covered by longitudinal ridges. Gastronotic region (Figs 3 A, C, D; 4 A – C; 7 C, D). Prodorsum and gastronotum well separated. Nymphal instars carrying exuvial scalps of previous instars. Larval scalp with seven pairs of setae (c 2, la, dm, lm, dp, lp, h 1). Of them, setae c 2, dm, and dp minute, slightly swollen distally, smooth, other setae longer, phylliform, rounded or narrowed distally, with barbs and ridges. Nymphal scalps with eight pairs of setae (c 2, la, lm, dp, lp, h 1 – h 3). Of them, setae c 2 and dp minute, slightly swollen distally, smooth, other setae longer, phylliform, rounded or narrowed distally, with barbs and ridges. Larva with 10 pairs of gastronotic setae (c 1 and da absent). Length of setae in LA: lp, h 1 19 – 22; lm, h 2 15; la 11; h 3 7; c 2, c 3, dm, dp 4. Setae c 2, c 3, dm, and dp slightly swollen distally, smooth, h 2 and h 3 setiform, smooth, other setae phylliform, rounded or narrowed distally, with barbs and ridges. Nymphal instars with 11 pairs of gastronotic setae (c 1, da, dm, and p 3 absent). Length of setae in PN: lp, h 1 – h 3 26 – 34; lm 15; la, p 1, p 2 11; c 2, c 3, dp 4; DN: lp, h 1 – h 3 37 – 45; lm 15; la, p 1, p 2 11; c 2, c 3, dp 4; TN: lp, h 1 – h 3 49 – 60; lm 15 – 17; p 1, p 2 13 – 15; la 11 – 13; c 2, c 3, dp 6. Setae c 2, c 3, and dp slightly swollen distally, smooth, p 1 and p 2 setiform, smooth, other setae phylliform, rounded or narrowed distally, with barbs and ridges. Line of dehiscence not visible. Opisthonotal gland opening and all cupules (except ip) well visible. Gnathosoma. Subcapitulum size in LA 37 – 41 × 34 – 37; PN 41 – 45 × 37 – 41; DN 45 – 49 × 41 – 45; TN 52 – 56 × 45 – 52. All subcapitular setae setiform, roughened. Length of subcapitular setae a, m in LA 4; PN, DN 5; TN 7 – 11. Length of subcapitular seta h in LA 4; PN 5; DN 5 – 7; TN 9 – 13. Two pairs of adoral setae represented by microsetae in all instars (1 – 2). Palp length in LA, PN 30; DN 34; TN 37 – 41. Postpalpal seta (2) spiniform in all instars. Second seta on palp femur developed in LA. Chelicera length in LA 41; PN 41 – 45; DN 49; TN: 52 – 56. Both cheliceral setae setiform, barbed. Length of cheliceral seta cha in LA, PN 11; DN 15; TN 15 – 19. Length of cheliceral seta chb in LA, PN 7; DN 11; TN 11 – 13. Epimeral and lateral podosomal regions (Figs 3 B, C; 5 A – C). Setal formulas for epimeres: LA 3 - 1 - 2 (1 c as typical scale covering Claparède’s organ); PN 2 - 1 - 2 - 1; DN, TN 2 - 1 - 2 - 2. Length of setae in LA, PN 7; DN 7; TN: 9 – 13. All setae simple. Anogenital region (Figs 3 B, C; 5 A – C). Ontogeny of genital (PN 5; DN, TN 7), aggenital (DN, TN 7), anal (TN 7), and adanal (DN, TN 11) setal formulas, LA to TN 0 - 1 - 3 - 5, 0 - 0 - 1 - 1, 0 - 0 - 0 - 2, 0 - 0 - 2 - 2, respectively. All setae simple. Two pairs of adanal setae developed in DN and TN (ad 3 absent). Paraproctal segments without setae. Cupules ih, ips, and iad appearing in normal ontogenetic pattern. Anal cupule not observed. Legs (Figs 3 E – G). Claw of each tarsus strong, slightly barbed on dorsal side. Ventroparaxial porose area on all femora well visible. Leg setal formulas in LA: I (0 - 2 - 3 - 4 - 14) [1 - 1 - 1], II (0 - 2 - 3 - 3 - 13) [1 - 1 - 1], III (0 - 2 - 2 - 2 - 13) [1 - 1 - 0]; PN: I (0 - 2 - 3 - 4 - 14) [1 - 1 - 2], II (0 - 2 - 3 - 3 - 13) [1 - 1 - 1], III (0 - 2 - 2 - 2 - 13) [1 - 1 - 0], IV (0 - 0 - 0 - 0 - 7) [0 - 0 - 0]; DN: I (0 - 3 - 3 - 4 - 14) [1 - 1 - 2], II (0 - 3 - 3 - 3 - 13) [1 - 1 - 1], III (1 - 2 - 2 - 2 - 13) [1 - 1 - 0], IV (0 - 2 - 2 - 2 - 12) [0 - 1 - 0]; TN: I (0 - 4 - 3 - 5 - 16) [1 - 2 - 2], II (0 - 4 - 3 - 5 - 15) [1 - 1 - 2], III (1 - 2 - 2 - 4 - 15) [1 - 1 - 0], IV (0 - 2 - 2 - 4 - 12) [0 - 1 - 0]. Homology of setae and solenidia indicated in Table 1.	en	Ermilov, Sergey G., Kirnev, Vyacheslav (2025): Ontogenetic instars of a new species of the genus Scapheremaeus (Acari, Oribatida, Cymbaeremaeidae) from Vietnam. Zootaxa 5740 (1): 66-79, DOI: 10.11646/zootaxa.5740.1.7, URL: https://doi.org/10.11646/zootaxa.5740.1.7
038387FD0727B517FF669393802B5EBD.taxon	discussion	Remarks. The adult instar of the new species is morphologically most similar to S. striatomarginatus Hammer, 1979 from Java in having four pairs of phylliform notogastral setae h 1 – h 3, and lm, and in the absence of the circumdorsal scissure. However, the new species differs from the latter by the presence (versus absence in S. striatomarginatus) of notogastral setae c and dm, and the morphology of the anterior margin of the notogaster (concave medially in S. naiensis versus straight in S. striatomarginatus).	en	Ermilov, Sergey G., Kirnev, Vyacheslav (2025): Ontogenetic instars of a new species of the genus Scapheremaeus (Acari, Oribatida, Cymbaeremaeidae) from Vietnam. Zootaxa 5740 (1): 66-79, DOI: 10.11646/zootaxa.5740.1.7, URL: https://doi.org/10.11646/zootaxa.5740.1.7
038387FD0727B517FF669393802B5EBD.taxon	etymology	Etymology. The specific name naiensis refers to the place of origin, Dong Nai Biosphere Reserve.	en	Ermilov, Sergey G., Kirnev, Vyacheslav (2025): Ontogenetic instars of a new species of the genus Scapheremaeus (Acari, Oribatida, Cymbaeremaeidae) from Vietnam. Zootaxa 5740 (1): 66-79, DOI: 10.11646/zootaxa.5740.1.7, URL: https://doi.org/10.11646/zootaxa.5740.1.7
