taxonID	type	description	language	source
038B87E0B134FFD76AAD50E2DBCB90E7.taxon	type_taxon	Type species: Sayanozercon mariannae sp. nov.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B134FFD76AAD50E2DBCB90E7.taxon	diagnosis	Diagnosis. The new genus is based on adult female and male material representing five newly described species. Adults of Sayanozercon gen. nov. can be distinguished from other genera of Zerconidae by the presence of an additional longitudinal latero-ventral shield extending between the peritrematal and ventrianal shields from setae r 3 to R 6; epistome with serrated central process with row of small median spines; smooth and acicular shape of all dorsal setae; podonotal setae z 1 and z 2 lost; unique morphology and sexual dimorphism of inguinal region with fibre brush of cuticular structure and two inguinal conspicuous poroids gvi and ivi; presence of pilus dentilis in fixed digit of chelicerae and sexual dimorphism of cheliceral denticulation – five teeth in female versus six teeth in male; sexual dimorphism of ventral chaetotaxy / porotaxy – setae st 5, Zv 1 lost in male and different location of gland gv 2.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B134FFD76AAD50E2DBCB90E7.taxon	description	Description of Sayanozercon gen. nov. Idiosomal dorsum. Large or mid-sized mites with rounded-oval or pear-shaped idiosoma, divided on two strongly sclerotised dorsal shields, without obvious ornamentation. All idiosomal setae smooth and pointed. Podonotal shield with 20 or 21 pairs of setae, setae z 1 and z 2 lost in all five species. Marginal seta r 1 shortest in r - series, inserted at dorsal side, r 3 seta is 3 – 4 times longer than r 1 seta. Three podonotal glands are present, with various location of gland gdz 5 (po 3) in other species and five pairs of lyrifissures: idj 1, idj 3, idz 4, ids 4, idj 6. Opisthonotal shield with 20 – 21 pairs of setae. Four podonotal glands present, with various location of gland gdZ 1 (Po 2) in other species. Opisthonotal shield with 13 pairs of lyrifissures: ids 6, idS 1, idz 6, idS 4, idZ 4, idJ 4, idJ 5, idJ 2, idJ 3, doubled idJ 1 and doubled idS 3. Posterodorsal cavities rounded curvings, all equal size, located at posterior margin of opisthonotal shield. Female venter. Additional latero-ventral shield is present, extending vertically from seta r 3 to R 6; with slight longitudinal reticulation. Peritrematal shields adjacent to additional latero-ventral shields anteriorly at level of coxae II and free at level of coxae III – IV. Peritrematal shield truncate at posterior margin, not fused with ventri-anal shield; with two conspicuous rounded poroids in inguinal region – gvi and ivi and fibre brush of cuticular structure. Peritrematal shields with smooth and pointed long setae r 3; with lyrifissures ip 1, ip 2 and gland gp from each side. Peritremes very short. Large pair of endopodal sclerites between coxae III – IV with pair of setae st 4 or outside sclerites. Adgenital sclerites presented each with 4 – 5 glands openings gv 2. Ventrianal shield free, wide, with 21 smooth and pointed setae. Anal opening with two pairs of lyrifissures on each valve. Male venter. Pair of latero-ventral shields shaped as in female, with reticulate ornamentation. Sternigenital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2; with four pairs of setae (st 1 – st 4), pair of st 5 setae not developed, three pairs of lyrifissures and pair of glands gv 1. Male peritrematal shields connected posteriorly to each other by fibre brush of cuticular structure; inguinal region with two pairs of conspicuous formations hollow inside — inguinal poroids gvi and ivi. Genital opening with two sclerites, eugenital setae present in S. mariannae sp. n. or not visible in other species. Ventrianal shield free, with multiple glands gv 2 located on anterior margin; with 19 smooth and pointed setae; pair of setae Zv 1 not developed. Gnathosoma. Epistome with irregularly serrated lateral edges, serrated middle process with median row of small spines and medial ridge located posteriorly to row of spines. Chelicera with long dorsal seta, lateral (antiaxial) and dorsal lyrifissures; with smooth arthrodial corona and leaf-shaped pilus dentilis; apical sensorial depression presents. Sexual dimorphism of chelicerae denticulation: five teeth in female and six teeth in male. Deutosternal groove with seven transverse denticulate rows. Corniculi horn-like, internal malae extending beyond corniculi. Palpal chaetotaxy 2 – 5 – 6 – 12 – 15 with five free segments; pilose setae on palp trochanter v 1 and v 2; on palp femur d 3, on palp genu al 2; palp tarsal claw two-tined. Legs. Legs of moderate length. All legs with pretarsi and paired claws. Pretarsus of legs II – IV with ambulacral stalk, tarsi I with sessile claws. Coxae I with dorsal incision, coxae II with antero-dorsal spine. Chaetotaxy of legs I – IV: coxae 2, 2, 2, 1; trochanters 6 (1 1 / 3 1), 5 (1 1 / 3 0), 5 (1 1 / 3 0), 5 (1 1 / 3 0); femora 13 (2 5 / 4 2), 11 (2 5 / 3 1), 6 (1 4 / 1 0), 6 (1 4 / 1 0); genua 13 (2 6 / 3 2), 11 (2 5 / 2 2), 10 (2 4 / 2 2), 10 (2 5 / 2 1); tibiae 14 (2 6 / 4 2), 10 (2 4 / 2 2), 9 (2 3 / 2 2), 9 (2 3 / 2 2); tarsi I – 49 (6 29 / 9 5), II – IV 18 (3 7 / 5 3). Chaetotaxy of legs I – IV is typical for Zerconidae (Halašková, 1969; Sikora, 2014). Legs of male without dimorphically modified setae.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B134FFD76AAD50E2DBCB90E7.taxon	etymology	Etymology. The genus name Sayanozercon reflects name of the Sayan Mountain in South Siberia, Russia. Gender feminine.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B134FFD76AAD50E2DBCB90E7.taxon	diagnosis	Species differential diagnosis. A large number of characters differ between species of new genus Sayanozercon as shown in Table 1 and are listed below. Idiosomal dorsum. Podonotal shield with 21 pairs of setae, seta s 1 presented in S. adelaidae sp. nov., S. mikhaili sp. nov., S. shoricus sp. nov. and with 20 pairs of setae in S. mariannae sp. nov., S. ergaki sp. nov., where seta s 1 is lost. Location of podonotal glands for all five species: gdj 2 (po 1) close to line connecting insertions of setae j 2 and z 3; gdj 4 (po 2) close to line connecting insertions of setae j 4 and z 4. Gland gdz 5 (po 3) usually located (for S. mariannae sp. nov., S. adelaidae sp. nov., S. ergaki sp. nov. and S. shoricus sp. nov.) close to line connecting insertions of setae z 5 and s 5, except for species S. mikhaili sp. nov., where it located near posterior edge of podonotal shield, close to line connecting insertions of setae s 5 and z 6. Opisthonotal shield with 20 pairs of setae in S. mariannae sp. nov., S. ergaki sp. nov., where four pairs of setae in J - series and 21 pairs of setae in S. adelaidae sp. nov., S. mikhaili sp. nov., S. shoricus sp. nov., where five setae in J - series. Seta J 3 is lost in S. mariannae sp. nov. and seta J 5 is lost in S. ergaki sp. nov. One species S. ergaki sp. nov. demonstrated sexual dimorphism of chaetotaxy: setae J 3, J 4 longest in female and shortest in male among setae in J- series. Opisthonotal adenotaxy presents different location of glands in other species. Location of opisthonotal gland gdZ 1 (Po 2) usually anterolateral to seta Z 1 (species S. mariannae sp. nov., S. adelaidae sp. nov., S. ergaki sp. nov. and S. mikhaili sp. nov.), except for species S. shoricus sp. nov., where it placed on line connecting insertions of setae Z 1 and Z 2.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B134FFD76AAD50E2DBCB90E7.taxon	description	Idiosomal ventrum. Location of ventral setae st 4 in female varies among different species of Sayanozercon gen. nov. Setae st 4 inserted on medial edge of endopodal sclerite in species: S. mariannae sp. nov., S. ergaki sp. nov. and inserted outside endopodal sclerite in species: S. adelaidae sp. nov., S. mikhaili sp. nov., S. shoricus sp. nov. Gnathosoma. Three species: Sayanozecon mariannae sp. nov., S. ergaki sp. nov., and S. mikhaili sp. nov. demonstrated sexual dimorphism in denticulation of fixed digit of chelicera — five teeth in female and six teeth in male; structure of chelicerae of two other species is difficult to examine without dissection. Internal malae demonstrated two variations of structure: bifurcate apices in S. mariannae sp. nov., S. adelaidae sp. nov., S. shoricus sp. nov. and smooth pointed apices in S. ergaki sp. nov., S. mikhaili sp. nov.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B134FFD76AAD50E2DBCB90E7.taxon	distribution	Distribution. Mites of new genus Sayanozercon are restricted in distribution to the Southern Siberia mountains in Russia. All five species of Sayanozercon inhabit middle and highlands in relict formation of mountain forest with Abies sibirica and Pinus sibirica. This ancient formation of taiga is considered as a derivative of tertiary nemoral “ Turgai flora ” by Krishtofovich (1946), widespread in the temperate zone of the Holarctic including South Siberia in Pliocene (Kuminova, 1960, Ogureeva, 1980). Two species S. mariannae and S. adelaidae are known from Khamar-Daban Ridge in Baikal Region (Buryatia and Irkutskaya Oblast). Two species distributed in West Sayan Mountains: S. ergaki and S. mikhaili Two species are known from Gornaya Shoria mountain massif (Kemerovo Region): S. mikhaili and S. shoricus. A map of the distribution of Sayanazercon in different regions of South Siberia is presented in Fig. 62. Photos of localities in different regions of South Siberia mountains are shown in Figures 63 – 70.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B134FFD76AAD50E2DBCB90E7.taxon	discussion	Comparison with related genera (adults). Based on information about genera of Zerconidae in the world fauna, it can be stated that genera with combination of characters of new genus Sayanozercon have not yet been recorded. The presence of additional latero-ventral shield was previously noted in two genera Krantzas Błaszak and Rotundozercon Ujvári. Genus Krantzas (U. S. A., Oregon) represented by one species K. mirificus Błaszak, 1981, has a shortened latero-ventral shield located between peritrematal and ventrianal shields from setae s 6 to R 6 – R 7. Two species of genus Rotundozercon have been recorded in mountains of Southeast Asia: R. shuriken Ujvári, 2011 and R. jinggangshanensis Ma & Lin, 2014. These two species represent latero-ventral shield reaching seta r 4 anteriorly and different degrees of fusion shields at posterior edge: latero-ventral shield fused with ventrianal shield at level of setae R 4 – R 5 in R. shuriken and long, fused at level of setae R 6 – R 7 in R. jinggangshanensis. Shape of epistome of Sayanozercon is somewhat similar to Prozercon - type by Ujvári (2011 b), to genera Echinozercon Błaszak and Bakeras Błaszak, but central process of epistome in designated genera lacks spines. The epistome of Sayanozercon is most similar to Blaszakiella Sikora & Skoracki. Only two species of Blaszakiella – B. mahunkai Ujvári, 2013 and B. luisiae Ujvári, 2013 (Canada, British Columbia; U. S. A., state Washington) have an epistome with a central process with group of irregularly inserted spines. The location of gland gdZ 1 anterolateral to seta Z 1 in four species of genus Sayanozercon (S. mariannae S. adelaidae, S. ergaki, S. mikhaili) is similar to representatives of the genus Blaszakiella – B. americana Sikora & Skoracki, 2008 (U. S. A., Oregon) and subgenus Zercon (Zercorientalia) Ujvári with three species: Z. (Z.) formosianus Ujvári, 2011, Z. (Z.) spinosus Ujvári, 2011, Z. (Z.) sinensis Petrova & Taskaeva, 1968 from Southeast Asia. The dorsal chaetotaxy of Sayanozercon with all setae smooth and acicular is similar to the genera Monozercon Błaszak (U. S. A., Oregon) and amphipalearctic genus Zerconella Willmann (Willmann, 1953, Błaszak, 1984, Ujvári, 2010). Special characteristics of the genus Sayanozercon includes sexual dimorphism of chelicerae denticulation. Călugăr (2004 / 2006) found that terminal part of fixed digit is bifurcated in males of Prozercon and Zercon species. This fact was supported in other genera of Zerconidae by Ujvári (2011 b). Fixed digit of male chelicera of Sayanozercon has six teeth versus female with five teeth (S. mariannae, S. ergaki, S. mikhaili, chelicerae of two other species were not dissected). Pilus dentilis is present on the fixed digit of chelicerae of Sayanozercon, but not observed in most genera of Zerconidae. Exceptions are the early derivate genera Halozercon and Baikalozercon (Marchenko, 2018, 2019, 2021, 2022). The very interesting thing is strong sexual dimorphism emphasised in ventral chaetotaxy / porotaxy in Sayanozercon. The fibre brush structure in the inguinal region differs between males and females. Moreover, presence of fibre brush medial part in males (between left and right inguinal regions, not reported in females) could be related to the lack of setae st 5 in males (anterior to inguinal region); replacement of glands gv 2 on soft cuticle at level of inguinal regions in females to ventrianal shield in males and lack of setae Zv 1 in males (gv 2 in males are placed antero-laterally to Jv 1, more or less within the area usually occupied with Zv 1. Postcoxal cuticular spines of inguinal region in genus Zercon were observed by Marquardt et al. (2024) with special study of Zercon hamaricus Kaczmarek et al. 2021. Preliminary hypothesis of Marquardt et al. (2024) is what cuticular spines can be considered as protection the depressions at the posterior edges of coxae IV against fine soil particles that could limit or even block the leg movements. The most similar organs behind to coxae IV with deep depressions wich contains numerous cuticular spines were described by Hammen (1983) in Allothyridae, named peridium. The peridium is a peculiarity previously known among Allothyridae (Holothyrida) and Asternoseiidae (Cercomegistina) – early derivative taxa of Parasitiformes (Walter, 2009; Lindquist et al. 2009). Its function is unknown. Alberty & Seeman (2004) concluded that peridium may serve to provide volatile substances, whereby the spines would increase the surface area from which these substances may be delivered. According to these authors spines are not likely to be the structures from which the secretion is extruded as Hammen (1989) suggested. According Walter (2009) the numerous integumental exocrine glands of Allothyridae probably are involved in production of a secretion that spreads over the cuticle via excavation canals. Order Holothyrida has a distribution largely confined to former Gondwanan landmasses (Travé, 1982), but family Zerconidae are common in Northern Hemisphere, occurring both in arctic latitudes and in highlands. There is no doubt that in all five known species of Sayanozercon the presence of large post-coxal poroids associated with the presence of a dense fibrous brush in the inguinal region. I suppose that inguinal glands produce a secretion and fibre brush function is to leave an odorous trace on the substrate. The presence of similar postcoxal structures with glands covered by cuticular spines in taxa that are distant both in systematic position and in type of geographical distribution would be interesting to study further.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B136FFC46AAD5763DBD9929B.taxon	description	(Figures 1 – 29) Female (Figs 1 – 6, 17 – 23, n = 10) Dorsal idiosoma (Figs 1, 17). Idiosoma pear-shaped, 540 – 575 long, 425 – 460 wide, without obvious ornamentation, divided into two shields that cover entire dorsal idiosoma. All dorsal setae smooth, pointed. Podonotal shield with 20 pairs of setae, including r 1 seta inserted in dorsal side and r 3 seta located in peritrematal shield, seta r 3 is 3 times longer than r 1. Setae s 1, z 1 and z 2 lost. Length of podonotal setae female, male and nymphs summarized in Table 2. Setae of j- series comparable length. Setae z 4 and z 5 the longest in z - series. Setae s 3 longest in s - series and among all podonotal setae. Seta r 1 shortest in r - series. Podonotal shield with three pairs of glands: gdj 2 (po 1), gdj 4 (po 2), gdz 5 (po 3) and five pairs of lyrifissures: idj 1, idj 3, idz 4, ids 4, idj 6. Location of podonotal glands: gdj 2 (po 1) on line connecting insertions of setae j 2 and z 3; gdj 4 (po 2) on line connecting insertions of setae j 4 and z 4; gdz 5 (po 3) close and anterior to line connecting insertions of setae z 5 and s 5. Opisthonotal shield with delicate horizontal lines between setae J 4 and J 5. Medial zone betetween J – J series setae with small irregular spots visible through the cuticle. Opisthonotum with 20 pairs of setae. Lengths of opisthonotal setae and longitudinal distances between insertions of setae in specific series of female, male and nymphs summarized in Table 3. Set of J - series with four pair of setae, because J 3 lost; setae J 4, J 5 shortest; setae J 5 located directly above medial posterodorsal cavities. Remaining series with a full set of setae. Z - series with longest setae Z 3, Z 4 and Z 5, extend beyond the edge of the shield. All setae of S - series extend beyond the edge of the shield, of these setae S 4, S 5 longest. Setae of R - series all long, of similar length. Opisthonotal shield with four pairs of glands and 13 pairs of lyrifissures as shown in Fig. 1: gdz 6 (Po 1) anteromedial to seta Z 1; gdZ 1 (Po 2) anterolateral to seta Z 1; gdZ 3 (Po 3) close to line connecting insertions of setae Z 3 and Z 4; gdZ 4 (Po 4) on posterior margin of shield behind insertion of seta S 5; lyrifissures: ids 6, idS 1, idz 6, idS 4, idZ 4, idJ 4, idJ 5, idJ 2, idJ 3, doubled idJ 1 and doubled idS 3. Posterodorsal cavities rounded curvings, all equal size, located at posterior margin of opisthonotal shield. Ventral idiosoma (Figs 2 – 3, 18 – 20, 22). Base of tritosternum 30 – 32 long, 25 – 27 wide; paired laciniae with three distal branches (Fig. 2). Sternal shield 68 – 70 long at midline, 75 – 85 wide at level st 2 setae; with strong reticulate ornamentation except central “ window ” with fine lines; with setae st 1 – st 3 similar in length, 15 – 20, smooth and pointed; with three pairs of lyrifissures iv 1, iv 2 and iv 3 and one pair of glands gv 1 (Figs 3, 18, 20). Epiginal shield 122 – 125 long and 110 – 115 wide with setae st 5 (20 – 22) on shield and pair of lyrifissures iv 5, with ornamentation and inner structure as shown in Fig. 3. Large endopodal sclerites between coxae III – IV with pair of setae st 4 (18 – 20) and small, ovate-oblong endopodal sclerites around posterior parts of coxae IV presented. Pair of long exopodal sclerites extends from coxae IV to coxae I, closely adjacent to peritrematal shields and bend to dorsal side anteriorly. Pair of peritrematal shields adjacent to additional latero-ventral shields anteriorly at level of coxae II and free at level of coxae III – IV. Peritrematal shield truncate at posterior margin, not fused with ventri-anal shield; with fibre brush of cuticular structure and two conspicuous rounded poroids in inguinal region (gvi and ivi) (Figs 19 – 20, 22). Peritrematal shields with pair of smooth and pointed setae r 3; with two pairs of lyrifissures ip 1, ip 2 and gland gp from each side. Peritremes short, 50 – 55. Latero-ventral shield weakly reticulated, extending vertically from seta r 3 to R 6 (Figs 18, 20). Adgenital sclerites presented each with 4 – 5 glands openings gv 2. Ventrianal shield 245 – 250 long, 330 – 345 wide at level seta Zv 2, with 21 smooth, pointed setae; with transversal reticulation from anterior margin to level setae Jv 3. Anterior margin of ventrianal shield with two shortest pairs of setae Jv 1 and Zv 1 (12 – 13). Other setae in J - series: Jv 2 (17 – 20), Jv 3 (30 – 37), Jv 4 (38 – 40), Jv 5 (65 – 75); other setae in Z - series: Zv 2 (12 – 13), Zv 3 (18 – 20), Zv 4 (20 – 22); para-anal setae 50 – 55, post-anal 45 – 50 long. Pair of glands gv 3 located at level posterior margin of anal opening. Five pairs of ventrianal lyrifissures present: ivo 1 – ivo 4 and ivp. Anal opening with two pairs of lyrifissures on each valve. Cribrum presented posteriorly of post-anal setae. Gnathosoma (Figs 4 – 6, 21, 23). Movable digit of chelicera 55 – 60 long, with three teeth in addition to apical hook; fixed digit the same length, with five teeth including offset distal tooth (gabelzhan), followed by four teeth in masticatory surface in addition to apical hook and leaf-shaped pilus dentilis, apical sensorial depression presents (Fig. 4). Chelicera with long dorsal seta, lateral (antiaxial) and dorsal lyrifissures; with smooth arthrodial corona and suboval area (“ window ”) of thin cuticle on paraxial side. Epistome with irregularly serrated lateral edges, medial ridge and serrated middle process with median row of small spines; lateral margins of epistome with clearly visible structures, apparently serving as limiters for the cheliceral shafts (Figs 5, 23). Corniculi horn-like, internal malae extending beyond corniculi, with fimbriate lateral margins and bifurcate apices. Deutosternal groove with seven transverse denticulate rows, each row with 6 – 13 small denticles. Hypostome with four pairs of setae, setae h 1 – h 3 smooth, h 1 (40 – 42) the longest, seta h 2 (23 – 25) shorter than h 3 (28 – 30), pc (30 – 32) serrated (Figs 6, 21). Palpal chaetotaxy 2 – 5 – 6 – 12 – 15 with five free segments; pilose setae on palp trochanter v 1 and v 2; on palp femur d 3, on palp genu al 2; palp tarsal claw two-tined. Legs. Chaetotaxy of legs I – IV: coxae 2, 2, 2, 1; trochanters 6 (1 1 / 3 1), 5 (1 1 / 3 0), 5 (1 1 / 3 0), 5 (1 1 / 3 0); femora 13 (2 5 / 4 2), 11 (2 5 / 3 1), 6 (1 4 / 1 0), 6 (1 4 / 1 0); genua 13 (2 6 / 3 2), 11 (2 5 / 2 2), 10 (2 4 / 2 2), 10 (2 5 / 2 1); tibiae 14 (2 6 / 4 2), 10 (2 4 / 2 2), 9 (2 3 / 2 2), 9 (2 3 / 2 2); tarsi I – 49 (6 29 / 9 5), II – IV 18 (3 7 / 5 3). Chaetotaxy of I – IV legs is typical for Zerconidae (Halašková, 1969; Sikora, 2014). Pretarsus of legs II – IV with ambulacral stalk, tarsi I with sessile claws. Coxae I with dorsal incision, coxae II with antero-dorsal spine. Male. (Figs 7 – 10, 24 – 29, n = 10). Dorsal idiosoma. (Fig. 7). Dorsal idiosoma pear-shaped, 450 – 485 long, 340 – 355 wide. Ornamentation, chaetotaxy, adenotaxy and poroidotaxy of dorsal shields as in female. Lengths of podonotal setae of males summarized in Table 2. Lengths of opisthonotal setae and longitudinal distances between insertions of setae in specific series of male summarized in Table 3. Ventral idiosoma. (Figs 8, 24, 26 – 29). Tritosterum form as in female. Sternal shield fused with genital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2. Sternigenital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2, 150 – 155 long with four pairs of setae st 1 – st 4 (15 – 18), three pairs of lyrifissures iv 1, iv 2 and iv 5, one pair of glands gv 1 and genital opening opposite coxae III. Eugenital setae presented as shown in SEM photo (Fig. 26). Peritrematal shields each with short peritrema, with smooth and pointed seta r 3, with lyrifissures ip 1, ip 2 and glands gp (Figs 24, 26, 28 – 29). Peritrematal shields connected posteriorly to each other by fibre brush of cuticular structure with two pairs of rounded formations hollow inside (inguinal poroids gvi and ivi) (Figs 26 – 29). Latero-ventral shields shaped as in female, with reticulate ornamentation (Fig. 24). Ventrianal shield with weakly transversal reticulation, 200 – 218 long and 280 – 290 wide; with 19 smooth and pointed setae, setae Zv 1 lost; with five pairs of lyrifissures ivo 1 – ivo 4, ivp and pair of glands gv 3. Length of ventrianal setae: Jv 1 (12 – 13), Jv 2 (16 – 18), Jv 3 (25 – 30), Jv 4 (27 – 40), Jv 5 (65 – 75), Zv 2 – Zv 4 (16 – 18), para-anal setae 40 - 50, post-anal 38 – 42 long. Multiple glands gv 2 with 4 – 5 openings located on anterior margin of ventrianal shield. Anal opening with two pairs of lyrifissures on each valve. Cribrum presented posteriorly of post-anal seta. Gnathosoma (Figs 9 – 10, 25). Movable digit of chelicera 42 – 45 long, with three teeth in addition to apical hook, fixed digit the same length, with six teeth, including offset lateral-distal tooth (gabelzhan), followed by five teeth in masticatory surface in addition to apical hook and leaf-shaped pilus dentilis, apical sensorial depression presents (Figs 9, 25). Male chelicera with dorsal seta, lyrifissures and arthrodial corona as in female. Epistome (Fig. 10), corniculi, internal malae and palpal structures as in female. Legs. Chaetotaxy and morphology of legs as in female. Deutonymph (Figs 11 – 13, n = 8). Dorsal idiosoma. Dorsal idiosoma pear-shaped, 445 – 475 long, 360 – 375 wide, divided into two shields (Fig. 11). All dorsal setae smooth and pointed. Podonotal shield with 20 pairs of setae, setae s 1 and z 2 absent, three pairs of glands gdj 2, gdj 4, and gdz 5 located as in adults; without reticulation. Opisthonotal shield weakly ornamentated, with 20 pairs of setae, pair of setae J 3 absent, with four pairs of glands: gdz 6, gdZ 1, gdZ 3 and gdZ 4. Most dorsal lyrifissures not visible. Lengths of podonotal setae of deutonymphs and lengths of opisthonotal setae and longitudinal distances between insertions of setae in specific series summarized in Table 3. Ventral idiosoma. Sternal shield with smooth, pointed setae st 1 – st 5, where s t 5 inserted on soft cuticle, with two pairs of visible lyrifissures iv 1 and iv 2 (Fig. 12). Sternal setae are equal length: st 1 – st 3 23 – 25, st 4 – st 5 (12 – 15). Metapodal platelets large, triangular shapes, free from ventrianal shield. Peritremes long 165 – 175, reaching to mid coxae I. Narrow strip of sclerotised cuticle adjacent laterally along of peritrema; with gland gp on it. Marginal setae r 3 located on soft cuticle. Pair of small rounded formations (inguinal poroids gvi and ivi) and glands gv 2 with three openings located behind coxa from each side. Ventrianal shield with transversal reticulation; wider than long (180 – 192 x 270 – 275), with 17 smooth pointed setae; with pair of glands gv 3 and cribrum. Opisthogastral setae Jv 1 and Zv 1 located on soft cuticle, anteriorly of ventrianal shield. Length of opisthogastral setae: Jv 1 – Jv 2 (10 – 15), Jv 3 – Jv 4 (25 – 27), Jv 5 (63 – 65), Zv 1 and Zv 4 (7 – 10), Zv 3 (15 - 17). Para-anal setae (37 – 39), post-anal (50 – 55) long. Gnathosoma (Fig. 13). Denticulation of chelicera as in female. Epistome with irregularly serrated lateral edges serrated middle process with median row of small spines and three branches in top; lateral margins of epistome with clearly visible structures as in adults. Legs. Chaetotaxy and morphology of legs as in female. Protonymph (Figs 14 – 16, n = 1). Dorsal idiosoma (Fig. 14). Dorsal idiosoma suboval form, 387 long and 295 wide, without ornamentation of podonotal and pygidial shields. All dorsal setae smooth and pointed. Podonotal shield with 15 pairs of setae: six pairs of setae in j - row (j 1 – j 6), z - row with three pairs of setae (z 3 – z 5), s - row with four pairs of setae (s 3 – s 6) and two pairs of setae in r - row (r 3, r 5), with one pair of visible glands gdz 5. Lengths of podonotal setae of protonymphs summarized in Table 2. Lengths of opisthonotal setae and longitudinal distances between insertions of setae in specific series of protonymphs, summarized in Table 3. Opisthonotal region presented by one large pygidial shield with 14 pairs of setae: J - row with four pairs of setae (J 1 – J 2, J 4 – J 5), pair of J 3 setae absent, Z - row with five pairs (Z 1 – Z 5), S - row with four pairs (S 2 – S 5), R - row with one pair of setae R 1 and two pairs of visible glands gdZ 3 and gdZ 4. Posterodorsal cavities presented. Ventral idiosoma (Fig. 15). Tritosternum as in adults. All ventral setae simple form. Sternal shield with three pairs of setae St 1 – St 3 equal length (17 – 20), seta St 5 minute (5 – 6). Peritrematal shields not distinct. Peritremes very short (35), with pairs of thin ducts leading from stigmata. Adgenital pores and pair of glands gv 2 not visible. Opisthogastric area with one pair of Jv 1 setae (12) inserted in soft cuticle. Ventrianal shield with transversal reticulation, with nine setae: Jv 2 (23), Jv 5 (63), Zv 2 (12), para-anal setae (27) and post-anal seta (43); pair of glands gv 3. Cribrum present posteriorly to post-anal seta. Anus with two anal lyrifissures on each valve. Gnathosoma (Fig. 16). Corniculi, internal malae as in adult; epistome with irregularly serrated lateral edges, serrated middle process with median row of small spines and three branches in top. Lateral structures of epistome presented. Legs. Chaetotaxy of legs I – IV: coxae 2, 2, 2, 1; trochanters 4, 4, 4, 4; femora 10 (2 4 / 2 2), 8 (1 4 / 2 1), 5 (1 3 / 1 0), 4 (1 3 / 0 0); genua 8 (1 4 / 2 1), 6 (1 4 / 0 1), 6 (1 4 / 0 1), 5 (1 4 / 0 0); tibiae 8 (1 4 / 2 1), 7 (1 3 / 2 1), 7 (1 3 / 2 1), 7 (1 3 / 2 1); tarsi II – IV 17 (3 7 / 4 3). Pretarsus of legs II – IV with ambulacral stalk, tarsi I with sessile claws. Coxae I with dorsal incision, coxae II with antero-dorsal spine. Protonymphal chaetotaxy of legs I – IV is typical for Zerconidae (Halašková, 1969). Larvae not found.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B136FFC46AAD5763DBD9929B.taxon	materials_examined	Material examined. Holotype female, Russia, Baikal Region, BURYATIA Republic, Kabanskii district, environs of Tankhoi village, foot of Khamar-Daban Ridge, forest in valley of Kurkavka river, 51 ° 33 ’ N, 105 ° 09 ’ E, 470 m a. s. l., in litter, 9. VIII 2014, leg. I. I. Marchenko. Paratypes: 10 females, 8 males, same data as holotype; 4 females, same geographical data, 51 ° 35 ’ N, 104 ° 22 ’ E, 500 m a. s. l., forest in valley of Osinovka river, in litter, 9. VIII 2014, leg. I. I. Marchenko; 4 females, same geographical data as holotype, 51 ° 47 ’ N, 105 ° 24 ’ E, 500 m a. s. l., taiga along estuary of Pereemnaya river, in litter, 10. VIII 2014, leg. I. I. Marchenko; IRKUTSKAYA OBLAST: 3 females, 2 males, same geographical data, environs of Vydrino village, foot of Khamar-Daban Ridge, Monomakh Mt., 51 ° 23 ’ N, 104 ° 38 ’ E, 400 m a. s. l., mixed forest, in litter, 23. VI 2021, leg. I. I. Marchenko; 7 females, 7 males, same geographical data, environs of Vydrino village, 51 ° 22 ’ N, 104 ° 39 ’ E, 500 m a. s. l., taiga Abies sibirica – Pinus sibirica along Snezhnaya river, road to Taltsinsky Peak, in litter, 23 – 28. VI 2021, leg. I. I. Marchenko; 3 females, 4 males, same geographical data, environs of Vydrino village, 51 ° 22 ’ N, 104 ° 39 ’ E, 700 m a. s. l., taiga Abies sibirica – Pinus sibirica along Snezhnaya river, road to Taltsinsky Peak, in litter, 26. VI 2021, leg. I. I. Marchenko. Other material: 1 female, 2 males, 5 deutonymphs, data as holotype; 1 female, 2 deutonymphs, 1 protonymph, Baikal Region, BURYATIA Republic, Kabanskii district, environs of Tankhoi village, foot of Khamar-Daban Ridge, 51 ° 47 ’ N, 105 ° 24 ’ E, 51 °, 500 m a. s. l., taiga along estuary of Pereemnaya river, in litter, 10. VIII 2014, leg. I. I. Marchenko; 1 deutonymph, same geographical region, environs of Vydrino village 22 ’ N, 104 ° 39 ’ E, 500 m a. s. l., taiga Abies sibirica – Pinus sibirica along Snezhnaya river, road to Taltsinsky Peak, in litter, 23. VI 2021, leg. I. I. Marchenko.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B136FFC46AAD5763DBD9929B.taxon	etymology	Etymology. The new species S. mariannae is named in honor of my acarologist teacher, author of numerous species and publications on Mesostigmata mites of Siberia – Marianna S. Davydova (1918 – 1994).	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B136FFC46AAD5763DBD9929B.taxon	discussion	Remarks. The distinguishing characters of adults of Sayanozercon mariannae sp. nov. are: large size of idiosoma; pair of setae s 1 is lost on podonotal shield; opisthonotal shield with four pairs of setae in J - series, among which pair of J 3 setae is lost; setae in J - series comparatively short, among which setae J 4 and J 5 the shortest; setae Z 3, S 2, S 3 and S 4 long, extend beyond the edge of opisthonotal shield. Podonotal gland gdz 5 (po 3) located close and anterior to line connecting insertions of setae z 5 and s 5; Location of opisthonotal glands: gdz 6 (Po 1) anteromedial to seta Z 1; gdZ 1 (Po 2) anterolateral to seta Z 1. Gnathosoma with internal malae with bifurcate apices; fixed digit of chelicera with sexual dimorphism – five teeth in female and six teeth in male.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B125FFC06AAD51F5DC9997CB.taxon	description	(Figures 30 – 36) Female (Figs 30 – 33, n = 4) Dorsal idiosoma (Fig. 30). Idiosoma pear-shaped, 475 – 500 long, 330 – 340 wide, without obvious ornamentation, divided into two shields that cover entire dorsal idiosoma. All dorsal setae smooth and pointed. Podonotal shield with 21 pairs of setae, including r 1 located in podonotal shield and r 3 located in peritrematal shield; seta r 3 is 4 times longer than r 1. Setae z 1 and z 2 lost. Length of podonotal setae female and male summarized in Table 4. Setae of j- series j 1 – j 4 comparable length, setae j 5 and j 6 the shortest. Setae z 4 the longest in z - series. Setae s 1 shortest and s 3 longest in s - series. Seta r 1 shortest in r - series. Podonotal shield with three pairs of glands: gdj 2 (po 1), gdj 4 (po 2), gdz 5 (po 3) and five pairs of lyrifissures: idj 1, idj 3, idz 4, ids 4, idj 6. Location of podonotal glands: gdj 2 (po 1) posterior to insertion of seta s 1, close to line connecting insertions of setae j 2 and z 3; gdj 4 (po 2) on line connecting insertions of setae j 4 and z 4; gdz 5 (po 3) on line connecting insertions of setae s 4 and s 5. Opisthonotal shield with delicate horizontal lines between setae J 2 and J 5, with 21 pairs of setae. Lengths of opisthonotal setae and longitudinal distances between insertions of setae in specific series of female and male summarized in Table 4. J - row with five pairs of short setae J 1 – J 5, among which J 4, J 5 shortest; setae J 5 located directly above medial posterodorsal cavities. Remaining series also with a full set of setae. Z - series with longest setae Z 4 and Z 5 extend beyond the edge of the shield and short setae Z 1 – Z 3 comporable length. S - series with longest setae S 5 extend beyond the edge of the shield, setae S 2 – S 4 short, comparable length. Setae of R - series all long, similar length. Opisthonotal shield with four pairs of glands and 13 pairs of lyrifissures located as shown in Fig. 30: gdz 6 (Po 1) anteromedial to seta Z 1; gdZ 1 (Po 2) anterolateral to seta Z 1; gdZ 3 (Po 3) close to line connecting insertions of setae Z 3 and Z 4; gdZ 4 (Po 4) on posterior margin of shield behind insertion of seta S 5; lyrifissures: ids 6, idS 1, idz 6, idS 4, idZ 4, idJ 4, idJ 5, idJ 2, idJ 3, doubled idJ 1 and doubled idS 3. Posterodorsal cavities rounded curvings, all equal size, located at posterior margin of opisthonotal shield. Ventral idiosoma (Fig. 31). Base of tritosternum 30 – 32 long, 20 – 23 wide; paired laciniae with three distal branches. Sternal shield 68 – 70 long at midline, 67 – 70 wide at level st 2 setae; with reticulate ornamentation, with setae st 1 – st 2 similar in length, 17 – 19, st 3 15 – 16, all smooth and pointed; with three pairs of lyrifissures iv 1, iv 2 and iv 3 and one pair of glands gv 1. Epiginal shield 105 – 107 long and 83 – 85 wide with setae st 5 (17 – 20) on shield and pair of lyrifissures iv 5. Pair of setae st 4 (17 – 19) located outside large endopodal sclerites between coxae III – IV; small ovate-oblong endopodal sclerites behind posterior parts of coxae IV presented. Pair of long exopodal sclerites extends from coxae IV to coxae I, closely adjacent to peritrematal shields and bend to dorsal side anteriorly. Pair of peritrematal shields adjacent to additional latero-ventral shields anteriorly and free at level of coxae III – IV. Peritrematal shields with smooth and pointed seta r 3; two lyrifissures ip 1, ip 2 and gland gp from each side. Peritrematal shields truncate at posterior margin; with fibre brush of cuticular structure and two rounded formations in inguinal region (poroids gvi and ivi) from each side. Peritremes are very short, 30 – 32. Latero-ventral shields weakly reticulated extend from seta r 3 to R 6. Adgenital sclerites presented each with 4 – 5 gland openings gv 2. Ventrianal shield reticulated, 210 – 215 long, 275 – 280 wide at level of seta Zv 2, with 21 smooth, pointed setae. Anterior margin of ventrianal shield with two shortest pairs of setae Jv 1 and Zv 1 (10 – 12). Other setae in J - series: Jv 2 (15 – 17), Jv 3 (20 – 23), Jv 4 (30 – 32), Jv 5 (40 – 43); other setae in Z - series: Zv 2 (10 – 12), Zv 3 (20 – 22), Zv 4 (15 – 17); para-anal setae 43 – 45, post-anal 30 – 32 long. Pair of glands gv 3, five pairs of ventrianal lyrifissures ivo 1 – ivo 4 and ivp presented. Anal opening with two pairs of lyrifissures on each valve. Cribrum presented posteriorly of post-anal setae. Gnathosoma (Figs 32 – 33). Movable digit of chelicera 52 – 55 long, with three teeth in addition to apical hook; fixed digit the same length, with five teeth, including offset distal tooth (gabelzhan), four teeth in masticatory surface in addition to apical hook; leaf-shaped pilus dentilis presented (Fig. 32). Chelicera with dorsal seta, lateral (antiaxial) and dorsal lyrifissures; with smooth arthrodial corona. Epistome with irregularly serrated lateral edges, medial ridge and irregularly serrated middle process with median row of small spines (Fig. 33). Corniculi horn-like, internal malae extending beyond corniculi, with fimbriate lateral margins and bifurcate apices. Hypostome with four pairs of setae, setae h 1 – h 3 smooth, h 1 (25 – 27) the longest, seta h 2 (12 – 15) shorter than h 3 (17 – 20), setae pc serrated (30 – 32). Palpal chaetotaxy typical for genus Sayanozercon. Legs. Chaetotaxy of I – IV legs is typical for Zerconidae. Pretarsus of legs II – IV with ambulacral stalk, tarsi I with sessile claws. Coxae I with dorsal incision, coxae II with antero-dorsal spine. Male. (Figs 34 – 36, n = 2). Dorsal idiosoma. (Fig. 34). Dorsal idiosoma elongated oval in shape, 415 – 430 long, 250 – 265 wide. Ornamentation, chaetotaxy, adenotaxy and poroidotaxy of dorsal shields as in female. Lengths of podonotal, opisthonotal setae and longitudinal distances between insertions of setae in opisthonotal series of male summarized in Table 3. Ventral idiosoma. (Fig. 35). Tritosterum form as in female. Sternal shield fused with genital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2. Sternigenital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2, 137 – 150 long with four pairs of setae st 1 – st 4 (10 – 15), three pairs of lyrifissures iv 1, iv 2 and iv 5, one pair of glands gv 1 and genital opening opposite coxae III, eugenital setae not visible under light microscopy. Peritrematal shields each with short peritrema (25), smooth and pointed setae r 3, with two pairs of lyrifissures ip 1, ip 2 and pair of glands gp; connected posteriorly to each other by fibre brush of cuticular structure. Inguinal region of peritrematal shields with two pairs of rounded formations hollow inside (inguinal poroids gvi and ivi). Latero-ventral shields shaped as in female, with weak longitudinal reticulation. Ventrianal shield with weak cellular reticulation, 182 – 185 long and 215 – 225 wide; with 19 smooth and pointed setae, setae Zv 1 lost; with five pairs of lyrifissures ivo 1 – ivo 4, ivp and pair of glands gv 3. Length of ventrianal setae: Jv 1 (10 – 12), Jv 2 (10 – 15), Jv 3 (25 – 30), Jv 4 (20 – 25), Jv 5 (20 – 33), Zv 2 – Zv 4 (10 – 12), para-anal setae 32 – 34, post-anal 30 – 32 long. Multiple glands gv 2 with 4 openings located on anterior margin of ventrianal shield. Anal opening with two pairs of lyrifissures on each valve. Cribrum presented posteriorly of post-anal seta. Gnathosoma (Fig. 36). Male movable digit of chelicera 40 – 42 long, fixed digit the same length, denticulation is not clearly visible. Dorsal seta, lyrifissures and arthrodial corona are not clearly distinguishable. Epistome (Fig. 36), corniculi, internal malae and palpal structures as in female. Legs. Chaetotaxy and morphology of legs as in female. Juveniles not found.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B125FFC06AAD51F5DC9997CB.taxon	materials_examined	Material examined. Holotype female, Russia, Baikal region, BURYATIA Republic, Kabanskii district, environs of Tankhoi village, Khamar-Daban Ridge, alpine meadow with tall grasses, 51 ° 33 ’ N, 105 ° 09 ’ E, 1100 m a. s. l., in litter, 13. VIII 2014, coll. L. V. Petrozhitskaya. Paratypes: 1 male, same data as holotype; 1 male, same geographical data, 51 ° 33 ’ N, 105 ° 09 ’ E, 470 m a. s. l., taiga along estuary of Pereemnaya river, in litter, 10. VIII 2014, leg. I. I. Marchenko; 3 females, same geographical data, 51 ° 33 ’ N, 105 ° 09 ’ E, 700 m a. s. l., taiga with Abies sibirica – Pinus sibirica, in litter, 14. VIII 2014, coll. L. V. Petrozhitskaya.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B125FFC06AAD51F5DC9997CB.taxon	etymology	Etymology. The new species S. adelaidae is named in honor of prominent acarologist – Adelaida D. Petrova (Nikitina) (1932 – 2011), author of numerous Mesostigmata genera and species.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B125FFC06AAD51F5DC9997CB.taxon	discussion	Remarks. The distinguishing characters of adults of Sayanozercon adelaidae sp. nov. are: mid-size of idiosoma; pair of setae s 1 is present on podonotal shield; opisthonotal shield with five pairs of short setae in J - series; seta Z 3 short, setae S 2, S 3 and S 4 are also short, do not extend beyond edge of shield. Podonotal gland gdz 5 (po 3) located on line connecting insertions of setae s 4 and s 5. Location of opisthonotal glands: gdz 6 (Po 1) anteromedial to seta Z 1; gdZ 1 (Po 2) anterolateral to seta Z 1. Gnathosoma with internal malae with bifurcate apices.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B120FFCE6AAD5399DB7C91C7.taxon	description	(Figures 37 – 45) Female (Figs 37 – 41, n = 10) Dorsal idiosoma (Fig. 37). Idiosoma rounded-oval shape, 560 – 575 long, 460 – 485 wide, without obvious ornamentation, divided into two shields that cover entire dorsal idiosoma. All dorsal setae smooth, pointed. Podonotal shield with 20 pairs of setae, including r 1 located in podonotal shield and r 3 located in peritrematal shield; seta r 3 longer than r 1 (3.3 – 3.6 times). Setae s 1, z 1 and z 2 lost. Length of podonotal setae and opisthonotal setae and longitudinal distances between insertions of opisthonotal setae in specific series female and male summarized in Table 5. Setae j 1 longest in j- series, other similar length. Setae z 4 longest in z - series. Setae s 3 longest in s - series and among all podonotal setae. Seta r 1 shortest in r - series and among all podonotal setae. Podonotal shield with three pairs of glands: gdj 2 (po 1), gdj 4 (po 2), gdz 5 (po 3) and five pairs of lyrifissures: idj 1, idj 3, idz 4, ids 4, idj 6. Location of podonotal glands: gdj 2 (po 1) close to line connecting insertions of setae j 2 and z 3; gdj 4 (po 2) close to line connecting insertions of setae j 4 and z 4; gdz 5 (po 3) close and anterior to line connecting insertions of setae z 5 and s 5. Opisthonotal shield with delicate reticulation. Medial zone betetween J – J series setae with small irregular spots visible through the cuticle. Opisthonotum with 20 pairs of setae. J - series with four pairs of setae, among which J 4 longest, extend beyond the edge of the shield; setae J 5 lost. Remaining series with full set of setae. Z - series with longest setae Z 3, Z 4 and Z 5, extend beyond the edge of the shield. All setae of S - series extend beyond the edge of the shield, of these setae S 4, S 5 longest. Setae of R - series all long. Opisthonotal shield with four pairs of glands and 13 pairs of lyrifissures located as shown in Fig. 37: gdz 6 (Po 1) anteromedial to seta Z 1; gdZ 1 (Po 2) anterolateral to seta Z 1; gdZ 3 (Po 3) close to line connecting insertions of setae Z 3 and Z 4; gdZ 4 (Po 4) on posterior margin of shield behind insertion of seta S 5; lyrifissures: ids 6, idS 1, idz 6, idS 4, idZ 4, idJ 4, idJ 5, idJ 2, idJ 3, doubled idJ 1 and doubled idS 3. Posterodorsal cavities rounded curvings, all similar size, located at posterior margin of opisthonotal shield. Ventral idiosoma (Fig. 38). Base of tritosternum 35 – 37 long, 20 – 25 wide; paired laciniae with three distal branches. Sternal shield 68 – 70 long at midline, 75 – 80 wide at level st 2 setae; with fine reticulation and “ window ” with fine granular structure between st 2 – st 3 setae; with setae st 1 – st 3 similar in length, 17 – 20, smooth and pointed; with three pairs of lyrifissures iv 1, iv 2 and iv 3 and one pair of glands gv 1. Epiginal shield 125 – 130 long and 105 – 113 wide with setae st 5 (22 – 25) on shield and pair of lyrifissures iv 5. Large endopodal sclerites between coxae III – IV with pair of setae st 4 (18 – 20) and small, ovate-oblong endopodal sclerites around posterior parts of coxae IV presented. Pair of long exopodal sclerites extends from coxae IV to coxae I, closely adjacent to peritrematal shields and bend to dorsal side anteriorly. Pair of peritrematal shields adjacent to additional latero-ventral shields anteriorly and free at level coxae III – IV. Peritrematal shield truncate at posterior margin, not fused with ventrianal shield; with fibre brush of cuticular structure and with two rounded formations in inguinal region (gvi and ivi) from each side. Peritrematal shields with smooth, pointed setae r 3; with lyrifissures ip 1, ip 2 and gland gp from each side. Peritremes short, 52 – 55. Latero-ventral shield weakly reticulated, extends from seta r 3 to R 6. Adgenital sclerites presented, each with 4 – 5 glands openings gv 2. Ventrianal shield 245 – 250 long, 330 – 345 wide at level seta Zv 2, with 21 smooth, pointed setae; with transversal reticulation from anterior margin to level setae Jv 3. and with a narrow strip of darker colored cuticle about 35 µm wide. Anterior margin of ventrianal shield with two shortest pairs of setae Jv 1 and Zv 1 (10 – 12). Other setae in J - series: Jv 2 (17 – 20), Jv 3 (32 – 35), Jv 4 (50 – 52), Jv 5 (75 - 80); other setae in Z - series: Zv 2 (20 – 22), Zv 3 (27 – 30), Zv 4 (25 – 27); para-anal setae 55 - 63, post-anal 43 – 50 long. Pair of glands gv 3 usually located at level of posterior edge of the anus. Five pairs of ventrianal lyrifissures present: ivo 1 – ivo 4 and ivp. Anal opening with two pairs of lyrifissures on each valve. Cribrum presented posteriorly of post-anal setae. Gnathosoma (Figs 39 – 41). Movable digit of chelicera 55 – 60 long, with three teeth in addition to apical hook; fixed digit the same length, with five teeth, including offset distal tooth (gabelzhan) and four teeth in masticatory surface in addition to apical hook; leaf-shaped pilus dentilis and apical sensorial depression presented (Fig. 39). Chelicera with long dorsal seta, lateral (antiaxial) and dorsal lyrifissures; with smooth arthrodial corona and suboval area (“ window ”) of thin cuticle on paraxial side. Epistome with irregularly serrated lateral edges, medial ridge and serrated middle process with median row of small spines (Fig. 40). Corniculi horn-like, internal malae extending beyond corniculi, with fimbriate lateral margins and smooth pointed apices (Fig. 41). Deutosternal groove with seven transverse denticulate rows. Hypostome with four pairs of setae, setae h 1 – h 3 smooth, h 1 (40 – 42) the longest, seta h 2 (17 – 23) shorter than h 3 (25 – 32), pc (30 – 32) serrated. Palpal chaetotaxy typical for genus Sayanozercon. Legs. Chaetotaxy of I – IV legs is typical for Zerconidae. Pretarsus of legs II – IV with ambulacral stalk, tarsi I with sessile claws. Coxae I with dorsal incision, coxae II with antero-dorsal spine. Male. (Figs 42 – 45, n = 9). Dorsal idiosoma. (Fig. 42). Dorsal idiosoma pear-shaped, 475 – 485 long, 370 – 375 wide. Ornamentation, adenotaxy and poroidotaxy of dorsal shields as in female. Podonotal chaetotaxy of male as in female. Length of opisthonotal setae in male has sexual dimorphism in J - series, setae J 3 and J 4 shortest vs female in which these setae are the longest. Lengths of podonotal, opisthonotal setae and longitudinal distances between insertions of setae in opisthonotal series of male summarized in Table 5. Ventral idiosoma. (Fig. 43). Tritosterum form as in female. Sternal shield fused with genital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2. Sternigenital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2, 160 – 165 long with four pairs of setae st 1 – st 4 (15 – 18), three pairs of lyrifissures iv 1, iv 2 and iv 5, one pair of glands gv 1 and genital opening opposite coxae III, eugenital setae not visible under light microscopy. Peritrematal shields with short peritrema, smooth, pointed seta r 3, two lyrifissures ip 1, ip 2 and gland gp from each side. Peritrematal shields connected posteriorly to each other by fibre brush of cuticular structure; with two pairs of rounded formations hollow inside (inguinal poroids gvi and ivi) on posterior margins. Latero-ventral shields shaped as in female, with longitudinal reticulation. Ventrianal shield with weak transversal reticulation, 210 – 215 long and 285 – 290 wide; with 19 smooth and pointed setae, setae a Zv 1 absent; with five pairs of lyrifissures ivo 1 – ivo 4, ivp and pair of glands gv 3. Length of ventrianal setae: Jv 1 (10 – 13), Jv 2 (15 – 18), Jv 3 (25 – 30), Jv 4 (30 – 35), Jv 5 (63 – 70), Zv 2 – Zv 4 (15 – 20), para-anal setae 40 - 50, post-anal 37 – 40 long. Multiple glands gv 2 with 4 – 5 openings located on anterior margin of ventrianal shield. Anal opening with two pairs of lyrifissures on each valve. Cribrum presented posteriorly of post-anal seta. Gnathosoma (Figs 44 – 45). Movable digit of chelicera 42 – 45 long, with three teeth in addition to apical hook, fixed digit the same length, with offset lateral-distal tooth (gabelzhan), followed by five teeth in masticatory surface in addition to apical hook; leaf-shaped pilus dentilis and apical sensorial depression presented (Fig. 44). Denticulation of male fixed digit has sexual dimorphism – five teeth in masticatory surface vs female with four teeth in masticatory surface. Male chelicera with dorsal seta, lyrifissures and arthrodial corona as in female. Epistome (Fig. 45), corniculi, internal malae and palpal structures as in female. Legs. Chaetotaxy and morphology of legs as in female. Juveniles not found.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B120FFCE6AAD5399DB7C91C7.taxon	materials_examined	Material examined. Holotype female, Russia, KHAKASSIA, West Sayan Mt., 40 km from Abaza city along Korasibo river, 52 ° 35 ’ N, 90 ° 08 ’ E, 700 m a. s. l., taiga with Abies sibirica – Picea obovata – Pinus sibirica, in litter, 25. VI 2013, leg. I. I. Marchenko. Paratypes: 2 females, 2 males, same data as holotype; KRASNOYARSKII KRAI, 1 female, 2 males, West Sayan Mt., Ergaki Ridge, pass Olenya Rechka, 52 ° 48 ’ N, 93 ° 14 ’ E, 1479 m a. s. l., taiga with Abies sibirica – Pinus sibirica, in moss, 20. VII 2018, leg. I. I. Marchenko; 1 female, West Sayan Mt., Ergaki Ridge, 52 ° 49 ’ N, 93 ° 17 ’ E, 1400 m a. s. l., road to Visit Center, taiga with Abies sibirica – Pinus sibirica, in moss, 4. VI 2024, leg. I. I. Marchenko; 7 females, 6 males, West Sayan Mt., Ergaki Ridge, 52 ° 46 ’ N, 93 ° 21 ’ E, 1117 – 1250 m a. s. l., taiga along Tushkanchik river, Abies sibirica – Pinus sibirica, in moss, leg. I. I. Marchenko; TUVA, 3 females, 1 male, Mongun Taiga Ridge, near Khindigtik-Khol lake, 50 ° 21 ’ N, 89 ° 49 ’ E, 2300 m a. s. l., alpine tundra, in moss, 3. VII 2013, coll. A. Kostyunin.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B120FFCE6AAD5399DB7C91C7.taxon	etymology	Etymology. New species S. ergaki is named after Ergaki Ridge in Western Sayan Mountains in southern Siberia of Russia, where most of the material of this species was found.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B120FFCE6AAD5399DB7C91C7.taxon	discussion	Remarks. Distinguishing characters of adults of Sayanozercon ergaki sp. nov. are: large size of idiosoma; setae s 1 lost on podonotal shield; opisthonotal shield with four pairs of setae in J - series, among which pair of J 5 setae not developed. Sayanozercon ergaki sp. nov. with sexual dimorpism of chaetotaxy in J - series: in female seta J 1 shortest, and setae J 3 and J 4 longest; seta J 3 extends beyond base of J 4, seta J 4 extends beyond the edge of opisthonotal shield; in male setae J 3, J 4 shortest; pair of J 4 setae does not approach posterodorsal cavities. Both sexes with longest setae Z 3, Z 4, Z 5 in Z - series; Z 3 and Z 4 extend beyond the edge of shield; setae in S - series all long extend beyond edge of opisthonotal shield. Gland gdz 5 (po 3) located close and anterior to line connecting insertions of setae z 5 and s 5. Location of opisthonotal glands: gdz 6 (Po 1) anteromedial to seta Z 1; gdZ 1 (Po 2) anterolateral to seta Z 1. Gnathosoma with internal malae with smooth pointed apices; fixed digit of chelicera with sexual dimorphism – five teeth in female and six teeth in male.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B12EFFF46AAD5399D98291E3.taxon	description	(Figures 46 – 54) Female (Figs 46 – 50, n = 10) Dorsal idiosoma (Fig. 46). Idiosoma rounded-oval shape, 545 – 565 long, 400 – 425 wide, without obvious ornamentation, divided into two shields that cover entire dorsal idiosoma. All dorsal setae smooth, pointed. Podonotal shield with 21 pairs of setae, including r 1 located in podonotal shield and r 3 located in peritrematal shield; seta r 3 is 4 times longer than r 1. Setae z 1 and z 2 lost. Seta s 1 presented. Length of podonotal setae and opisthonotal setae and longitudinal distances between insertions of opisthonotal setae in specific series female and male summarized in Table 6. Setae j 6 shortest in j- series, setae z 4 longest in z - series, setae s 1 shortest and setae s 3 longest in s - series and among all podonotal setae. Seta r 1 shortest in r - series and among all podonotal setae. Podonotal shield with three pairs of glands: gdj 2 (po 1), gdj 4 (po 2), gdz 5 (po 3). Location of podonotal glands: gdj 2 (po 1) close to line connecting insertions of setae j 2 and z 3, posterior to seta s 1; gdj 4 (po 2) close to line connecting insertions of setae j 4 and z 4; gdz 5 (po 3) located on posterior edge of podonotal shield, close to line connecting insertions of setae s 5 and z 6, which is different from typical location of po 3 in other species of new genus Sayanozercon. Five pairs of lyrifissures: idj 1, idj 3, idz 4, ids 4, idj 6 presented. Opisthonotal shield with delicate reticulation. Opisthonotum with 21 pairs of setae. J - series with full set of setae, among which J 3, J 4 and J 5 shortest. Microsetae J 5 is located directly above medial posterodorsal cavities. Z - series with longest setae Z 3, Z 4 and Z 5, among which Z 4 and Z 5 extend beyond edge of shield. Setae S 3, S 4 and S 5 longest in S - series, extend beyond edge of shield. Setae of R - series medium length. Opisthonotal shield with four pairs of glands and 13 pairs of lyrifissures located as shown in Fig. 46: gland gdz 6 (Po 1) anteromedial to seta Z 1; gdZ 1 (Po 2) anterolateral to seta Z 1; gdZ 3 (Po 3) close to line connecting insertions of setae Z 3 and Z 4; gdZ 4 (Po 4) on posterior margin of shield behind insertion of seta S 5; lyrifissures: ids 6, idS 1, idz 6, idS 4, idZ 4, idJ 4, idJ 5, idJ 2, idJ 3, doubled idJ 1 and doubled idS 3. Posterodorsal cavities rounded curvings, all similar size, located at posterior margin of opisthonotal shield. Ventral idiosoma (Fig. 47). Base of tritosternum 35 – 37 long, 23 – 25 wide; paired laciniae with three distal branches. Sternal shield 73 – 75 long at midline, 80 – 83 wide at level st 2 setae; with setae st 1 – st 3 similar in length, 20 – 25, smooth and pointed; with three pairs of lyrifissures iv 1, iv 2 and iv 3 and one pair of glands gv 1. Epiginal shield 125 – 130 long and 95 – 105 wide with setae st 5 (20 – 25) on shield and pair of lyrifissures iv 5. Large endopodal sclerites between coxae III – IV and small ovate-oblong endopodal sclerites around posterior parts of coxae IV presented. Setae st 4 (18 – 20) located outside or on edge of large endopodal shield. Pair of long exopodal sclerites extends from coxae IV to coxae I, closely adjacent to peritrematal shields and bend to dorsal side anteriorly. Pair of peritrematal shields adjacent to additional latero-ventral shields anteriorly and free at level coxae III – IV. Posterior margin of peritrematal shield truncate at level seta S 1 not fused with ventrianal shield; with fibre brush of cuticular structure and with two rounded formations in inguinal region (gvi and ivi). Peritrematal shields with smooth and pointed setae r 3; with two lyrifissures ip 1, ip 2 and gland gp from each side. Peritremes short, 40 – 43. Latero-ventral shield weakly reticulated, extends from seta r 3 to R 6. Adgenital sclerites presented, each with 4 – 5 glands openings gv 2. Ventrianal shield 235 – 245 long, 330 – 340 wide at level seta Zv 2, with 21 smooth, pointed setae; with transversal reticulation from anterior margin to level setae Jv 3 and strip of darker cuticle on anterior margin of shield, 20 – 25 wide. Anterior margin of ventrianal shield with two shortest pairs of setae Jv 1 and Zv 1 (10 – 12). Other setae in J - series: Jv 2 (17 – 20), Jv 3 (30 – 33), Jv 4 (37 – 43), Jv 5 (55 - 65); other setae in Z - series: Zv 2 (15 – 17), Zv 3 (20 – 23), Zv 4 (20 – 23); para-anal setae 50 - 53, post-anal 40 – 43 long. Pair of glands gv 3 located at level of posterior edge of the anus. Five pairs of ventrianal lyrifissures present: ivo 1 – ivo 4 and ivp. Anal opening with two pairs of lyrifissures on each valve. Cribrum presented posteriorly of post-anal setae. Gnathosoma (Figs 48 – 50). Movable digit of chelicera 60 – 62 long, with three teeth in addition to apical hook; fixed digit the same length, with five teeth, including offset distal tooth (gabelzhan), and four teeth in masticatory surface in addition to apical hook; leaf-shaped pilus dentilis and apical sensorial depression presented (Fig. 48). Chelicera with long dorsal seta, lateral (antiaxial) and dorsal lyrifissures; with smooth arthrodial corona and suboval area (“ window ”) of thin cuticle on paraxial side. Epistome with irregularly serrated lateral edges, medial ridge and serrated middle process with median row of small spines (Fig. 49). Corniculi horn-like, internal malae extending beyond corniculi, with fimbriate lateral margins and smooth pointed apices (Fig. 50). Deutosternal groove with seven transverse denticulate rows. Hypostome with four pairs of setae, setae h 1 – h 3 smooth, h 1 (37 – 39) the longest, seta h 2 (18 – 20) shorter than h 3 (27 – 32), pc (25 – 27) serrated. Palpal chaetotaxy typical for genus Sayanozercon. Legs. Chaetotaxy of I – IV legs is typical for Zerconidae. Pretarsus of legs II – IV with ambulacral stalk, tarsi I with sessile claws. Coxae II with antero-dorsal spine. Male. (Figs 51 – 54, n = 9). Dorsal idiosoma. (Fig. 51). Dorsal idiosoma pear-shaped, 460 – 465 long, 325 – 330 wide. Ornamentation, adenotaxy and poroidotaxy of dorsal shields as in female. Podonotal and opisthonotal chaetotaxy of male as in female. Lengths of podonotal, opisthonotal setae and longitudinal distances between insertions of setae in opisthonotal series of male summarized in Table 6. Ventral idiosoma. (Fig. 52). Tritosterum form as in female. Sternal shield fused with genital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2. Sternigenital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2, 150 – 153 long with four pairs of setae st 1 – st 4 (15 – 17), three pairs of lyrifissures iv 1, iv 2 and iv 5, one pair of glands gv 1 and genital opening opposite coxae III, eugenital setae not visible under light microscopy. Peritrematal shields connected posteriorly to each other by fibre brush of cuticular structure; each with short peritrema, with smooth, pointed seta r 3, lyrifissures ip 1, ip 2 and gland gp. Posterior margins of peritrematal shields with two pairs of rounded formations hollow inside (inguinal poroids gvi and ivi). Latero-ventral shields shaped as in female, with weak longitudinal reticulation. Ventrianal shield with weak transversal reticulation, 200 – 205 long and 275 – 290 wide; with 19 smooth and pointed setae, setae Zv 1 not developed; with five pairs of lyrifissures ivo 1 – ivo 4, ivp and pair of glands gv 3. Length of ventrianal setae: Jv 1 (17 – 19), Jv 2 (15 – 18), Jv 3 (27 – 30), Jv 4 (35 – 37), Jv 5 (50 – 53), Zv 2 – Zv 4 (17 – 20), para-anal setae 43 - 47, post-anal 32 – 35 long. Multiple glands gv 2 with 4 – 5 openings located on anterior margin of ventrianal shield. Anal opening with two pairs of lyrifissures on each valve. Cribrum presented posteriorly of post-anal seta. Gnathosoma (Figs 53 – 54). Movable digit of chelicera 45 – 47 long, with three teeth in addition to apical hook, fixed digit the same length, with six teeth including offset lateral-distal tooth (gabelzhan), five teeth in masticatory surface, addition to apical hook; leaf-shaped pilus dentilis, apical sensorial depression presented (Fig. 53). Male chelicera with dorsal seta, lyrifissures and arthrodial corona as in female. Epistome (Fig. 54), corniculi, internal malae and palpal structures as in female. Legs. Chaetotaxy and morphology of legs as in female. Juveniles not found.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B12EFFF46AAD5399D98291E3.taxon	materials_examined	Material examined. Holotype female, Russia, KRASNOYARSKII KRAI, West Sayan Mt., Ergaki Ridge, 52 ° 46 ’ N, 93 ° 21 ’ E, 1117 – 1250 m a. s. l., taiga along Tushkanchik river, Abies sibirica – Pinus sibirica, in moss, 5. VII 2024, leg. I. I. Marchenko. Paratypes: 6 females, 8 males, same geographic and locality data as holotype; 1 male, Ergaki Ridge, 52 ° 50 ’ N, 93 ° 21 ’ E, 1000 m a. s. l., Abies sibirica forest, in litter and moss, 27. VI 2013, coll. A. Kostyunin; 1 female, Ergaki Ridge, pass Olenya Rechka, 52 ° 48 ’ N, 93 ° 14 ’ E, 1000 m a. s. l., 1479 m a. s. l., taiga with Abies sibirica – Pinus sibirica, in moss, 20. VII 2018, leg. I. I. Marchenko; KEMEROVO REGION, 1 female, mountain region Gornaya Shoria, environs of Tashtagol City, foot of Mustag Mt., Abies sibirica – Picea obovata – Pinus sibirica forest, 52 ° 58 ’ N, 87 ° 44 ’ E, 600 m a. s. l., 19. VI 2013, leg. I. I. Marchenko.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B12EFFF46AAD5399D98291E3.taxon	etymology	Etymology. New species S. mikhaili dedicated to my son Mikhail V. Marchenko for his invaluable assistance in expedition situations.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B12EFFF46AAD5399D98291E3.taxon	discussion	Remarks. Distinguishing characters of adults of Sayanozercon mikhaili sp. nov. are: large size of idiosoma; setae s 1 present on podonotal shield; opisthonotal shield with five short pairs of setae in J - series, among which J 3, J 4 and J 5 are micro setae; setae Z 3, Z 4, Z 5 longest in Z - series, Z 3 and Z 4 extend beyond the edge of shield; seta S 2 shortest in S - series, approach edge of shield; setae S 3, S 4 and S 5 long, extend beyond the edge of opisthonotal shield. Sayanozercon mikhaili sp. nov. differs from all others species of new genus by atypical position of gland gdz 5 (po 3) located close to posterior edge of podonotal shield, close to line connecting insertions of setae s 5 and z 6, close. Location of opisthonotal glands: gdz 6 (Po 1) anteromedial to seta Z 1; gdZ 1 (Po 2) anterolateral to seta Z 1. Internal malae with smooth pointed apices; fixed digit of chelicera with sexual dimorphism – five teeth in female versus six teeth in male.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B115FFF26AAD5556DC8E97C4.taxon	description	(Figures 55 – 61) Female (Figs 55 – 58, n = 2) Dorsal idiosoma (Fig. 55). Idiosoma oval shape, 445 – 450 long, 315 – 330 wide, without obvious ornamentation, divided into two shields that cover entire dorsal idiosoma. All dorsal setae smooth, pointed. Podonotal shield with 21 pairs of setae, including r 1 located in podonotal shield and r 3 seta located in peritrematal shield; seta r 3 is 4 times longer than r 1. Setae z 1 and z 2 lost. Length of podonotal setae, opisthonotal setae and longitudinal distances between insertions of opisthonotal setae in specific series female and male summarized in Table 7. Setae in j- series similar in length; setae s 1 shortest, setae z 4 longest in z - series; setae s 3 longest in s - series and among all podonotal setae. Seta r 1 shortest in r - series and among all podonotal setae. Podonotal shield with three pairs of glands: gdj 2 (po 1), gdj 4 (po 2), gdz 5 (po 3) which are located in typical positions for most species of genus Sayanozercon. Location of podonotal glands: gdj 2 (po 1) close to line connecting insertions of setae j 2 and z 3, posrerior to insertion of seta s 1; gdj 4 (po 2) close to line connecting insertions of setae j 4 and z 4; gdz 5 (po 3) close and anterior to line connecting insertions of setae z 5 and s 5. Five pairs of podonotal lyrifissures: idj 1, idj 3, idz 4, ids 4, idj 6 presented. Opisthonotal shield with delicate reticulation. Opisthonotal shield with 21 pairs of setae. Setae of J - series with full set, among which J 3, J 4 and J 5 microsetae. Setae J 5 is located directly above medial posterodorsal cavities. Z - series with longest setae Z 3, Z 4 and Z 5, among which Z 4 and Z 5 extend beyond edge of shield. Setae S 3, S 4 and S 5 extend beyond edge of shield, among them setae S 4 and S 5 longest in S - series. Setae of R - series all long. Opisthonotal shield with four pairs of glands and 13 pairs of lyrifissures. Location of opisthonotal glands: gdz 6 (Po 1) anteromedial to seta Z 1; gdZ 1 (Po 2) on line connecting insertions of setae Z 1 and Z 2; gdZ 3 (Po 3) close to line connecting insertions of setae Z 3 and Z 4; gdZ 4 (Po 4) on posterior margin of shield behind insertion of seta S 5. Location of lyrifissures shown in Fig. 55: ds 6, idS 1, idz 6, idS 4, idZ 4, idJ 4, idJ 5, idJ 2, idJ 3, doubled idJ 1 and doubled idS 3. Posterodorsal cavities rounded curvings, all similar size, located at posterior margin of opisthonotal shield. Ventral idiosoma (Fig. 56). Base of tritosternum 25 – 27 long, 18 – 20 wide; paired laciniae with three distal branches. Sternal shield 63 – 65 long at midline, 67 – 70 wide at level st 2 setae; with setae st 1 – st 3 similar in length, 17 – 19, smooth and pointed; with three pairs of lyrifissures iv 1, iv 2 and iv 3 and one pair of glands gv 1. Epiginal shield 100 – 107 long and 65 – 67 wide with setae st 5 (17 – 19) on shield and pair of lyrifissures iv 5. Large endopodal sclerites between coxae III – IV and small ovate-oblong endopodal sclerites around posterior parts of coxae IV presented. Setae st 4 (15 – 17) located outside of large endopodal shield. Pair of long exopodal sclerites extends from coxae IV to coxae I, closely adjacent to peritrematal shields and bend to dorsal side anteriorly. Pair of peritrematal shields adjacent to additional latero-ventral shields anteriorly and free at level coxae III – IV. Peritrematal shield truncate at posterior margin, not fused with ventrianal shield; with fibre brush of cuticular structure and with two rounded formations in inguinal region (gland gvi and lyrifissure ivi) from each side. Peritrematal shields with smooth and pointed setae r 3; two lyrifissures ip 1, ip 2 and gland gp from each side. Peritremes short, 35 – 37. Pair of latero-ventral shields weakly longitudinal reticulated, extends from seta r 3 to R 6. Adgenital sclerites presented each with 4 glands openings gv 2. Ventrianal shield 187 – 190 long, 245 – 255 wide at level seta Zv 2, with 21 smooth, pointed setae; with narrow strip of transversal reticulation Anterior margin of ventrianal shield with two shortest pairs of setae Jv 1 and Zv 1 (8 – 10). Other setae in J - series: Jv 2 (15 – 17), Jv 3 (28 – 30), Jv 4 (37 – 39), Jv 5 (50 – 52); other setae in Z - series: Zv 2 (13 – 15), Zv 3 (18 – 20), Zv 4 (10 – 12); para-anal setae 50 – 53, post-anal 33 – 35 long. Pair of glands gv 3 located at level of posterior edge of the anus. Five pairs of ventrianal lyrifissures present: ivo 1 – ivo 4 and ivp. Anal opening with two pairs of lyrifissures on each valve. Cribrum presented posteriorly of post-anal setae. Gnathosoma (Figs 57 – 58). Movable digit of chelicera 48 – 50 long, with three teeth in addition to apical hook, fixed digit the same length, with five teeth, including offset lateral-distal tooth (gabelzhan), followed by four teeth in masticatory surface in addition to apical hook; pilus dentilis, dorsal seta, cheliceral lyrifissures and arthrodial corona not visible (Fig. 57). Epistome with irregularly serrated lateral edges, with medial ridge and serrated middle process, with median row of small spines (Fig. 58). Corniculi horn-like, internal malae extending beyond corniculi, with fimbriate lateral margins and bifurcate apices (Fig. 57). Deutosternal groove with seven transverse denticulate rows. Hypostome with four pairs of setae, setae h 1 – h 3 smooth, h 1 (37 – 39) the longest, seta h 2 (15 – 16) shorter than h 3 (25 – 26), pc (25 – 27) serrated. Palpal chaetotaxy typical for genus Sayanozercon. Legs. Chaetotaxy of I – IV legs is typical for Zerconidae and Sayanozercon. Pretarsus of legs II – IV with ambulacral stalk, tarsi I with sessile claws. Coxae II with antero-dorsal spine. Male. (Figs 59 – 61, n = 2). Dorsal idiosoma. (Fig. 59). Dorsal idiosoma oval-shaped, 365 – 375 long, 245 – 260 wide. Ornamentation, adenotaxy and poroidotaxy of dorsal shields as in female. Podonotal and opisthonotal chaetotaxy of male as in female. Lengths of podonotal, opisthonotal setae and longitudinal distances between insertions of setae in opisthonotal series of male summarized in Table 7. Ventral idiosoma. (Fig. 60). Tritosterum form as in female. Sternal shield fused with genital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2. Sternigenital shield with area of weak sclerotisation and weak reticulation between setae st 1 and st 2, 137 – 140 long with four pairs of setae st 1 – st 4 (15 – 17), three pairs of lyrifissures iv 1, iv 2 and iv 5, one pair of glands gv 1 and genital opening opposite coxae III, eugenital setae not visible under light microscopy. Peritrematal shields connected posteriorly to each other by fibre brush of cuticular structure; each with short peritrema (32 – 33), smooth and pointed seta r 3, lyrifissures ip 1, ip 2 and gland gp. Posterior margins of peritrematal shields with two pairs of rounded formations hollow inside (inguinal poroids gvi and ivi). Latero-ventral shields shaped as in female, with weak longitudinal reticulation. Ventrianal shield without ornamentation, 155 – 157 long and 220 – 225 wide; with 19 smooth and pointed setae, setae Zv 1 lost; with five pairs of lyrifissures ivo 1 – ivo 4, ivp and pair of glands gv 3. Length of ventrianal setae: Jv 1 (10 – 12), Jv 2 (12 – 15), Jv 3 (23 – 25), Jv 4 (30 – 32), Jv 5 (47 – 50), Zv 2 (10 – 12), Zv 3 – Zv 4 (13 – 15), para-anal setae 47 – 50, post-anal 30 – 32 long. Multiple glands gv 2 with 4 openings located on anterior margin of ventrianal shield. Anal opening with two lyrifissures on each valve. Cribrum presented posteriorly of post-anal seta. Gnathosoma. Movable digit of chelicera 37 – 39 long, with three teeth in addition to apical hook, fixed digit the same length, with offset lateral-distal tooth (gabelzhan), number of other teeth, dorsal seta, lyrifissures and arthrodial corona are not clearly distinguished. Epistome (Fig. 61), corniculi, internal malae and palpal structures as in female. Legs. Chaetotaxy and morphology of legs as in female. Juveniles not found.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B115FFF26AAD5556DC8E97C4.taxon	materials_examined	Material examined. Holotype female, Russia, KEMEROVO REGION, Gornaya Shoria mountain massif, Mrassu river valley, environs of Kabyrza village, 52 ° 50 ’ N, 88 ° 47 ’ E, 460 m a. s. l., under Pinus sylvestris, in litter, 18. VIII 2015, coll. L. A. Trilikauskas. Paratypes: 1 female, same geographic and locality data as holotype; 2 males, KEMEROVO REGION, environs of Mezhdurechensk City, 53 ° 41 ’ N, 88 ° 06 ’ E, 425 m a. s. l., under Calamagrostis sp., in litter, 28. V 1981, coll. V. V. Nikolskii.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B115FFF26AAD5556DC8E97C4.taxon	etymology	Etymology. New species S. shoricus is named after Gornaya Shoria mountain massif in Kemerovo Region in southern Siberia of Russia, where the type material of this species was found.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
038B87E0B115FFF26AAD5556DC8E97C4.taxon	discussion	Remarks. Distinguishing characters of adults of Sayanozercon shoricus sp. nov. are: mid-size of idiosoma; seta s 1 present on podonotal shield; podonotal gland gdz 5 (po 3) located close and anterior to line connecting insertions of setae z 5 and s 5; opisthonotal gland gdZ 1 (Po 2) located on line connecting insertions of setae Z 1 and Z 2, what differs from four others species of new genus Sayanozercon. Opisthonotal shield with five short pairs of setae in J - series, among which J 3, J 4 and J 5 are microsetae; setae Z 3, Z 4, Z 5 longest in Z - series, Z 3 approach edge of shield and Z 4 extend beyond the edge of shield; setae S 1, S 2 shortest in S - series, S 2 approach edge of shield; setae S 3, S 4 and S 5 long, extend beyond edge of opisthonotal shield. Internal malae with bifurcate apices.	en	Marchenko, Irina I. (2025): The new genus Sayanozercon (Acari: Mesostigmata: Zerconidae) with description of five new species from South Siberia mountains (Russia). Zootaxa 5647 (2): 151-195, DOI: 10.11646/zootaxa.5647.2.5, URL: https://doi.org/10.11646/zootaxa.5647.2.5
