1✉ Tyumen State University, Tyumen, Volodarskogo 6, 625003 Russia.
2021 - Volume: 61 Issue: 4 pages: 910-927
https://doi.org/10.24349/DZRV-GIdYThe 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). The caligonellid mites of Crimea are poorly studied. Previously only one species, Molothrognathus dilucidus Kuznetsov was described from Crimea (Kuznetsov 1978).
The genus Caligonella Berlese, 1910 comprises 11 described species: C. afroensis Smith Meyer and Ueckermann, 1989, C. claviparma Smith Meyer and Ueckermann, 1989, C. geonoma Smith Meyer and Ueckermann, 1989, C. scutovata Smith Meyer and Ueckermann, 1989 (all from South Africa), C. humilis (C.L. Koch, 1838) (Holarctic region), C. haddadi Bagheri, Maleki and Changizi, 2013 (Iran, Turkey), C. saboorii Hoseini, Khanjani and Javadi Khaderi, 2014, C. astragalusi Pishehvar and Khanjani, 2020 (Iran), C. tunica Fan, 2000, C. tunxiensis Hu and Hu, 1997 (both from China), and C. urhani Akyol, 2018 (Turkey) (Akyol 2018; Beron 2020; Doğan and Doğan 2020; Pishehvar and Khanjani 2020). Pishehvar and Khanjani (2020) provided the latest key to species of Caligonella.
The genus Molothrognathus Summers and Schlinger, 1955 comprises 28 described species: M. azizi Ueckermann and Khanjani, 2003, M. kurdistaniensis Amini, Khanjani and Khanjani, 2018, M. mehrnejadi Liang and Zhang, 1997, M. mikaeeleli Bagheri and Ahaniazad, 2012, M. paratunipalpus Bagheri, Maleki and Changizi, 2013, M. seusius Soliman and Gomaa, 1980 (all from Iran), M. bahariensis Ueckermann and Khanjani, 2003, M. shirazicus Khanjani, Bakhshi and Khanjani, 2016 (Iran, Turkey), M. brasiliensis Silva, Brentino and Ferla, 2017 (Brazil), M. citrivallis Smith Meyer and Ueckermann, 1989, M. flatichelus Smith Meyer and Ueckermann, 1989, M. parmatus Smith Meyer and Ueckermann, 1989 (all from South Africa), M. colei Swift, 1996, M. conantae Swift, 1996 (both from Hawaii), M. fulgidus Summers and Schlinger, 1955, M. washingtonia McGregor, 1959 (all from USA), M. crucis Summers and Schlinger, 1955 (USA, Turkey), M. dilucidus Kuznetsov, 1978 (Crimea), M. kamili Doğan, 2003 (Turkey, Iran), M. leptostylus Summers and Schlinger, 1955 (USA, Canada, India, Pakistan), M. minutus Soliman, 1972 (Egypt, Iran), M. phytocolus Smith Meyer and Ueckermann, 1989 (South Africa, Iran, Turkey, Yemen), M. rosei Smiley and Moser, 1968 (Mexico), M. seelyae (Andre, 1996) (Namibia), M. terrulentus Smith Meyer and Ueckermann, 1989 (South Africa, Iran, Turkey), M. tunipalpus Smith Meyer and Ueckermann, 1989 (South Africa, Iran), M. venustus (Khaustov and Kuznetsov, 1997) (Ukraine, Turkey), and M. saudiensis Halawa, 2013 (Saudi Arabia) (Halawa 2013; Beron 2020).
During the study of soil predatory mites, two new species, Caligonella quinqueocellata n. sp. and Molothrognathus tauricus n. sp. were collected from moss on the sandy soil in northern part of Crimea. Both species were collected from the same sample. The aim of this paper is to describe and illustrate these new species.
Mites were collected from the soil samples by Berlese 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: Stigmaeus humilis C.L. Koch, 1838, by original designation
ZOOBANK: 3FE8CEF5-57DF-4523-BF9A-9F15AE42AA02
(Figures 1–8)
Diagnosis — Female. Dorsal shield present, seta ve located on soft cuticle; prodorsum with five pairs of ocelli; one pair of pseudanal setae; ventral plate absent.
Description
Female (Figs 1-5) — Length of idiosoma 460 (405), width 275 (255).
Idiosomal dorsum (Figs 1A, 3A, 5B, C) ‒ Ovate. Dorsal idiosomal stria thick, usually double; dorsal shield well developed, ovate, with few sparsely distributed puncta and fine stria (Fig. 5C) and located in space between setae vi, ve, and c1, its length 135 (130), width 68 (58). Five pairs of ocelli located posterolaterad setae sci, anterior ocellus much bigger than four posterior (Figs 3A, 5B). Cupuli ia, im and ip very large, almost round; ia located just posteriad ocelli, im posterolaterad c1 and ip laterad f. All dorsal idiosomal setae subequal, short, smooth and indistinctly blunt-tipped. Anal valves located dorsoterminal, weakly striated and with few sparsely distributed puncta; one pair of pseudanal setae. Lengths of dorsal setae: vi 17 (17), ve 17 (17), sci 20 (19), sce 21 (18), c1 16 (15), c2 18 (15), d 18 (15), e 17 (14), f 15 (13), h1 15 (12), h2 16, ps 15 (12).
Idiosomal venter (Figs 1B, 5D) ‒ Ventral idiosoma without plate between coxae, striated. Coxal fields I-II and III-IV with sparsely distributed puncta; coxal field IV with posterior plate-like projection delineated by stria and sparsely distributed puncta. All ventral setae smooth and pointed. Three pairs of aggenital and one pair of genital setae (Fig. 5D); cupuli ih located anterolaterad ag3. Lengths of ventral setae: 1a 27 (26), 1b 28 (26), 1c 17 (17), 2c 15 (13), 3a 25 (26), 3b 17 (13), 4a 20 (19), 4c 20 (16), ag1 18 (18), ag2 16 (12), ag3 14 (12), g 12 (11).
Gnathosoma (Figs 2, 3B, C, 5A) ‒ Stylophore almost oval (Fig. 2 A), distinctly punctate in anterior 2/3 and finely striated in posterior 1/3 parts, its length 110 (100), width 91 (75); peritremes distinctly curved in central part of stylophore (Figs 2A, 3B, 5A); cheliceral levers large, oval, almost as long as cheliceral stylets (Fig. 5C). 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 well developed, slightly hooked; all palpal setae smooth, eupathidia acmϛ, ul'ϛ, ul''ϛ, sulϛ with slightly swollen tips, other palpal setae pointed. Subcapitulum with few sparsely distributed puncta (Fig. 2B); all subcapitular setae smooth, setae m pointed, adoral setae weakly blunt-tipped; lengths of subcapitular setae: m 33, or1 6, or2 8, length of palptarsal solenidion ω 4 (3).
Legs (Fig. 4) ‒ Lengths of legs (excluding claws): I 300 (280), II 230 (210), III 250 (220), IV 295 (250). Leg I (Fig. 4A) 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 located in deep depression; all leg setae smooth; setae (tc) and (p) eupathid-like, blunt-tipped, other leg setae pointed; solenidion ω 8 (7) digitiform, solenidia φ 4 (4) and φp 12 (12) baculiform. Leg II (Fig. 4B). Leg setation: Tr 1 (v'), Fe 2 (d, bv''), Ge 5 (d, l', l'', v', v''), Ti 5 (d, l', l'', v', v''), Ta 11(1) (ft', tc', tc'', p''ϛ, it'', a', a'', u', u'', pv', pv'', ω). All leg setae smooth; seta p''ϛ eupathid-like, blunt-tipped; other leg setae pointed; solenidion ω 7 (7) digitiform. Leg III (Fig. 4C). 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. 4D). 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.
Larva (Figs 6-8) — Length of idiosoma 245, width 170.
Idiosomal dorsum (Fig. 6A) ‒ completely striated, without dorsal shield. Dorsal setae and cupuli as in female. With one pair of large anterior ocelli, posterior ocelli indistinct. Anal opening terminal. Lengths of dorsal setae: vi 11, ve 10, sci 11, sce 12, c1 10, c2 10, d 9, e 10, f 11, h1 13, h2 11, ps 7.
Idiosomal venter (Fig. 6B) ‒ Ventral idiosoma completely striated. Coxal field I with two setae (1a, 1b), coxal field III with one setae (3a); genital and aggenital setae absent. All ventral setae smooth and pointed; cupuli ih located anteromesad h2. Lengths of ventral setae: 1a 19, 1b 15, 3a 16.
Gnathosoma (Fig. 7) ‒ in general similar to that of female except following: peritremes straight, subcapitulum without setae m, palptarsus with setae acm and sul simple (not eupathidia). Length of stylophore 56, width 53, lengths of setae: or1 6, or2 7, length of palptarsal solenidion ω 3.
Legs (Fig. 8) ‒ Lengths of legs: I 170, II 130, III 145. Leg I (Fig. 8A) longer than other legs. Leg setation: Tr 0, Fe 2 (d, bv''), Ge 5 (l', l'', v', v'', k), Ti 5(2) (d, l', l'', v', v'', φ, φp), Ta 15(1) (ft', ft'', tc', tc'', p'ϛ, p''ϛ, a', a'', u', u'', vs, pv', pv'', pl', pl'', ω). Seta k of genu located in shallow depression; all leg setae smooth; setae (p) eupathid-like, blunt-tipped, other leg setae pointed; solenidion ω 7 digitiform, solenidia φ 3 and φp 7 baculiform. Leg II (Fig. 8B). Leg setation: Tr 0, Fe 2 (d, bv''), Ge 4 (l', l'', v', v''), Ti 5 (d, l', l'', v', v''), Ta 10(1) (ft', tc', tc'', p''ϛ, a', a'', u', u'', pv', pv'', ω). All leg setae smooth; seta p''ϛ eupathid-like, blunt-tipped; other leg setae pointed; solenidion ω 6 digitiform. Leg III (Fig. 8C). Leg setation: Tr 0, Fe 2 (d, ev'), Ge 1 (v'), Ti 4 (d, l'', v', v''), Ta 8 (tc', tc'', a', a'', u', u'', pv', pv''). All leg setae smooth and pointed.
Type material — Female holotype, slide ZISP T-Cal-01, Crimea, Arabat Spit, 45°17'54.0''N 35°28'19.0''E, 14 June 2021, moss on sandy soil, coll. A.A. Khaustov. Paratypes: 1 female, 1 larva, same data.
Type deposition — The holotype of the new species is 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.
Etymology — The name of the new species is combined from two Latin words quinque meaning five and ocellus and refers to presence of five pairs of ocelli in female.
Differential diagnosis — The new species differs from all species of Caligonella in having five pairs of ocelli on prodorsum (only two in other species), The new species is most similar to Caligonella scutovata Smith-Meyer and Ueckermann described from South Africa (Smith-Meyer and Ueckermann 1989), by the presence of dorsal idiosomal shield and in having one pair of pseudanal setae. The new species differs from C. scutovata by the absence of ventral plate between coxae (present in C. scutovata) and location of setae ve on soft cuticle (ve located on dorsal shield in C. scutovata).
Type species: Molothrognathus leptostylus Summers and Schlinger, 1955, by original designation
ZOOBANK: 1A3D7D07-6A22-4AB1-BD09-E44266190FC1
(Figures 9–15)
Diagnosis — Female. Dorsal shield present in space between setae vi, ve and c1; setae sce distinctly longer than other dorsal setae; setae c2 much shorter than sce and subequal with ve; setae ag3 absent.
Description
Female (Figs 9-11) — Length of idiosoma 320, width 185.
Idiosomal dorsum (Fig. 9A) ‒ Ovate. Dorsal idiosomal stria thin, usually double; dorsal shield present, smooth, weakly sclerotized, ovate, and located in space between setae vi, ve, and c1. Two pairs of ocelli located posterolaterad setae sci, posterior ocellus poorly visible. Cupuli ia, im and ip large, almost round; ia located just posteriad ocelli, im anterolaterad d and ip laterad f. All dorsal idiosomal setae smooth and pointed; sce distinctly longer than other dorsal setae; setae ve, sci and c2 subequal, c1 slightly shorter than c2. Anal valves located dorsal; two pairs of pseudanal setae. Lengths of dorsal setae: vi 22, ve 18, sci 21, sce 44, c1 14, c2 20, d 16, e 20, f 19, h1 27, h2 26, ps1 7, ps2 10.
Idiosomal venter (Fig. 9B) ‒ Ventral idiosoma without plate between coxae, striated. Coxal fields I-II and III-IV smooth. All ventral setae smooth and pointed. Two pairs of aggenital and one pair of genital setae; cupuli ih located posterolaterad ag2. Lengths of ventral setae: 1a 30, 1b 25, 1c 26, 2c 23, 3a 37, 3b 23, 4a 27, 4c 21, ag1 25, ag2 17, g 15.
Gnathosoma (Fig. 10) ‒ Stylophore almost triangular (Fig. 10A), split distally, longitudinally striated, its length 82, width 46; peritremes tubular, typical for the genus; cheliceral stylets long, about three times longer than cheliceral levers. Palpal supracoxal setae (ep) located in deep depression with terminal pore; palpal chaetotaxy as in Caligonella quinqueocellata; 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 few sparsely distributed puncta (Fig. 10B); all subcapitular setae smooth and pointed; lengths of subcapitular setae: m 35, or1 8, or2 9, length of palptarsal solenidion ω 5.
Legs (Fig. 11) ‒ Lengths of legs: I 205, II 150, III 170, IV 200. Setation of legs as in Caligonella quinqueocellata. Leg I (Fig. 11A) longer than other legs. Supracoxal seta of leg I (el) located in deep depression with terminal pore; seta k of genu located in shallow depression; all leg setae smooth; setae (tc) and (p) eupathid-like, blunt-tipped, other leg setae pointed; solenidion ω 10 digitiform, solenidia φ 3 and φp 7 baculiform. Leg II (Fig. 11B). All leg setae smooth; seta p''ϛ eupathid-like, blunt-tipped; other leg setae pointed; solenidion ω 4 digitiform. Leg III (Fig. 11C). All leg setae smooth and pointed. Leg IV (Fig. 11D). All leg setae smooth and pointed.
Protonymph (Figs 12, 14C) — Length of idiosoma 250‒275, width 155‒160.
Idiosomal dorsum (Fig. 12A) ‒ completely striated, without distinct dorsal shield, with oval area with very thin stria anteriad c1. Dorsal setae and cupuli as in female. Anal opening terminal. Lengths of dorsal setae: vi 18, ve 17, sci 17, sce 46, c1 15, c2 19, d 17, e 18, f 20, h1 33, h2 35, ps1 8, ps2 8.
Idiosomal venter (Fig. 12B) ‒ Ventral idiosoma completely striated. Coxal field I‒III as in female; coxal fields IV without setae; one pair of aggenital setae. All ventral setae smooth and pointed; cupuli ih located anteriad h2. Lengths of ventral setae: 1a 24, 1b 22, 1c 22, 2c 17, 3a 34, 3b 17, ag 18.
Gnathosoma ‒ as in female. Length of stylophore 69, width 40, lengths of setae: m 24, or1 7, or2 7, length of palptarsal solenidion ω 4.
Legs (Fig. 14C) ‒ Lengths of legs: I 175, II 130, III 150, IV 165. Setation of legs I‒III as in female. Leg I longer than other legs. Solenidion ω 8 digitiform, solenidia φ 3 and φp 6 baculiform. Leg II. Solenidion ω 4 digitiform. Leg IV (Fig. 14C). Leg setation: Tr 0, Fe 1 (ev'), Ge 1 (v'), Ti 4 (d, l'', v', v''), Ta 8 (tc', tc'', a', a'', u', u'', pv', pv''). All leg setae smooth and pointed.
Larva (Figs 13, 14A, B, 15) — Length of idiosoma 235, width 135.
Idiosomal dorsum (Fig. 13A) ‒ completely striated, without dorsal shield. Dorsal setae c2 much longer than in female and protonymph. Anal opening terminal. Lengths of dorsal setae: vi 21, ve 17, sci 19, sce 78, c1 20, c2 57, d 17, e 25, f 38, h1 49, h2 35, ps1 7, ps2 8.
Idiosomal venter (Fig. 13B) ‒ Ventral idiosoma similar with that of protonymph, except absence of setae 2c, 3b and ag1. Lengths of ventral setae: 1a 25, 1b 26, 3a 35.
Gnathosoma (Fig. 14A, B) ‒ in general similar to that of female except following: subcapitulum without setae m (Fig. 14A), palptarsus with setae acm and sul simple (not eupathidia) (Fig. 14B). Length of stylophore 60, width 33, lengths of setae: or1 7, or2 8, length of palptarsal solenidion ω 3.
Legs (Fig. 15) ‒ Lengths of legs: I 165, II 125, III 145. Setation of legs as in larva of Caligonella quinqueocellata, except absence of seta p'' on tarsus II. Leg I (Fig. 15A) longer than other legs. All leg setae smooth; setae (p) eupathid-like, blunt-tipped, other leg setae pointed; solenidion ω 7 digitiform, solenidia φ 3 and φp 6 baculiform. Leg II (Fig. 15B). All leg setae smooth and pointed; solenidion ω 5 digitiform. Leg III (Fig. 15C). All leg setae smooth and pointed.
Type material — Female holotype, slide ZISP T-Cal-02, Crimea, Aeabat Spit, 45°17'54.0''N 35°28'19.0''E, 14 June 2021, moss on sandy soil, coll. A.A. Khaustov. Paratypes: 1 larva, 2 protonymphs, same data.
Type deposition — The holotype and 2 protonymph paratypes of the new species are deposited in the acarological collection of the Zoological Institute of RAS, St. Petersburg, Russia; other paratype is 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 Crimea.
Differential diagnosis — The female of the new species is most similar to Molothrognatus crucis Summers and Schlinger, 1955, described from USA (Summers and Schlinger 1955) and redescribed from Turkey (Doğan 2003), and M. mikaeeli Bagheri and Ahamazad, 2012, described from Iran (Ahanazad and Bagheri 2012), by the absence of setae ag3, and setae c2 subequal with c1 and ve and distinctly shorter than sce. The new species differs from M. mikaeeli by the presence of dorsal idiosomal shield (absent in M. mikaeeli). The new species differs from M. crucis in having dorsal idiosomal shield much shorter, its posterior margin not exceeding beyond bases of setae c1 and oval in shape (dorsal idiosomal shield very long, tongue-shaped, its posterior margin exceeding beyond bases of setae d in M. crucis) and by distinctly shorter setae sce, which about twice longer than c2 (sce much longer, about three times longer than c2 in M. crucis). The female of the new species is also similar to M. shirazicus Khanjani, Bakhshi and Khanjani, 2016, described from Iran (Khanjani et al. 2016) and M. colei Swift, 1996, described from Hawaii (Swift 1996), by the similar shape of dorsal idiosomal shield. The new species differs from both species by the absence of setae ag3 (present in M. shirazicus and M. colei). The new species differs from M. shirazicus in having setae c2 subequal with ve and sci (c2 distinctly longer than ve and sci in M. shirazicus). The new species differs from M. colei in having setae c2 twice shorter than sce (c2 and sce subequal in M. colei).
The genera Caligonella and Molothrognathus are the most derived group of Caligonellidae (Fan 2000) and very similar morphologically. The only difference between genera is position of anterior end of peritremes. In Caligonella anterior end of peritremes situated anteroventrally and in Molothrognathus dorsomedially on stylophore. The discovery of larval stages of Caligonella quinqueocellata and Molothrognathus tauricus and description of their legs shows more derived leg setation in comparison to more primitive genus Coptocheles (Swift 2001). The only difference between larval legs setation in Caligonella quinqueocellata and Molothrognathus tauricus is the absence of seta p'' on tarsus II in M. tauricus. The chaetotaxy of palptarsus in larval stage of Caligonellidae has never been described. In both described species, palptarsus of larva has the same number of setae as adults. However, setae acm and sul are not modified (not eupathid-like). In contrast to more early derivative genus Neognathus, palptarsus of Caligonella and Molothrognathus lacks seta lp.
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.