# Two new species of Caligonellidae (Acari: Raphignathoidea) from Western Siberia, Russia

Alexander A Khaustov

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## To cite this version:

Alexander A Khaustov. Two new species of Caligonellidae (Acari: Raphignathoidea) from Western Siberia, Russia. Acarologia, 2022, 62 (1), pp.99-112. 10.24349/1dwx-x5h2. hal-03542199

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Submitted on 25 Jan 2022

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# Two new species of Caligonellidae (Acari: Raphignathoidea) from Western Siberia, Russia

Alexander A. Khaustovª

## Original research

### ABSTRACT

Female, male, deutonymph and protonymph of *Molothrognathus altaicus* n. sp., and female and deutonymph of *Neognathus sibiriensis* n. sp. (Caligonellidae) are described from soil from Altai Republic and Tyumen Region, respectively.

**Keywords** Prostigmata; mites; *Neognathus*; *Molothrognathus*; systematics; morphology

**Zoobank** http://zoobank.org/B6FC7B64-7DC1-4B67-80A3-69F693015950

## Introduction

The family Caligonellidae is a small group of predatory prostigmatid mites, which comprises 5 genera and about 60 species distributed almost worldwide, except Australia and Antarctica (Beron 2020; Khaustov 2021). The caligonellid mites of Asian part of Russia are completely unstudied.

The genus *Molothrognathus* Summers and Schlinger, 1955 comprises 29 described species (see Khaustov 2021).

The genus *Neognathus* Willmann, 1952 comprises 14 valid species: *N. insolitus* Willmann, 1952 (Germany), *N. terrestris* (Summers and Schlinger, 1955) (Canada, Hungary, Iran, Russia, Turkey, USA), *Neognathus spectabilis* (Summers and Schlinger, 1955) (Canada, Hungary, Iran, Latvia, Russia, USA), *N. orientalis* Soliman, 1971 (Egypt), *N. cinis* Chaudhri, Akbar and Rasool, 1979 (Pakistan), *N. eupalopus* Smith Meyer and Ueckermann, 1989 (South Africa, Turkey), *N. davei* Smith Meyer and Ueckermann, 1989 (South Africa), *N. jieliui* Hu and Yu, 1995 (China), *N. linanensis* Hu, 1995 (China), *N. ozkani* Akyol and Koç, 2012 (Turkey), *N. pusillus* Doğan and Doğan, 2019 (Turkey), *N. rijabicus* Nazari, Khanjani and Kamali, 2013 (Iran). *N. sinaei* Samadpour, Khanjani and Asalifayaz, 2014 (Iran), and *N. ueckermanni* Bagheri, Doğan and Haddad Irani-Nejad, 2010 (Iran, Turkey) (Beron 2020). *Neognathus harteni* Ueckermann, 2008 (UAE) should belong to the genus *Paraneognathus* Fan, 2000 in having characteristic ω-shaped peritremes and presence of two setae on palp femur (always one in *Neognathus*).

During the study of predatory mites of Russia, two new species, *Molothrognathus altaicus* n. sp. and *Neognathus sibiriensis* n. sp. were collected from soil in Altai Republic and Tyumen Region, respectively. The aim of this paper is to describe and illustrate these new species.

## Material and methods

Mites were collected from the soil samples by Berlese-Tullgren funnels. Collected mites were mounted in Hoyer's medium. Notation applied to the body and leg setae follow that of Grandjean's system, overviewed by Kethley (1990) and Norton (1977) applied to Caligonellidae by Swift (2001); palpal setation follows Grandjean (1946). Mite morphology was studied using

Received 28 December 2021

Accepted 24 January 2022

Published 25 January 2022

Corresponding author
Alexander A. Khaustov:
alex1973khaustov@gmail.com

Academic editor
Faraji, Farid

https://doi.org/
10.24349/1dwx-x5h2

ISSN 0044-586X (print)
ISSN 2107-7207 (electronic)

CC Copyright
Khaustov A. A.

Distributed under
Creative Commons CC-BY 4.0

<footnote>ªTyumen State University, Tyumen, Volodarskogo 6, 625003 Russia.</footnote>
an AxioImager A2 compound microscope (Carl Zeiss, Germany) with phase-contrast and differential interference contrast (DIC) illumination. Photomicrographs were taken with an AxioCam IC5 digital camera. All measurements are given in micrometers (µm) for holotype and available paratypes (in parentheses). For leg chaetotaxy, the number of solenidia is given in parentheses.

**Results Systematics**

**Family Caligonellidae Grandjean**

**Genus Molothrognathus Summers and Schlinger, 1955**

Type species: *Molothrognathus leptostylus* Summers and Schlinger, 1955, by original designation

**Molothrognathus altaicus n. sp.**

Zoobank: 111B34FE-B677-4708-865C-45AAC830DD79

(Figures 1–6)

**Diagnosis**

**Female.** Dorsal shield absent, three pairs of aggenital setae, setae sce and c2 much longer than c1 and other prodorsal setae, seta p'' of tarsus II absent.

**Description**

**Female** (Figs 1-3) — Length of idiosoma 335 (310–360), width 210 (155–210).

*Idiosomal dorsum* (Fig. 1A) – Ovate. Dorsal idiosomal striae thin, usually double; dorsal shield absent. Two pairs of ocelli located posterolaterad setae *sci*, anterior ocellus slightly smaller than posterior. Cupuli *ia*, *im* and *ip* large, almost round; *ia* located just posteromesad posterior ocellus, *im* anterolaterad *d*, and *ip* anterolaterad *f*. All dorsal idiosomal setae smooth and pointed; setae *c2* much longer than *c1* and *sci* and slightly shorter than *sce*; setae *f*, *h1* and *h2* much longer than *c1*, *d* and *e*. Anal valves located dorsoterminal, with two pairs of pseudanal setae. A pair of longitudinal, almost parallel rows of tiny subcuticular sclerites situated laterad setae *c1* and *d*. Lengths of dorsal setae: *vi* 26 (24–25), *ve* 25 (23–24), *sci* 26 (23–25), *sce* 83 (77–84), *c1* 22 (21–22), *c2* 66 (57–61), *d* 20 (18–20), *e* 29 (25–26), *f* 64 (59–62), *h1* 53 (48–51), *h2* 54 (51–53), *ps1* 14 (11–12), *ps2* 13 (10–12).

*Idiosomal venter* (Fig. 1B) – Ventral idiosoma striated, without plates. All ventral setae smooth and pointed. Three pairs of aggenital and one pair of genital setae; cupuli *ih* located anterolaterad *g*. A pair of almost parallel rows of small subcuticular sclerites situated laterad setae *4a*; two pairs of tiny subcuticular sclerites located just posteriad coxal fields II. Lengths of ventral setae: *1a* 37 (34–36), *1b* 29 (26–27), *1c* 24 (22), *2c* 26 (23–26), *3a* 41 (36–37), *3b* 28 (24), *4a* 31 (28–30), *4c* 29 (25–28), *ag1* 33 (29), *ag2* 24 (20), *ag3* 12 (11), *g* 27 (26–27).

*Gnathosoma* (Fig. 2) – Stylophore subtriangular, split distally, longitudinally striated, its width 43 (42–44); peritremes tubular, typical for the genus; peritremes inside with fine striae; cheliceral levers large, oval. Palpal supracoxal setae (*ep*) located in deep depression with terminal pore; palpal chaetotaxy: Tr 0, Fe 1 (*d*), Ge 1 (*d*), Ti 3 (*d*, *l'*, *l''*), Ta 7(1) (*ba*, *bp*, *va*, *acmζ*, *ul'ζ*, *ul''ζ*, *sulζ*, *ω*); tibial claw large, slightly hooked; all palpal setae smooth, eupathidia *acmζ*, *ul'ζ*, *ul''ζ*, *sulζ* distinctly widened distally, with four subapical flat lobes, other palpal setae pointed. Subcapitulum smooth; all subcapitular setae smooth, and pointed; lengths of subcapitular setae: *m* 46 (41–43), *or1* 9 (7–9), *or2* 7 (6–7), length of palptarsal solenidion *ω* 4 (3–4).

*Legs* (Fig. 3) – Lengths of legs (excluding claws): I 225 (210–230), II 150 (150–160), III 170 (165–170), IV 185 (180–190). Leg I (Fig. 3A) longer than other legs. Leg setation: Tr 1
<figure><img src="image_8.png" /><figcaption>**Figure 1** *Molothrognathus altaicus* n. sp., female: A – idiosomal dorsum, B – idiosomal venter.*</figcaption></figure>

(v'), Fe 2 (d, bv''), Ge 6 (d, l', l'', v', v'', k), Ti 5(2) (d, l', l'', v', v'', φ, φρ), Ta 16(1) (ft', ft'', tc'ζ, tc''ζ, p'ζ, p''ζ, it', a', a'', u', u'', vs, pv', pv'', pl', pl'', ω). Supracoxal seta of leg I (el) located in deep depression with terminal pore; seta k of genu situated in shallow depression; all leg setae smooth; setae (tc) and (p) eupathid-like, blunt-tipped, other leg setae pointed; solenidion ω 8 (8) digitiform, solenidia φ 3 (3) and φρ 9 (9–10) baculiform. Leg II (Fig. 3B). Leg setation: Tr 1 (v'), Fe 2 (d, bv''), Ge 5 (d, l', l'', v', v''), Ti 5 (d, l', l'', v', v''), Ta 10(1) (ft', tc', tc'', it'', a', a'', u', u'', pv', pv'', ω). All leg setae smooth and pointed; seta p''ζ absent; solenidion ω 7 (7) digitiform. Leg III (Fig. 3C). Leg setation: Tr 1 (v'), Fe 2 (d, ev'), Ge 2 (d, v'), Ti 4 (d, l'', v', v''), Ta 9 (tc', tc'', it', a', a'', u', u'', pv', pv''). All leg setae smooth and pointed. Leg IV (Fig. 3D). Leg setation: Tr 1 (v'), Fe 2 (d, ev'), Ge 2 (d, v'), Ti 4 (d, l'', v', v''), Ta 9 (tc', tc'', it', a', a'', u', u'', pv', pv''). All leg setae smooth and pointed.

**Male** (Fig. 4) — Idiosoma narrower posteriorly than in female. Length of idiosoma 250–270, width 120–135.

*Idiosomal dorsum* (Fig. 4A) – Striation similar with that of female, except presence of pygidial shield with setae *h1* and *f*. Setae *d* and *e* distinctly longer than in female; setae *h1* and *ps1* very short, weakly blunt-tipped. Lengths of dorsal setae: *vi* 20, *ve* 20–21, *sci* 22–23, *sce* 69–73, *c1* 18–19, *c2* 56–57, *d* 36–37, *e* 54–58, *f* 40–41, *h1* 2–3, *h2* 42–43, *ps1* 2, *ps2* 5–6. Aedeagus well sclerotized, long, thickened in central part.

*Idiosomal venter* (Fig. 4B) – Ventral idiosoma completely striated. Two pairs of aggenital
<figure><img src="image_9.png" /><figcaption>**Figure 2** *Molothrognathus altaicus* n. sp., female: A – gnathosoma, dorsal aspect, B – subcapitulum.</figcaption></figure>

setae; genital setae absent. Other characters as in female. Lengths of ventral setae: *1a* 25–29, *1b* 20–21, *1c* 19, *2c* 20–21, *3a* 30, *3b* 19–23, *4a* 19–20, *4c* 20–22, *ag1* 21, *ag2* 30.

*Gnathosoma* as in female. Width of stylophore 32–35, lengths of setae: *m* 35–38, *or1* 6–7, *or2* 5–6, length of palptarsal solenidion *ω* 3–4.

*Legs* as in female. Lengths of legs: I 170–180, II 120–125, III 130–140, IV 130–150. Solenidia *ω*I 7, *φ* 2, *φρ* 6–7, *ω*II 3–4, seta *k* 4.

**Deutonymph** (Fig. 5) — Length of idiosoma 315, width 180.

*Idiosomal dorsum* (Fig. 5A) – Similar with that of female. Lengths of dorsal setae: *vi* 23, *ve* 20, *sci* 22, *sce* 73, *c1* 20, *c2* 56, *d* 19, *e* 22, *f* 55, *h1* 48, *h2* 48, *ps1* 9, *ps2* 10.

*Idiosomal venter* (Fig. 5B) – Similar with that of female, except absence of genital opening and genital setae. Lengths of ventral setae: *1a* 31, *1b* 23, *1c* 19, *2c* 21, *3a* 32, *3b* 25, *4a* 24, *4c* 21, *ag1* 21, *ag2* 27, *ag3* 10.

*Gnathosoma* as in female. Width of stylophore 38, lengths of setae: *m* 37, *or1* 8, *or2* 6, length of palptarsal solenidion *ω* 4.

*Legs* as in female. Lengths of legs: I 190, II 130, III 150, IV 160. Solenidia *ω*I 7, *φ* 2, *φρ* 8, *ω*II 4, seta *k* 4.

**Protonymph** (Fig. 6) — Length of idiosoma 195–265, width 100–160.

*Idiosomal dorsum* (Fig. 6A) – Similar with that of female. Lengths of dorsal setae: *vi*
<figure><img src="image_10.png" /><figcaption>**Figure 3** *Molothrognathus altaicus* n. sp., female: A-D – right legs I-IV respectively, dorsal aspect.</figcaption></figure>
<figure><img src="image_11.png" /><figcaption>**Figure 4** *Molothrognathus altaicus* n. sp., male: A – idiosomal dorsum, B – idiosomal venter. Striation of soft cuticle not illustrated.</figcaption></figure>

16–18, *ve* 17–19, *sci* 17–18, *sce* 66–68, *c1* 16, *c2* 45–46, *d* 16, *e* 20, *f* 45–48, *h1* 42, *h2* 39, *ps1* 10, *ps2* 10.

*Idiosomal venter* (Fig. 5B) – Similar with that of female, except absence of genital opening and setae 4a, 4c, *ag2*, *ag3* and *g*. Lengths of ventral setae: *la* 26–27, *1b* 19–20, *1c* 16, *2c* 18, *3a* 27, *3b* 16–18, *ag1* 18.

*Gnathosoma* as in female. Width of stylophore 31–33, lengths of setae: *m* 27, *or1* 6, *or2* 5, length of palptarsal solenidion *ω* 3.

*Legs* I–III as in female. Lengths of legs: I 155, II 110–115, III 125, IV 130–135. Solenidia *ω*I 6, *φ* 2, *φρ* 5–6, *ω*II 3, seta *k* 4. Leg IV without setae *v'* of trochanter, *d* of femur and genu and *it'* of tarsus.

**Type material**

Female holotype, slide ZISP T-Cal-03, Russia, Altai Republic, Kosh-Agach, 1765 m a.s.l., 49°57′35.4″ N 88°43′04.8″ E, 15 July 2021, in dry soil in the steppe, coll. A.A. Khaustov. Paratypes: 3 females, 5 males, 1 deutonymph, 4 protonymphs, same data.

**Type deposition**

The holotype, one female and one male paratypes of the new species are deposited in the acarological collection of the Zoological Institute of RAS, St. Petersburg, Russia; paratypes are
<figure><img src="image_12.png" /><figcaption>**Figure 5** *Molothrognathus altaicus* n. sp., deutonymph: A – idiosomal dorsum, B – idiosomal venter. Striation of soft cuticle not illustrated.</figcaption></figure>

deposited in the mite collection of the Tyumen State University Museum of Zoology, Tyumen, Russia.

**Etymology**

The name of the new species refers to geographical distribution in Altai.

**Differential diagnosis**

Female of the new species is most similar to *M. bahariensis* Ueckermann and Khanjani, 2003, *M. azizi* Ueckermann and Khanjani, 2003, *M. saudiensis* Halawa, 2013 and *M. fulgidus* Summers and Schlinger, 1955 in having setae *sce* longer than other prodorsal setae, in absence of dorsal idiosomal shield, and in presence of seta *ag3*. The new species differs from *M. bahariensis* in having setae *c2* shorter than *sce* (subequal in *M. bahariensis*), in having setae *c2* (57–66), *sce* (77–84) and *f* (59–64) much shorter (*c2* 113–142, *sce* 101–139, *f* 91–123 in *M. bahariensis*). The new species differs from *M. azizi* in having setae *c2* shorter than *sce* (subequal in *M. azizi*), in having setae *f* longer than *h1* (*f* shorter than *h1* in *M. azizi*), and in having 16 setae on tarsus I (15 in *M. azizi*). The new species differs from *M. saudiensis* in having nine setae on tarsi III
<figure><img src="image_13.png" /><figcaption>**Figure 6** *Molothrognathus altaicus* n. sp., protonymph: A – idiosomal dorsum, B – idiosomal venter. Striation of soft cuticle not illustrated.</figcaption></figure>

and IV (eight in *M. saudiensis*), 10 tactile setae on tarsus II (nine in *M. saudiensis*) and much shorter setae *ve* (23–25) and *sci* (23–26) (*ve* 50–60, *sci* 53–59 in *M. saudiensis*). The new species differs from *M. fulgidus* in having setae *f* much longer than *e* (*e* and *f* subequal in *M. fulgidus*).

**Genus Neognathus Willmann, 1952**

Type species: *Neognathus insolitus* Willmann, 1952, by original designation

**Neognathus sibiriensis n. sp.**

Zoobank: 14E92361-B739-49CB-874B-2603EC02F309
(Figures 7–11)

**Diagnosis**

**Female.** Cupuli *ia* well developed, tarsi III and IV with eight setae each (*vs* present), genu III with two setae, tarsus IV without solenidion, tibia IV with solenidion, palpgenu with one seta, stylophore without lateral projections, peritremes with four pairs of segments, two pairs of pseudanal setae, with small area of transverse striae anteromesad setae *c1*.

**Description**

**Female** (Figs 7-10) — Length of idiosoma 255 (255–290), width 140 (140–165).
*Idiosomal dorsum* (Figs 7A, 10A) – Ovate. Dorsal idiosomal striae thin; small area of transverse striae situated anteromesad setae *c1* (Figs 7A, 10A). Dorsal setae smooth, pointed. Cupuli *ia*, *im* and *ip* large, almost round; *ia* located posterolaterad *c1*, *im* anterolaterad *e*, and *ip* anterolaterad *f*. Anterior part of longitudinal rows of small sclerites curved medially anteriad setae *c1*. Lengths of dorsal setae: *vi* 9 (9–11), *ve* 12 (10–14), *sci* 14 (14–15), *sce* 12 (12–14), *c1* 12 (12–13), *c2* 12 (12–14), *d* 11 (10–13), *e* 11 (11–13), *f* 11 (11–12), *h1* 10 (10–12), *h2* 14 (13–15).

*Idiosomal venter* (Fig. 7B) – All ventral setae smooth and pointed. Four pairs of aggenital and two pairs of genital setae; cupuli *ih* located anteriad *ag4*. Anal valves with two pairs of pseudanal setae. Two longitudinal groups of tiny sclerites situated between setae *4a* and *ag1*. Lengths of ventral setae: *1a* 22 (20–23), *1b* 19 (18–19), *1c* 19 (17–21), *2c* 20 (19–21), *3a* 21 (21–23), *3c* 19 (18–21), *4a* 19 (19–22), *4c* 18 (16–19), *ag1* 19 (18–21), *ag2* 16 (15–19), *ag3* 14

<figure><img src="image_14.png" /><figcaption>**Figure 7** *Neognathus sibiriensis* n. sp., female: A – idiosomal dorsum, B – idiosomal venter.</figcaption></figure>
<figure><img src="image_15.png" /><figcaption>**Figure 9** *Neognathus sibiriensis* n. sp., female: A-D – right legs I-IV respectively, dorsal aspect.</figcaption></figure>
<figure><img src="image_16.png" /><figcaption>**Figure 10** DIC micrographs of *Neognathus sibiriensis* n. sp., female: A – prodorsum and anterior part of hysterosoma, B – gnathosoma, dorsal aspect.</figcaption></figure>

leg setae smooth; setae *d* of tibia, (ft), (tc), (*p*) and *vs* of tarsus eupathid-like, blunt-tipped, with tiny subapical projections; other leg setae pointed; solenidion ω1 7 (6–7) digitiform, solenidion ω2 11 (10–11) baculiform and curved, solenidion φ 5 (4–5) digitiform, solenidion φρ 8 (7–8) baculiform and curved, seta *k* 4 (3–4). Leg II (Fig. 9B). Leg setation: Tr 1 (*v*'), Fe 3 (*d*, *l'*, *bv''*), Ge 6 (*d*, *l'*, *l''*, *v'*, *v''*, *k*), Ti 5(1) (*dζ*, *l'*, *l''*, *v'*, *v''*, φρ), Ta 9(2) (*ft'*, *tc'ζ*, *tc''ζ*, *a'*, *a''*, *u'*, *u''*, *pv*, *vs*, ω1, ω2). All leg setae smooth; setae *d* of tibia and (tc) of tarsus eupathid-like, blunt-tipped, with tiny subapical projections; other leg setae pointed; solenidion ω1 6 (6–7) digitiform, solenidion ω2 8 (8–9) baculiform and curved, solenidion φρ 7 (7) baculiform, seta *k* 3 (3). Leg III (Fig. 9C). Leg setation: Tr 2 (*l'*, *v*'), Fe 2 (*d*, *ev*'), Ge 2 (*d*, *v*'), Ti 4(1) (*d*, *l''*, *v*, *v''*, φρ), Ta 8(1) (*tc'*, *tc''*, *a'*, *a''*, *u'*, *u''*, *pv*, *vs*, ω). Solenidion ω 9 (9) digitiform, solenidion φρ 6 (6–7) baculiform. All leg setae smooth and pointed. Seta *l''* of genu absent. Leg IV (Fig. 9D). Leg setation: Tr 1 (*v*'), Fe 2 (*d*, *ev*'), Ge 3 (*d*, *l''*, *v*'), Ti 4(1) (*d*, *l''*, *v'*, *v''*, φρ), Ta 8 (*tc'*, *tc''*, *a'*, *a''*, *u'*, *u''*, *pv*, *vs*). Solenidion φρ 8 (7–8) baculiform. All leg setae smooth and pointed. Solenidion ω on tarsus absent.

**Deutonymph** (Fig. 11) — Length of idiosoma 220, width 125.

*Idiosomal dorsum* as in female. Lengths of dorsal setae: *vi* 11, *ve* 12, *sci* 11-, *sce* 11, *c1* 11, *c2* 10, *d* 10, *e* 11, *f* 11, *h1* 11, *h2* 12.

*Idiosomal venter* (Fig. 11) – similar with that of female, except absence of genital opening and setae *ag3*, *ag4*, *g1* and *g2*. Lengths of ventral setae: *la* 18, *lb* 16, *lc* 15, *2c* 16, *3a* 17, *3c* 16, *4a* 18, *ag1* 16, *ag2* 14, *ps1* 11, *ps2* 9.

*Gnathosoma* – as in female, except absence of setae *n*. Width of stylophore 36, lengths of setae: *m* 31, *or1* 11, *or2* 11, length of palptarsal solenidion ω 4.

*Legs* – as in female. Lengths of legs: I 150, II 115, III 110, IV 135. Solenidia: ωII 7, ω2I 8, φI 4, φpI 8, ωII 6, ω2II 7, φpII 6, ωIII 8, φpIII 6, φpIV 6; setae *k1* 3, *k1I* 3.

**Type material**

Female holotype, slide ZISP T-Cal-04, Russia, Tyumen Region, vicinity of lake Kuchak, 57°20'00.5"N 66°03'01.4"E, 23 September 2021, in sandy soil, coll. A.A. Khaustov. Paratypes: 35 females, 1 deutonymph, same data.
<figure><img src="image_17.png" /><figcaption>**Figure 11** *Neognathus sibiriensis* n. sp., deutonymph: opisthosomal venter.</figcaption></figure>

**Type deposition**

The holotype and four female paratypes of the new species are deposited in the acarological
collection of the Zoological Institute of RAS, St. Petersburg, Russia; other paratypes are
deposited in the mite collection of the Tyumen State University Museum of Zoology, Tyumen,
Russia.

**Etymology**

The name of the new species refers to its distribution in Siberia.

**Differential diagnosis**

The female of the new species is most similar to *Neognathus terrestris* in having large palptibial
claw, absence of solenidion ω on tarsus IV, absence of lateral projections on stylophore,
presence of two pairs of pseudanal setae, presence of well-developed cupuli *ia*, presence of
three setae on femur I, presence of seta *k* on genu II and presence of seta vs on tarsi III and
IV. The new species differs from *N. terrestris* by the presence of two setae on genu III (three
in *N. terrestris*), by the presence of solenidion φρ on tibia IV (absent in *N. terrestris*), and
presence of only one seta on palpgenu (two in *N. terrestris*). The new species is also similar
to *N. pusillus* by the absence of solenidion ω on tarsus IV, absence of lateral projections on
stylophore, presence of two pairs of pseudanal setae, presence of well-developed cupuli *ia*,
presence of three setae on femur I, presence of seta *k* on genu II, presence of solenidion φρ on
tibia IV, and presence of seta vs on tarsi III and IV. The new species differs from *N. pusillus* in having well-developed palptibial claw (very small in *N. pusillus*), by the presence of two setae on genu III (three in *N. pusillus*), and by the presence of only one seta on palpgenu (two in *N. pusillus*).

## Acknowledgements

The author thanks Mr. Latyntsev, R.V. (Tyumen State University, Tyumen, Russia) for the logistics. The present research was supported by the Russian Science Foundation, grant No. 20-64-47015.

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