1✉ Tyumen State University, Tyumen, Volodarskogo 6, 625003 Russia.
2022 - Volume: 62 Issue: 1 pages: 99-112
https://doi.org/10.24349/1dwx-x5h2The 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 palpfemur (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.
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 an AxioImager A2 compound microscope (Carl Zeiss, Germany) with phase-contrast and differential interference contrast (DIC) illumination. Photomicrographs were taken with an AxioCam ICc5 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.
Type species: Molothrognathus leptostylus Summers and Schlinger, 1955, by original designation
ZOOBANK: 111B34FE-B677-4708-865C-45AAC830DD79
(Figures 1–6)
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.
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, acmϛ, ul'ϛ, ul″ϛ, sulϛ, ω); tibial claw large, slightly hooked; all palpal setae smooth, eupathidia acmϛ, ul'ϛ, ul″ϛ, sulϛ 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 (v′), Fe 2 (d, bv″), Ge 6 (d, l', l″, v′, v″, k), Ti 5(2) (d, l', l″, v′, v″, φ, φp), Ta 16(1) (ft′, ft″, tc′ϛ, tc″ϛ, p′ϛ, p″ϛ, 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 φp 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″ϛ 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 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 ωI 7, φ 2, φp 6-7, ωII 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 ωI 7, φ 2, φp 8, ωII 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 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: 1a 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 ωI 6, φ 2, φp 5‒6, ωII 3, seta k 4. Leg IV without setae v′ of trochanter, d of femur and genu and it′ of tarsus.
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.
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 deposited in the mite collection of the Tyumen State University Museum of Zoology, Tyumen, Russia.
The name of the new species refers to geographical distribution in Altai.
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 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).
Type species: Neognathus insolitus Willmann, 1952, by original designation
ZOOBANK: 14E92361-B739-49CB-874B-2603EC02F309
(Figures 7–11)
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.
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 (14‒16), ag4 12 (12‒14), g1 17 (17‒18), g2 16 (16‒18), ps1 11 (11‒13), ps2 12 (12‒13).
Gnathosoma (Figs 8, 10B) ‒ Stylophore width 40 (40‒43); peritremes with four pairs of segments (Figs 8A, 10B); cheliceral stylets long, slightly curved; cheliceral levers poorly visible, about four times shorter than cheliceral stylets. Palpal supracoxal setae (ep) short, peg-like; palpal chaetotaxy: Tr 0, Fe 1 (d), Ge 1 (d), Ti 3 (d, l', l″), Ta 8(1) (ba, bp, lp, va, acmϛ, ul'ϛ, ul″ϛ, sulϛ, ω); tibial claw well developed, slightly hooked; all palpal setae smooth, eupathidia acmϛ, ul'ϛ, ul″ϛ, sulϛ blunt-tipped, other palpal setae pointed. Subcapitulum with delicate striae in basal part; all subcapitular setae smooth and pointed; lengths of subcapitular setae: m 20 (19‒23), n 35 (32‒35), or1 13 (11‒13), or2 13 (12‒14), length of palptarsal solenidion ω 4 (3‒4).
Legs (Fig. 9) ‒ Lengths of legs: I 175 (175), II 130 (130‒135), III 135 (130‒135), IV 170 (160‒170). Leg I (Fig. 9A). Leg setation: Tr 1 (v′), Fe 3 (d, l', bv″), Ge 6 (d, l', l″, v′, v″, k), Ti 5(2) (dϛ, l', l″, v′, v″, φ, φp), Ta 14(2) (ft′ϛ, ft″ϛ, tc′ϛ, tc″ϛ, p′ϛ, p″ϛ, a′, a″, u′, u″, vsϛ, pv′, pl', pl″, ω1, ω2). Supracoxal seta of leg I (el) peg-like; seta k of genu situated in shallow depression; all 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 φp 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) (dϛ, l', l″, v′, v″, φp), Ta 9(2) (ft′, tc′ϛ, tc″ϛ, 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 φp 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″, φp), Ta 8(1) (tc′, tc″, a′, a″, u′, u″, pv, vs, ω). Solenidion ω 9 (9) digitiform, solenidion φp 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″, φp), Ta 8 (tc′, tc″, a′, a″, u′, u″, pv, vs). Solenidion φp 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: 1a 18, 1b 16, 1c 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: ω1I 7, ω2I 8, φI 4, φpI 8, ω1II 6, ω2II 7, φpII 6, ωIII 8, φpIII 6, φpIV 6; setae kI 3, kII 3.
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.
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.
The name of the new species refers to its distribution in Siberia.
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 φp 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 φp 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).
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.