Entomobryoides gruati Mehrafrooz Mayvan & Kováč sp. nov.

(Figs 1D, 2–5, Table 1)

Type locality. TURKMENISTAN, Lebap Province, Koytendag District, v. Gurshun Magdanly (=Svintsovyi rudnik), Kattakamov Cave, Coordinates: 37°51'30.92"N, 66°29'12.37"E, 1240 m a.s.l.

Type material. Holotype: female on slide [KaEn101Tu], dark zone, hand collecting on rotten wood, 18.v.2023, leg. J. Lips. Paratype: 13 specimens on slides [KaEn102Tu- KaEn114Tu], ibidem, 18.v.2023, 18.iv.2024 and 20.iv.2024, leg. J. Lips. Holotype and paratypes deposited in CoPJSU.

Description. Body length (excluding antennae) 2.48 mm (n=14), up to 2.8 mm in holotype. Ground colour pale brown, antennae with bluish pigment, dorsal side of head paler in lateral parts than the body; coxa pale brown but other part of legs pale blue; eye spots black.

Head. Eight eyes, GH smaller in size to EF (Fig. 2A). Antenna longer than head, without apical bulb and scales. Antennae 1.71 times the length of the head, relative length of Ant I:II:III:IV in holotype as 1:2.67:2.25:3.60; Ant IV without apical vesicle (as characteristic remark for the genus), and pin seta bifurcate (Fig. 2B); subapical organite small and rod-shape, accompanied with a small sensillum only a little bigger; Ant III with sensory organ formed by 2 long-ovoidal sensilla and 4 additional guards sensilla (Fig. 2C); Labrum with 4 smooth prelabral setae and 3 rows of 5, 5 and 4 smooth setae; labral papillae very small, with a minute terminal projection (Fig. 4B). Maxillary palp with 1 apical appendage and 1 subapical seta, with three sublobal hairs (Fig. 4C). Head ventrally with 7 anterior smooth setae and other setae ciliated, setal pattern as in figure 2D. Labium setal pattern formed by 5 smooth setae (a 1 –a 5) in anterior row; basal row with 7 smooth setae as m 1, m 2, r 1, r 2 e, l 1 and l 2 (Fig. 3C) with m 2, r 1 and r 2 somewhat smaller than other setae. Labial palp as in figure 3B, with 5 main papillae (A–E) with 0, 5, 0, 4, 4 guard setae respectively; lateral process (l.p.) of labial papilla E surpassing their papilla apex. Right mandible with 4 teeth and left mandible with 5 teeth.

Body. Abd IV:III length ratio in holotype = 4. Trochanteral organ with approximately 29–33 setae (Fig. 4D). Tibiotarsus not sub-segmented, with a double row of apressed ciliated setae on all tibiotarsi. Claw (Fig. 5B) with 4 inner teeth: paired at 50–54% (one of them larger and forward), first unpaired at 70% from basis, and the last one closer than 90%; dorsal teeth present and at the level of lateral teeth. Empodium lanceolate, with serrated external lamella. Tenent hair is clavate, similar in length to the claw. Length of manubrium and dens in holotype as 0.47 and 0.52 mm, respectively. Manubrial plate with 5 setae and 2 pseudopores (Fig. 4E). Mucro with apical tooth slightly larger than subapical one, mucronal spine reaching the tip of the subapical tooth; not crenulated dental area about 2 times of the length of mucro (Fig. 5C). Simplified Mc formula: 4-1-0-3-1/4-7/2-4/0-2-1/0-2-1-2-2.

Chaetotaxy of head. Setal pattern of dorsal side of head as in figure 2A. H1 area with 3 Mc (An 2, An 3a1, and An 3 and an additional seta); H2 area with one Mc (A 5); H4 area with 3 Mc (S 1, S 3, and S 4i); H4’ area with 3 Mc (S 4, S 5, and S 5i); H5 area only with Ps2 Mc.

Chaetotaxy of mesothorax. Dorsal setal pattern as in figure 3A. Area T1 with 4 Mc (m 1, m 2, m 2i and m 2i2); T2 with 7 Mc (a 5, m 4, m 4i, m 4p, m 4pi, m 4pe, and m 5).

Chaetotaxy of abdomen. Dorsal setal pattern as in figure 4A & 5A. Abd I with 7 Mc, and with sensilla acc in two different positions, Abd II area A1 with 2 Mc (a 2 and a 3), area A2 with 4 Mc (m3, m3ep, m3e, and m3ea); setae ‘as’ and ‘acc’ present; Abd III with Mc on A3 absent, area A4 with 2 Mc (a 2 and a 3) and one Mc on A5 (m 3), ‘acc’ between m 6 and p 6, ‘ms’ interior; Abd IV with Mc on A6 area absent, 2 Mc on A7 (A 3 and B 3), A8 with one Mc (B 4), 2 Mc on A9 (B 5 and A 5), A10 with two Mc (A 6 and B 6); sensillar formula as 2,2/2,2,2,12–13,3; microsensillar formula: 1,0/1,0,1.

Etymology. The species is dedicated to Jean-Pierre Gruat, who played a major role in organizing the biospeleological expeditions to Turkmenistan. His continuous enthusiasm, time, and efforts were crucial in making these explorations possible.

Affinity to subterranean habitats. Specimens of E. gruati sp. nov. were found to inhabit a dark zone of the Kattakamov Cave that represents in fact a complex of interconnected mining galleries artificially created in several levels inside the karst massif. The new species has full set of dark pigmented eyes, reduced body pigment and does not show any clearly troglomorphic character. Thus, it could be assigned to category of eutroglophiles, i.e. animals not strictly associated with subterranean habitats, but able to reproduce there.

Remarks. So far, 12 species of the genus Entomobryoides have been described worldwide (Bellinger et al. 1996 –2025). In terms of dorsal macrochaetotaxy, the new species shows its closest resemblance to E. dagestanicus Jordana & Baquero, 2021, E. guthriei (Mills, 1931) and E. kalakaua Carpenter, 1904. Among these species, E. kalakaua differs from the E. gruati sp. nov. by 3 Mc in the H1 and 2 Mc in the H5 areas on dorsal side of head, whereas the new species has 4 Mc in H1 and only a single Mc (Ps2) in H5 tergite area. Entomobryoides guthriei can be distinguished from the new species by 2 Mc in H5 area, whereas the new species has only 1 Mc in this area. In addition, E. guthriei shows 4 Mc in the T2 area of Th II, while the new species has 7 Mc in the same area. Moreover, in E. guthriei, Mc in the A9 area of Abd IV are absent, in contrast to the new species, which has 2 Mc in this area (A 5 and B 5). Also, E. dagestanicus differs from the E. gruati sp. nov. in 7 Mc in the T2 area of Th II, while the new species has 6 Mc there. In the A8 and A9 areas of Abd IV, E. dagestanicus has 2 (A 4 and B 4) and 1 (B 5) Mc, respectively, whereas the new species has 1 (B 4) and 2 (A 5 and B 5) Mc in these areas.