Epidamaeus hexatuberculatus Ermilov et Salavatulin, 2022

Ermilov, S. G. & Salavatulin, V. M., 2022, A new species of the genus Epidamaeus Bulanova-Zachvatkina, 1957 (Acari: Oribatida: Damaeidae) from Western Siberia, Far Eastern Entomologist 450, pp. 1-8 : 3-8

Epidamaeus hexatuberculatus Ermilov et Salavatulin , sp. n.

http://zoobank.org/NomenclaturalActs/ AB12E495-A525-4F71-93C4-4EECB7062682

Figs 3–9

TYPE MATERIAL. Holotype – ♀, Russia: Western Siberia , Tyumen Region,

Tobolsk District, nearly Nadtsy Settlement, 58.631796 o N, 68.566218 o E, soil-litter in mixed forest (birch-pine-cedar), 30.VII 2015, collected by V.M. Salavatulin .

Paratypes: the same label as holotype, 1♂, 2♀; Russia: Western Siberia , Khanty-

Mansiysk Autonomous Region, Nephteyugansk District, nearly Kut-Yakh Settlement, 60.351376 o N, 72.099673 o E, soil-litter in mixed forest (spruce-birch-cedar),

23.VII 2015, 2♂, ♀, collected by V.M. Salavatulin .

TYPE DEPOSITION. The holotype is deposited in the collection of the

Senckenberg Museum of Natural History, Görlitz, Germany; seven paratypes are deposited in the collection of the Tyumen State University Museum of Zoology,

Tyumen, Russia. All specimens are preserved in 70% solution of ethanol with a drop of glycerol.

DIAGNOSIS. Body length: 531–630. Cerotegument filamentous. Exuvial scalps usually present on notogaster. Propodolateral apophysis absent. Three pairs of simple prodorsobasal tubercles (Da, Ba, Bp); Da located anteromedial to Ba.

Rostral and lamellar setae setiform, barbed. Interlamellar seta narrowly phylliform.

Bothridial seta rod-like, barbed. Spina adnata of medium length, thorn-like. Notogastral setae of c -, l - and h -series phylliform, p 1, p 2 and p 3 setiform, barbed. Ventral enantiophyses E2 and V absent; mediosejugal enantiophysis well-developed. Parastigmatic tubercle Sa long, thorn-like, Sp tubercle-like. Epimeral setal formula: 3-1-3-4.

Epimeral and anogenital setae setiform, slightly barbed. Discidium tubercle-like. Legs

I and IV longer than body length; leg IV longest. Formulas of leg segments (I-IV):

femur 7-6-4-4; genu and tibia 4-4-3-3; tarsus 21-18-18-15. Seta v 2 ’ present on all tarsi.

DESCRIPTION. Measurements. Body length: 581 (holotype) , 498 (male paratypes); 531–630 (female paratypes); notogaster width: 381 (holotype), 315–332

(male paratypes); 332–381 (female paratypes).

4 – ventral view (gnathosoma and legs not shown); 5 – notogaster and basal part of prodorsum,

lateral view. Scale bar 100 μm.

leg II, without tarsus, right, dorsoantiaxial view; 8 – leg III, without tarsus, trochanter turned,

left, antiaxial view; 9 – leg IV, left, antiaxial view. Scale bar 50 μm.

Integument. Color medium to dark brown in preserved mature adults. Cerotegument conspicuous, excrescences varying in length but mostly filamentous on body and legs; setae usually without cerotegument. Procuticle mostly smooth.

Usually with full stack of juvenile exuvial scalps, often with other adherent structures,

particularly eggs or eggshells and fecal pellets, but without compacted organic debris.

Prodorsum. Rostrum rounded. Propodolateral apophysis absent. Prodorsobasal tubercle Da and postbothridial enantiophysis (Ba, Bp) well developed, subconical,

distally rounded, similar in size; Da located clearly anteromedial to Ba; laterosejugal enantiophysis absent. Rostral (77–82) and lamellar (102–106) setae setiform, barbed;

le thicker than ro. Indistinct transverse furrow between insertions of lamellar setae.

Interlamellar seta (69–73) narrowly phylliform, directed mediad or posteromediad.

Bothridial seta (221–225) rod-like, barbed. Bothridium with projecting part goblet-

shaped, with vertical banding; mutual distance of openings slightly greater than that of tubercles Ba. Anterobothridial ridge present. Exobothridial seta (49–57) setiform,

slightly barbed. Alveolar vestige of second exobothridial seta present posterior to seta ex.

Notogaster. Nearly circular in outline; uniformly curved, hemispherical with maximum height in middle. Spina adnata (41–53) shorter than a mutual distance of pair, thorn-like, directed anterolaterad, reaching or surpassing level of tubercle Ba

(sometimes Da). Dorsal notogastral setae (c -, l - and h -series) directed radially,

inserted in uniformly curving, nearly semicircular row; c 1, c 2 (73–82) and la, lm, lp,

h 3 (57–61) relatively broadly phylliform, h 1 and h 2 (41–45) narrowly phylliform, p 1,

p 2 and p 3 (57–61) setiform, barbed. Opisthonotal gland opening, notogastral lyrifissures ia, im, ip, ih and ips and circumgastric sigillar band all distinct in trans-

mitted light.

Gnathosoma. Typical for Epidamaeus (Norton & Ermilov 2021) . Subcapitulum size: 110–123 × 73–77. Subcapitular setae (a: 28–32; m and h: 49–53) setiform,

slightly barbed. Adoral seta (12) setiform, straight, roughened. Palp (94–102) with the typical formula: 0-2-1-3-9(+ω); ω baculiform, appressed to surface. Postpalpal seta (8) spiniform, roughened. Chelicera (110–123) with two setiform setae; cha

(41) barbed, chb (28) unilaterally ciliate in mediodistal part.

Epimeral and lateral podosomal regions. Tectum of podocephalic fossa normally developed, without lateral tooth-like projection. Medial coxisternal pit present on epimere I, shallow, with vaguely defined margins. Enantiophyses E2 and V are absent. Parastigmatic enantiophysis strongly dimorphic: Sa long, thorn-like; Sp

tubercle-like, distally rounded, directed nearly perpendicular to Sa. Mediosejugal enantiophysis distinct, just anterior to genital aperture; tubercles simple, Ma larger than Mp. Epimeral setal formula: 3-1-3-4. All setae (1a, 2a, 3a: 32–36; 1c: 24–32;

others: 57–61) setiform, slightly barbed; 1c inserted on small but distinct tubercle;

3c removed medially from tubercle Sp and acetabulum III. Discidium poorly developed, tubercle-like.

Anogenital region. Genital, aggenital, anal and adanal setae similar in length (41–

45), setiform, slightly barbed. Adanal lyrifissure oriented diagonally.

Legs. Leg III similar to body in length, leg II shorter than body length, legs I and IV longer than body length, leg IV longest; approximate length of leg segments shown in Table 1. Claw of each tarsus smooth. Porose area on femora I-IV and on trochanters III and IV distinctly visible. Formulas of leg setation and solenidia: I (1-

7-4-4-21) [1-2-2], II (1-6-4-4-18) [1-1-2], III (2-4-3-3-18) [1-1-0], IV (1-4-3-3-15)

[0-1-0]; homology of setae and solenidia indicated in Table 2. Solenidion on genua

I-III shorter than coupled setae d. Famulus of tarsus I short, setiform, inserted between solenidia ω 1 and ω 2. Seta v 2 ’ present on all tarsi.

ETYMOLOGY. The species name refers to the presence of six prodorsobasal tubercles (paired Da, Ba and Bp).

REMARKS. Epidamaeus hexatuberculatus sp. n. is morphologically most similar to Epidamaeus nortoni Bayartogtokh, 2004 from Mongolia and E. tritylos

Behan-Pelletier et Norton, 1983 from the Palaearctic region in having three pairs of prodorsobasal tubercles and phylliform dorsal notogastral setae. However, the new species differs from both by the absence (vs. presence) of enantiophyses E2 and V, the presence (vs. absence) of mediosejugal enantiophysis, narrowly phylliform (vs. setiform) interlamellar seta and tubercle-like, rounded distally (vs. triangular, pointed distally) discidium, and the localization of prodorsobasal tubercle Da (distinctly anteromedial to Ba vs. medial to Ba). Also, E. nortoni has four pairs (vs. one pair)

of setae on the epimere II and does not have a parastigmatic tubercle Sa (vs. well developed); E. tritylos has bacilliform (vs. rod-like) bothridial seta.

Figures

Figs 3–5. Epidamaeus hexatuberculatus sp. n., adult: 3 – dorsal view (legs not shown);

Figs 6–9. Epidamaeus hexatuberculatus sp. n., adult: 6 – leg I, right, antiaxial view; 7 –