121 European Journal of Taxonomy 833: 121–142 ISSN 2118-9773 https://doi.org/10.5852/ejt.2022.833.1889 www.europeanjournaloftaxonomy.eu 2022 · Zhang Y.-H. et al. This work is licensed under a Creative Commons Attribution License (CC BY 4.0). R e s e a r c h a r t i c l e urn:lsid:zoobank.org:pub:C82A34E8-7A30-4581-8C14-269C178A66FD New species of genus Atractides Koch, 1837 (Acari: Hydrachnidiae, Hygrobatidae) from Qinghai, China Yu-Hao ZHANG 1,#, Hai-Tao LI 2,#, Cai-Yun LI 3 & Jian-Jun GUO 4,* 1,2,3,4 Institute of Entomology, Guizhou University, Scientific Observing and Experimental Station of Crop Pest in Guiyang, Ministry of Agriculture and Rural Affairs of the P.R. China, Guiyang 550025, P.R. China. * Corresponding author: jjguo@gzu.edu.cn 1 Email:1289568720@qq.com 2 Email: lhtzlp424666@outlook.com 3 Email: 1377195309@qq.com # Yu-Hao Zhang and Hai-Tao Li contributed equally to this study 1 urn:lsid:zoobank.org:author:9413E3A0-C9FB-4CCB-8F60-DE9454CF856D 2 urn:lsid:zoobank.org:author:5B5D8A0D-55B4-4EC7-A6B5-A3B4B7A8A475 3 urn:lsid:zoobank.org:author:5E4C3DC0-812D-4822-9B1F-119EEE651C4C 4 urn:lsid:zoobank.org:author:60680105-E469-4F51-AF3D-094BED1C361E Abstract. The paper deals with five new species of the genus Atractides Koch, 1837 (Acari: Hydrachnidiae, Hygrobatidae) collected from Qinghai Province, P.R. China, Atractides (Atractides) biprojectus Zhang, Li & Guo sp. nov., Atractides (Atractides) smiti Zhang, Li & Guo sp. nov., Atractides (Atractides) menyuanensis Zhang, Li & Guo sp. nov., Atractides (Atractides) longiprojectus Zhang, Li & Guo sp. nov. and Atractides (Atractides) xianmiensis Zhang, Li & Guo sp. nov. All the new species are described and illustrated in detail, and all the type specimens are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC). Keywords. Water mite, Atractides, new species, taxonomy, Qinghai-Tibet Plateau. Zhang Y.-H., Li H.-T., Li C.-Y. & Guo J.-J. 2022. New species of genus Atractides Koch, 1837 (Acari: Hydrachnidiae, Hygrobatidae) from Qinghai, China. European Journal of Taxonomy 833: 121–142. https://doi.org/10.5852/ejt.2022.833.1889 Introduction Atractides Koch, 1837 are reported in all biogeographical areas except for Australia and Antarctica (Cook 1974; Gerecke 2003). Most species are known from the northern Hemisphere, and only found in clean waters where the substratum is well preserved, so they are probably sensitive to many forms of human impact (Gerecke 2003; Pešić & Smit 2011; Gülle et al. 2015). https://doi.org/10.5852/ejt.2022.833.1889 http://www.europeanjournaloftaxonomy.eu/index.php/ejt/index https://creativecommons.org/licenses/by/4.0/ http://zoobank.org/urn:lsid:zoobank.org:pub:C82A34E8-7A30-4581-8C14-269C178A66FD https://orcid.org/0000-0002-0523-6704 mailto:jjguo@gzu.edu.cn mailto:jjguo@gzu.edu.cn mailto:jjguo@gzu.edu.cn mailto:jjguo@gzu.edu.cn mailto:jjguo@gzu.edu.cn mailto:1289568720@qq.com mailto:lhtzlp424666@outlook.com mailto:1377195309@qq.com http://zoobank.org/urn:lsid:zoobank.org:author:9413E3A0-C9FB-4CCB-8F60-DE9454CF856D http://zoobank.org/urn:lsid:zoobank.org:author:5B5D8A0D-55B4-4EC7-A6B5-A3B4B7A8A475 http://zoobank.org/urn:lsid:zoobank.org:author:5E4C3DC0-812D-4822-9B1F-119EEE651C4C http://zoobank.org/urn:lsid:zoobank.org:author:60680105-E469-4F51-AF3D-094BED1C361E https://doi.org/10.5852/ejt.2022.833.1889 European Journal of Taxonomy 833: 121–142 (2022) 122 Currently, the genus Atractides has four subgenera (Atractides Koch, 1837; Tympanomegapus Thor, 1923; Polymegapus K. Viets, 1926; Maderomegapus Lundblad, 1941), and about 405 species have been described from all over the world (K.O. Viets 1987; Gerecke 2003; Pešić et al. 2018; Pešić & Smit 2018, 2021a, 2021b; Smit 2020; Gülle et al. 2021; http://www.watermite.org/). Based on previous information, two subgenera and 18 species of Atractides have been reported for the Chinese fauna: Atractides s. str. with 14 species and Tympanomegapus Thor, 1923 with 4 species (Jin 1997; Yi et al. 2010; Wang & Jin 2012, 2013; Wang et al. 2015). The Qinghai Province lies in the west of China, on the Qinghai-Tibet Plateau. The Qinghai-Tibet Plateau is the highest and largest plateau in the world, which has a wide range of geological, topographical and climatic gradients. Therefore, there is a greater biodiversity than in the surrounding lowlands and other high elevation regions (Sun et al. 2014). Through a joint investigation of water mites in Qinghai Province, five new species are found: Atractides (Atractides) biprojectus Zhang, Li & Guo sp. nov., Atractides (Atractides) smiti Zhang, Li & Guo sp. nov., Atractides (Atractides) menyuanensis Zhang, Li & Guo sp. nov., Atractides (Atractides) longiprojectus Zhang, Li & Guo sp. nov. and Atractides (Atractides) xianmiensis Zhang, Li & Guo sp. nov. All the new species are described and illustrated in detail. Material and methods Specimens in this study were all collected by Hai-Tao Li from Qinghai Province, P.R. China. Water mites were collected by hand netting, sorted on the spot from the living material, preserved in Koenike’s fluid and dissected following Jin (1997) under a Motic SMZ-168 stereo microscope. Specimens were observed under a Nikon Ni-E microscope (with a Nikon DS-Ri2 camera). All illustrations were edited with Adobe Photoshop CC2018. All measurements are given in micrometers (μm) following Gerecke (2003). Terms are modified from Jin (1997) and Gerecke (2003). The following abbreviations are used: a.s.l. = above sea level A1 = preantennal glandularia A2 = postantennal glandularia Ac = acetabulum (pl. acetabula, numbered 1 to 3) ACG = anterior coxal group (Cx-I+Cx-II) Ap = acetabular plates C1–C4 = coxoglandularia 1–4 Cx-I–IV = coxae I–IV D1–D4 = dorsoglandularia 1–4 dL = dorsal length HB = central height IL = lateral length I-L-1–6, etc. = the first–sixth segment of the first leg, etc. L = length L1–L4 = lateroglandularia 1–4 mL = median length O1 = preocularia O2 = postocularia P-1–P-5 = the first–fifth segment of palp PCG = posterior coxal group (Cx-III+Cx-IV) http://www.watermite.org/ ZHANG Y.-H. et al., New species of Atractides from China 123 S-1 = proximal large ventral seta at I-L-5 S-2 = distal large ventral seta at I-L-5 So1–So5 = slit organs 1–5 V1–V4 = ventroglandularia 1–4 W = width Holotype and paratypes are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC). Results Class Arachnida Lamarck, 1801 Order Trombidiformes Reuter, 1909 Superfamily Hygrobatoidea Koch, 1842 Family Hygrobatidae Koch, 1842 Genus Atractides Koch, 1837 Subgenus Atractides Koch, 1837 Atractides (Atractides) biprojectus Zhang, Li & Guo sp. nov. urn:lsid:zoobank.org:act:06CA408F-1FC6-4FD0-AA2A-E94B784621C0 Figs 1–3 Diagnosis Male Dorsal muscle attachment unsclerotized. I-L-5 longish, S-1 and S-2 with blunt tips and with a narrow setal interspace between them; I-L-6 curved. Ac in an obtuse triangle, V1 separated from V2. P-2 and P-3 with a ventral projection respectively; P-4 divided by two long ventral hairs in sectors 2:3:1, sword seta between two ventral hair insertions and near the terminal. Female Similar to male. Ventral projection of P-2 not obvious, and P-3 ventral margin nearly straight. Etymology The Latin prefix ‘bi-’ means two, in the male of the new species P-2 and P-3 are with a ventral projection respectively. Type material Holotype CHINA • ♂; Qinghai Province, Huangnan Tibetan Autonomous Prefecture, Zeku County, Maixiu Town; 35°18′64′′ N, 101°52′32′′ E; 3201 m a.s.l.; 17 Jul. 2020; Hai-Tao Li leg.; running water; GUGC, Slide No. QH-HY-2020071701. Paratypes CHINA • 3 ♂♂; same collection data as for holotype; GUGC, Slides No. QH-HY-2020071702 to 2020071704 • 1 ♀; same collection data as for holotype; GUGC, Slide No. QH-HY-2020071705. Description Male (n = 4) Idiosoma oval; dorsal muscle attachment unsclerotized, O2 and D1 at the same level; setae of D1 and D2 longer than others, setae of D2 reaching to D3; all slit organs visible, So1 near the eye capsule and at http://zoobank.org/urn:lsid:zoobank.org:act:06CA408F-1FC6-4FD0-AA2A-E94B784621C0 European Journal of Taxonomy 833: 121–142 (2022) 124 Fig. 1. Atractides (Atractides) biprojectus Zhang, Li & Guo sp. nov. A–E. Holotype, ♂ (GUGC, Slide No. QH-HY-2020071701). F. Paratype, ♀ (GUGC, Slide No. QH-HY-2020071705). A. Idiosoma, dorsal view. B. Idiosoma, ventral view. C. Gnathosoma. D. Chelicera. E. Palp. F. Palp. Scale bars = 100 μm. ZHANG Y.-H. et al., New species of Atractides from China 125 the level of O1, So2 in front of L2, So3 near D2, So4 at the middle of D3 and L4; So5 behind D4 (Fig. 1A). ACG fused together and with a suture, PCG separated; apodemes from ACG not reaching to Cx-IV. Acetabula three pairs and in an obtuse triangle; V1 separated from V2; V3 and V4 forming a trapezoid, V4 at the same level as the middle of Ap (Fig. 1B). Palp five-segmented; P-2 and P-3 with a ventral projection respectively; P-4 with numerous dorsal hairs, and divided by two long ventral hairs in sectors 2:3:1, sword seta between two ventral hair insertions and near the terminal (Fig. 1E). I-L-5 longish, S-1 and S-2 both with blunt tips and with a narrow setal interspace between them; I-L-6 curved (Fig. 3A). Female (n = 1) Similar to male (Fig. 2). Setae of D1 and D2 shorter than that in male (Fig. 2A); ventral projection of P-2 not obvious, and P-3 ventral margin nearly straight (Fig. 1F). Measurements Male (n = 4) Idiosoma L 641 (585–645), W 546 (443–546); coxal field L 316 (314–325), Cx-III W 333 (333–347), ACG IL 237 (234–239), mL 125 (107–125), W 268 (268–284); infracapitular bay L 123 (118–127); genital field L 120 (119–120), Ac1–3 L 34 (33–38), 34 (34–42), 37(37–40); chelicera L 205 (204–207); infracapitulum L 159 (140–177); palp dL: P-1 29 (29–32), P-2 74 (68–74), P-3 62(59–66), P-4 95(95– 99), P-5 27 (27–29); legs segments: I-L-1 dL 48 (46–52), I-L-2 dL 93 (89–93), I-L-3 dL 80 (78–80), I-L-4 dL 119 (119–125), I-L-5 dL 163 (163–176), HB 53 (53–60), I-L-6 dL 119 (119–122), HB 22 (21–22), S-1 L 90 (78–90), S-2 L 74 (74–75); dL: II-L-1 47 (47–50), II-L-2 82 (74–82), II-L-3 71 (70–74), II-L-4 92 (92–102), II-L-5 116 (116–120), II-L-6 124 (124–127); dL: III-L-1 56 (53–57), III-L-2 90 (81–90), III-L-3 75 (73–77), III-L-4 124 (124–125), III-L-5 146 (146–154), III-L-6 141 (133–147); dL: IV-L-1 117 (117–120), IV-L-2 105 (102–113), IV-L-3 138 (135–138), IV-L-4 174 (174–180), IV-L-5 199 (199–208), IV-L-6 163 (162–170). Fig. 2. Atractides (Atractides) biprojectus Zhang, Li & Guo sp. nov. A–B. Paratype, ♀ (GUGC, Slide No. QH-HY-2020071705). A. Idiosoma, dorsal view. B. Idiosoma, ventral view. Scale bar = 100 μm. European Journal of Taxonomy 833: 121–142 (2022) 126 Female (n = 1) Idiosoma L 902, W 721; coxal field L 390, Cx-III W 477, ACG IL 272, mL 137, W 355; infracapitular bay L 165; gonopore L 146, Ap L 140, Ac1–3 L 43, 47, 47; chelicera L 267; infracapitulum L 222; palp dL: P-1 38, P-2 84, P-3 84, P-4 123, P-5 34; legs segments: I-L-1 dL 64, I-L-2 dL 113, I-L-3 dL 114, I-L-4 dL 176, I-L-5 dL 242, HB 77, I-L-6 dL171, HB 26, S-1 L 120, S-2 L 106; dL: II-L-1 72, II-L-2 Fig. 3. Atractides (Atractides) biprojectus Zhang, Li & Guo sp. nov., holotype, ♂ (GUGC, Slide No. QH-HY-2020071701). A–D. I-L–IV-L. Scale bar = 100 μm. ZHANG Y.-H. et al., New species of Atractides from China 127 98, II-L-3 96, II-L-4 135, II-L-5 153, II-L-6 162; dL: III-L-1 69, III-L-2 100, III-L-3 107, III-L-4 168, III-L-5 193, III-L-6 181; dL: IV-L-1 153, IV-L-2 141, IV-L-3 184, IV-L-4 231, IV-L-5 267, IV-L-6 211. Remarks The new species Atractides (Atractides) biprojectus sp. nov. is similar to Atractides yazdensis Pešić, Smit & Saboori, 2021 in the following points: (1) male P-2 and P-3 with ventral projections; (2) setae S-1 and S-2 separated, with a narrow setal interspace; (3) V1 separated from V2. However, A. (A.) biprojectus differs from A. yazdensis in following aspects: (1) P-4 sword seta between two ventral hair insertions in A. (A.) biprojectus, but slightly proximal to posteroventral hair in A. yazdensis; (2) apodemes from ACG not reaching to Cx-IV in A. (A.) biprojectus, but reaching to Cx-IV in A. yazdensis; (3) genital field of A. (A.) biprojectus much rounder than that of in A. yazdensis (Pešić et al. 2021). Atractides (Atractides) smiti Zhang, Li & Guo sp. nov. urn:lsid:zoobank.org:act:D2DA763A-88E0-4432-810F-76BC5FBF1F3B Figs 4–5 Diagnosis Muscle attachments between D3 sclerotized. I-L-5 longish, S-1 and S-2 both with blunt tips and with a narrow setal interspace between them; I-L-6 curved. Ac in an obtuse triangle; V1 fused to V2, excretory pore surrounded by sclerotized ring. P-2 and P-3 ventral margin slightly straight; P-4 divided by two ventral hairs in sectors 3:3:2, sword seta at the middle of P-4. Etymology The species is named after Dr Harry Smit in appreciation of his contributions to the taxonomy of water mites. Type material Holotype CHINA • ♂; Qinghai Province, Huangnan Tibetan Autonomous Prefecture, Zeku County, Maixiu Town; 35°18′64′′ N, 101°52′32′′ E; 3201 m a.s.l.; 17 Jul. 2020; Hai-Tao Li leg.; running water; GUGC, Slide No. QH-HY-2020071706. Description Male Idiosoma oval; O2 and L1 at the same level; setae of D1 about two thirds of the distance from D1 to D2; setae of D2 reaching to the level of D3; muscle attachments between D3 sclerotized; all setae surrounded by sclerites; So1 in front of A2, So2 at the same level as D1, So3 near D2, So4 at the same level as D3, So5 behind D4 (Fig. 4A). ACG fused together and with a suture, apodemes of ACG reaching to Cx-III; genital field with a development sclerotization, the anterior part of Ap with a projection, Ac in an obtuse triangle, Ac2 near Ac3 rather than Ac1, Ac3 the biggest; V1 fused to V2, V3 and V4 forming a trapezoid, V4 at the same level as the anterior of acetabular plate; excretory pore surrounded by sclerotized ring (Fig. 4B). Palp five-segmented; P-2 and P-3 ventral margins slightly straight; P-4 with numerous dorsal hairs, and divided by two ventral hairs in sectors 3:3:2, sword seta at the middle of P-4 (Fig. 4E). I-L-5 longish, S-1 and S-2 both with blunt tips and with a narrow setal interspace between them; I-L-6 curved (Fig. 5A). Measurements Male (n = 1) Idiosoma L 513, W 369; coxal field L 264, Cx-III W 164, ACG IL 175, mL 103, W 216; infracapitular bay L 97; genital field L 131, Ac1–3 L 26, 28, 27; chelicera L 145; infracapitulum L 125; palp dL: P-1 23, P-2 49, P-3 49, P-4 70, P-5 26; legs segments: I-L-1 dL 38, I-L-2 dL 74, I-L-3 dL 67, I-L-4 dL 107, http://zoobank.org/urn:lsid:zoobank.org:act:D2DA763A-88E0-4432-810F-76BC5FBF1F3B European Journal of Taxonomy 833: 121–142 (2022) 128 Fig. 4. Atractides (Atractides) smiti Zhang, Li & Guo sp. nov., holotype, ♂ (GUGC, Slide No. QH- HY-2020071706). A. Idiosoma, dorsal view. B. Idiosoma, ventral view. C. Gnathosoma. D. Chelicera. E. Palp. F. Ejaculatory complex. Scale bars = 100 μm. ZHANG Y.-H. et al., New species of Atractides from China 129 I-L-5 dL 122, HB 37, I-L-6 dL 72, HB 19, S-1 L 54, S-2 L 60; dL: II-L-1 32, II-L-2 61, II-L-3 57, II-L-4 82, II-L-5 85, II-L-6 91; dL: III-L-1 36, III-L-2 64, III-L-3 61, III-L-4 95, III-L-5 106, III-L-6 103; dL: IV-L-1 70, IV-L-2 83, IV-L-3 107, IV-L-4 138, IV-L-5 148, IV-L-6 129. Female Unknown. Remarks The new species Atractides (Atractides) smiti sp. nov. is similar to Atractides protendens K.O. Viets, 1955 in the following points: (1) P-2 and P-3 ventral margins slightly straight; (2) S-1 and S-2 with a narrow setal interspace between them; (3) the anterior part of Ap with a projection; (4) apodemes of ACG reaching to Cx-III. However, A. (A.) smiti differs from A. protendens in the following aspects: (1) V1 fused to V2 in A. (A.) smiti, but not fused in A. protendens; (2) excretory pore surrounded by sclerotized ring in A. (A.) smiti, but smooth in A. protendens; (3) the I-L-6 of A. (A.) smiti more curved than that of A. protendens (Gerecke 2003). Fig. 5. Atractides (Atractides) smiti Zhang, Li & Guo sp. nov., holotype, ♂ (GUGC, Slide No. QH- HY-2020071706). A–D. I-L–IV-L. Scale bar = 100 μm. European Journal of Taxonomy 833: 121–142 (2022) 130 Fig. 6. Atractides (Atractides) menyuanensis Zhang, Li & Guo sp. nov. A–E. Holotype, ♂ (GUGC, Slide No. QH-HY-2020072901). F. Paratype, ♀ (GUGC, Slide No. QH-HY-2020072902). A. Idiosoma, dorsal view. B. Idiosoma, ventral view. C. Gnathosoma. D. Chelicera. E. Palp. F. Palp. Scale bars = 100 μm. ZHANG Y.-H. et al., New species of Atractides from China 131 Atractides (Atractides) menyuanensis Zhang, Li & Guo sp. nov. urn:lsid:zoobank.org:act:C836E7CF-0A50-4334-AA1D-DDE500DDBCF8 Figs 6–8 Diagnosis Dorsal muscle attachment unsclerotized. I-L-5 longish, S-1 close to S-2. I-L-6 curved. Ac in an obtuse triangle; V1 separated from V2. P-2 ventral margin slightly convex; P-3 ventral margin nearly straight; two long hairs on the ventral surface of P-4 near the base, sword seta near the base. Ac in a weakly curved line in female. Etymology The new species is named after the name of Menyuan Hui Autonomous County where the specimens were collected. Type material Holotype CHINA • ♂; Qinghai Province, Haibei Tibetan Autonomous Prefecture, Menyuan Hui Autonomous County; 37°31′31′′ N, 101°21′09′′ E; 2427 m a.s.l.; 29 Jul. 2020; Hai-Tao Li leg.; running water; GUGC, Slide No. QH-HY-2020072901. Paratypes CHINA • 5 ♀♀; same collection data as for holotype; GUGC, Slides No. QH-HY-2020072902 to 2020072906. Fig. 7. Atractides (Atractides) menyuanensis Zhang, Li & Guo sp. nov., paratype, ♀ (GUGC, Slide No. QH-HY-2020072902). A. Idiosoma, dorsal view. B. Idiosoma, ventral view. Scale bars = 100 μm. http://zoobank.org/urn:lsid:zoobank.org:act:C836E7CF-0A50-4334-AA1D-DDE500DDBCF8 European Journal of Taxonomy 833: 121–142 (2022) 132 Description Male (n = 1) Idiosoma oval, dorsal muscle attachment unsclerotized; all slit organs visible, So1 near the eye capsule, So2 near L2, So3 at the level of D2, So4 at the level of D3, So5 on the outside of D4 (Fig. 6A). ACG fused together and with a suture, PCG separated; apodemes from ACG not reaching to PCG; Ac in an obtuse Fig. 8. Atractides (Atractides) menyuanensis Zhang, Li & Guo sp. nov., holotype, ♂ (GUGC, Slide No. QH-HY-2020072901). A–D. I-L–IV-L. Scale bar = 100 μm. ZHANG Y.-H. et al., New species of Atractides from China 133 triangle; V1 separated from V2; V3 and V4 forming a trapezoid, V4 at the same level as the anterior of acetabular plate (Fig. 6B). Palp five-segmented; P-2 ventral margin slightly convex; P-3 ventral margin nearly straight; P-4 with numerous dorsal hairs, two long hairs on the ventral surface of P-4 near the base, sword seta near the base (Fig. 6E). I-L-5 longish, S-1 close to S-2; I-L-6 curved (Fig. 8A). Female (n = 5) Similar to male (Figs 6F, 7). Idiosoma oval; ACG and PCG significantly smaller than the male; Ac in a weakly curved line (Fig. 7B). Measurements Male (n = 1) Idiosoma L 708, W 582; coxal field L 352, Cx-III W 415, ACG IL 232, mL 92, W 323; infracapitular bay L 146; genital field L 141, Ac1–3 L 35, 35, 38; chelicera L 223; infracapitulum L 210; palp dL: P-1 37, P-2 70, P-3 63, P-4 122, P-5 31; legs segments: I-L-1 dL 57, I-L-2 dL 106, I-L-3 dL 101, I-L-4 dL 139, I-L-5 dL 182, HB 50, I-L-6 dL 102, HB 32, S-1 L 58, S-2 L 58; dL: II-L-1 57, II-L-2 95, II-L-3 93, II-L-4 135, II-L-5 158, II-L-6 157; dL: III-L-1 55, III-L-2 102, III-L-3 114, III-L-4 165, III-L-5 191, III-L-6 180; dL: IV-L-1 118, IV-L-2 138, IV-L-3 181, IV-L-4 240, IV-L-5 272, IV-L-6 217. Female (n = 5) Idiosoma L 1074 (1050–1113), W 935 (868–935); coxal field L 385 (385–432), Cx-III W 575 (550– 585), ACG IL 248 (248–299), mL 111 (111–130), W 373 (373–417); infracapitular bay L 130 (105– 163); gonopore L 168 (161–190), Ap L 157 (145–171), Ac1–3 L 38 (34–48), 39 (39–49), 37 (32–48); chelicera L 264 (253–283); infracapitulum L 215 (214–244); palp dL: P-1 46 (40–46), P-2 75 (75–86), P-3 66 (66–80), P-4 126 (121–145), P-5 37 (36–37); legs segments: I-L-1 dL 62 (62–77), I-L-2 dL 106 (106–136), I-L-3 dL 107 (107–126), I-L-4 dL 153 (151–176), I-L-5 dL 200 (200–233), HB 53 (53–59), I-L-6 dL 120 (120–132), HB 31 (31–36), S-1 L 63 (62–68), S-2 L 63 (62–69); dL: II-L-1 61 (61–72), II-L-2 93 (93–109), II-L-3 109 (98–124), II-L-4 144 (142–163), II-L-5 168 (168–204), II-L-6 170 (170– 191); dL: III-L-1 67 (65–84), III-L-2 102 (102–116), III-L-3 119 (115–137), III-L-4 178 (178–203), III-L-5 208 (206–233), III-L-6 200 (190–212); dL: IV-L-1 149 (129–149), IV-L-2 159 (156–179), IV-L-3 202 (191–234), IV-L-4 261 (252–294), IV-L-5 286 (276–321), IV-L-6 232 (223–255). Remarks The new species Atractides (Atractides) menyuanensis sp. nov. is similar to Atractides algeriensis Lundblad, 1942 in the following points: (1) apodemes from ACG not reaching to Cx-IV; (2) P-2 ventral margin slightly convex, P-3 ventral margin nearly straight; (3) Ac in a weakly curved line in female. However, A. (A.) menyuanensis differs from A. algeriensis in following aspects: (1) two long hairs on the ventral surface of P-4 near the base, sword seta near the base in A. (A.) menyuanensis, but the ventral surface of P-4 divided by two long ventral hairs in 1:1:1, sword seta at the middle of P-4 in A. algeriensis; (2) S-1 much more close to S-2 in A. (A.) menyuanensis than in A. algeriensis; (3) I-L-6 of A. algeriensis much longer and more slender than that of A. (A.) menyuanensis (Gerecke 2003). Atractides (Atractides) longiprojectus Zhang, Li & Guo sp. nov. urn:lsid:zoobank.org:act:A043146A-40FB-45E2-888A-3613E5A14165 Figs 9–10 Diagnosis Dorsal muscle attachment unsclerotized, setae of D1 and D2 significantly longer than others, setae of D1 nearly reaching to D2, setae of D2 extending beyond D3. I-L-5 longish, S-1 and S-2 with a narrow setal interspace between them, S-1 longer than S-2. I-L-6 straight. Ac in a weakly curved line; V1 separated http://zoobank.org/urn:lsid:zoobank.org:act:A043146A-40FB-45E2-888A-3613E5A14165 European Journal of Taxonomy 833: 121–142 (2022) 134 from V2. P-2 with an unobvious ventral projection; P-3 ventral margin slightly convex; the ventral edge of P-4 divided by two long hairs in 2:1:2, sword seta at two thirds of P-4. Etymology The Latin prefix ‘longi-’ means long, ACG of the female of this new species is with a particularly long hind projection. Type material Holotype CHINA • ♀; Qinghai Province, Haibei Tibetan Autonomous Prefecture, Menyuan Hui Autonomous County, Quankou Town; 37°31′31′′ N, 101°81′12′′ E; 2691 m a.s.l.; 29 Jul. 2020; Hai-Tao Li leg.; running water; GUGC, Slide No. QH-HY-2020072907. Paratypes CHINA • 2 ♀♀; same collection data as for holotype; GUGC, Slides No. QH-HY-2020072908, 2020072909. Description Female (n = 3) Idiosoma oval, dorsal muscle attachment unsclerotized; O2 and D1 at the same level; setae of D1 and D2 significantly longer than others, setae of D1 nearly reaching to D2, setae of D2 extending beyond D3; all slit organs visible, So1 near the eye capsule, So2 at the same level as D1, So3 near D2, So4 in front of L4, So5 behind of D4 (Fig. 9A). Coxal group occupying a half of ventral surface, projections from ACG extending to Cx-IV; Ac in a weakly curved line; V1 separated from V2; V3 and V4 forming a rectangle, V4 at the same level as the anterior of acetabular plate (Fig. 9B). Palp five-segmented; P-2 with an unobvious ventral projection; P-3 ventral margin slightly convex; P-4 with numerous dorsal hairs, the ventral edge of P-4 divided by two long hairs in 2:1:2, sword seta at two thirds of P-4 (Fig. 9E). I-L-5 longish, S-1 and S-2 with a narrow setal interspace, S-1 longer than S-2. I-L-6 straight (Fig. 10A). Measurements Female (n = 3) Idiosoma L 530 (530–663), W 419 (419–547); coxal field L 320 (320–361), Cx-III W 353 (353–406), ACG IL 244 (244–295), mL 126 (126–163), W 297 (296–336); infracapitular bay L 143 (133–151); gonopore L 98 (98–118), Ap L 120 (118–128), Ac1–3 L 35 (35–41), 39 (39–45), 30 (30–38); chelicera L 251 (251–275); infracapitulum L 227 (226–239); palp dL: P-1 35 (32–35), P-2 68 (68–79), P-3 75 (75–82), P-4 106 (106–110), P-5 27 (27–31); legs segments: I-L-1 dL 45 (45–53), I-L-2 dL 103 (100– 113), I-L-3 dL 103 (96–112), I-L-4 dL 153 (152–163), I-L-5 dL 166 (166–180), HB 37 (37–39), I-L-6 dL 134 (134–144), HB 34 (34–37), S-1 L 57 (57–72), S-2 L 47 (46–54); dL: II-L-1 53 (53–56), II-L-2 96 (89–104), II-L-3 96 (92–102), II-L-4 130 (130–141), II-L-5 140 (140–153), II-L-6 141 (140–152); dL: III-L-1 53 (51–59), III-L-2 87 (79–106), III-L-3 101 (101–115), III-L-4 154 (153–168), III-L-5 178 (170–189), III-L-6 163 (160–178); dL: IV-L-1 108 (108–120), IV-L-2 141 (135–141), IV-L-3 182 (178–195), IV-L-4 219 (219–239), IV-L-5 246 (234–255), IV-L-6 204 (197–218). Male Unknown. Remarks The new species Atractides (Atractides) longiprojectus sp. nov. is similar to Atractides inflatipalpis K. Viets, 1950 in the following points: (1) V1 separated from V2; (2) S-1 longer than S-2; (3) P-2 ZHANG Y.-H. et al., New species of Atractides from China 135 with an unobvious ventral projection. However, A. (A.) longiprojectus differs from A. inflatipalpis in the following aspects: (1) P-3 ventral margin slightly convex in A. (A.) longiprojectus, but straight in A. inflatipalpis; (2) I-L-6 straight in A. (A.) longiprojectus, but curved in A. inflatipalpis; (3) the pregenital sclerite of A. inflatipalpis in female much bigger than A. (A.) longiprojectus (Gerecke 2003). Fig. 9. Atractides (Atractides) longiprojectus Zhang, Li & Guo sp. nov., holotype, ♀ (GUGC, Slide No. QH-HY-2020072907). A. Idiosoma, dorsal view. B. Idiosoma, ventral view. C. Gnathosoma. D. Chelicera. E. Palp. Scale bars = 100 μm. European Journal of Taxonomy 833: 121–142 (2022) 136 Fig. 10. Atractides (Atractides) longiprojectus Zhang, Li & Guo sp. nov., holotype, ♀ (GUGC, Slide No. QH-HY-2020072907). A–D. I-L–IV-L. Scale bar = 100 μm. ZHANG Y.-H. et al., New species of Atractides from China 137 Atractides (Atractides) xianmiensis Zhang, Li & Guo sp. nov. urn:lsid:zoobank.org:act:FB29B7EB-1A14-450E-80E2-4795C3B299EA Figs 11–13 Diagnosis Male Dorsal muscle attachment unsclerotized. I-L-5 longish, S-1 and S-2 both with blunt tips and with a setal interspace between them; I-L-6 straight. Ac in an obtuse triangle; V1 separated from V2. P-2 and P-3 with a ventral projection respectively, P-4 with numerous dorsal hairs, ventral hairs long, one at the middle of the surface, and the other one at the terminal of lateral edge, sword seta at the middle of P-4. Female Ac in a weakly curved line. P-2 with a ventral projection, P-3 ventral margin slightly convex, P-4 divided by two ventral hairs in sectors 1:1:1. Etymology The new species is named after the name of the Xianmi National Nature Reserve where the specimens were collected. Type material Holotype CHINA • ♂; Qinghai Province, Xianmi National Nature Reserve; 37°10′56′′ N, 102°20′03′′ E; 2949 m a.s.l.; 29 Jul. 2020; Hai-Tao Li leg.; running water; GUGC, Slide No. QH-HY-2020072910. Paratypes CHINA • 3 ♂♂; same collection data as for holotype; GUGC, Slides No. QH-HY-2020072911 to 2020072913 • 2 ♀♀; same collection data as for holotype; GUGC, Slides No. QH-HY-2020072914, 2020072915. Description Male (n = 4) Idiosoma oval, dorsal muscle attachment unsclerotized; So1 near eye capsule; So2 at the same level as D1; So3 at the same level as D2; So4 in front of L4; So5 behind D4 (Fig. 11A). ACG fused together and with a suture, apodemes of ACG well developed, and reaching to Cx-III; Ac in an obtuse triangle, Ac3 biggest; V1 separated far from V2, V3 and V4 forming a rectangle, V4 at the same level as the anterior part of acetabular plate (Fig. 11B). Palp five-segmented; P-2 and P-3 with a ventral projection respectively, P-4 with numerous dorsal hairs, ventral hairs long, one at the middle of the surface, and the other one at the terminal of lateral edge, sword seta at the middle of P-4 (Fig. 11E). I-L-5 longish, S-1 and S-2 with blunt tips and with a setal interspace between them; I-L-6 straight (Fig. 13A). Female (n = 2) Similar to male (Fig. 12). Ac in a weakly curved line (Fig. 12B). P-2 with a ventral projection, P-3 ventral margin slightly convex, P-4 divided by two ventral hairs in sectors 1:1:1 (Fig. 11F). Measurements Male (n = 4) Idiosoma L 724 (724–896), W 605 (605–734); coxal field L 351 (351–395), Cx-III W 426 (426–483), ACG IL 251 (251–287), mL 131 (131–159), W 329 (329–372); infracapitular bay L 132 (132–160); genital field L 131 (131–144), Ac1–3 L 39 (36–41), 32 (32–43), 36 (36–46); chelicera L 227 (227–267); infracapitulum L 207 (207–239); palp dL: P-1 30 (30–37), P-2 69 (69–80), P-3 76 (76–89), P-4 107 http://zoobank.org/urn:lsid:zoobank.org:act:FB29B7EB-1A14-450E-80E2-4795C3B299EA European Journal of Taxonomy 833: 121–142 (2022) 138 Fig. 11. Atractides (Atractides) xianmiensis Zhang, Li & Guo sp. nov. A–E. Holotype, ♂ (GUGC, Slide No. QH-HY-2020072910). F. Paratype, ♀ (GUGC, Slide No. QH-HY-2020072914). A. Idiosoma, dorsal view. B. Idiosoma, ventral view. C. Gnathosoma. D. Chelicera. E. Palp. F. Palp. Scale bars = 100 μm. ZHANG Y.-H. et al., New species of Atractides from China 139 (107–121), P-5 34 (33–34); Legs segments: I-L-1 dL 47 (47–56), I-L-2 dL 107 (107–126), I-L-3 dL 110 (110–125), I-L-4 dL 165 (165–191), I-L-5 dL 188 (188–214), HB 42 (42–46), I-L-6 dL 145 (145–160), HB 34 (32–34), S-1 L 67 (67–73), S-2 L 58 (58–65); dL: II-L-1 55 (47–59), II-L-2 94 (94–108), II-L-3 100 (100–113), II-L-4 141 (141–162), II-L-5 161 (161–184), II-L-6 154 (154–174); dL: III-L-1 54 (51– 63), III-L-2 93 (93–112), III-L-3 109 (109–124), III-L-4 166 (166–191), III-L-5 194 (194–226), III-L-6 178 (178–200); dL: IV-L-1 131 (129–137), IV-L-2 154 (154–161), IV-L-3 187 (187–211), IV-L-4 240 (240–274), IV-L-5 260 (260–303), IV-L-6 224 (224–246). Female (n = 2) Idiosoma L 925 (1215), W 754 (1042); coxal field L 403 (422), Cx-III W 515 (576), ACG IL 303 (323), mL 133 (131), W 405 (403); infracapitular bay L 180 (179); gonopore L 145 (190), Ap L 156 (156), Ac1–3 L 49 (48), 43 (45), 43 (46); chelicera L 291 (297); infracapitulum L 269 (268); palp dL: P-1 36 (46), P-2 84 (88), P-3 97 (103), P-4 124 (123), P-5 36 (39); legs segments: I-L-1 dL 59 (64), I-L-2 dL 122 (136), I-L-3 dL 131 (141), I-L-4 dL 193 (205), I-L-5 dL 220 (227), HB 47 (47), I-L-6 dL 165 (173), HB 39 (35), S-1 L 87 (78), S-2 L 74 (72); dL: II-L-1 64 (50), II-L-2 108 (106), II-L-3 121 (133), II-L-4 166 (180), II-L-5 188 (200), II-L-6 175 (186); dL: III-L-1 54 (68), III-L-2 114 (112), III-L-3 131 (142), III-L-4 198 (212), III-L-5 233 (241), III-L-6 208 (215); dL: IV-L-1 150 (160), IV-L-2 162 (174), IV-L-3 211 (228), IV-L-4 270 (293), IV-L-5 246 (314), IV-L-6 211 (265). Remarks The new species Atractides (Atractides) xianmiensis sp. nov. is similar to Atractides inflatus Walter, 1925 in the following points: (1) P-2 and P-3 of the male both with a ventral projection respectively; (2) V1 not fused to V2; (3) S-1 and S-2 both with blunt tips and with a setal interspace between them; (4) Ac in an obtuse triangle in the male and in a weakly curved line in the female. However, A. (A.) xianmiensis Fig. 12. Atractides (Atractides) xianmiensis Zhang, Li & Guo sp. nov., paratype, ♀ (GUGC, Slide No. QH-HY-2020072914). A. Idiosoma, dorsal view. B. Idiosoma, ventral view. Scale bar = 100 μm. European Journal of Taxonomy 833: 121–142 (2022) 140 Fig. 13. Atractides (Atractides) xianmiensis Zhang, Li & Guo sp. nov., holotype, ♂ (GUGC, Slide No. QH-HY-2020072910). A–D. I-L–IV-L. Scale bar = 100 μm. ZHANG Y.-H. et al., New species of Atractides from China 141 differs from A. inflatus in the following aspects: (1) apodemes of ACG in female well developed and reaching to Cx-III in A. (A.) xianmiensis, but not reaching to Cx-III in A. inflatus; (2) I-L-6 straight in A. (A.) xianmiensis, but curved in A. inflatus (Gerecke 2003). Discussion Due to the soft body wall and few specialized structures, there are only a few taxonomic features that can be used for species identification in Atractides, which might cause confusion in the taxonomy of these species. So it is of great importance to search for new taxonomic features in Atractides. Jin (1997) mentioned that the relative position of glandularia is different in various groups of water mites, and Ramírez-Sánchez et al. (2016) also mentioned that glandularia in Arrenuridae Thor, 1900 could be potential taxonomic characters. So the relative position of glandularia may be among the new taxonomic features that can be used in the taxonomy of Atractides. For example, the coxae group and palps of Atractides (Atractides) biprojectus sp. nov. and Atractides (Atractides) xianmiensis sp. nov. are similar in morphology, but the relative position of V3 in relation to V4 and V4 in relation to the genital field in A. (A.) biprojectus is significantly different from that in A. (A.) xianmiensis. Therefore, it is suggested to mention the relative position of glandularia on the body wall when describing and drawing species of Atractides. Acknowledgements Special thanks are due to professor Zhen-Ning Chen (Qinghai Normal University, P.R. China) for providing the opportunity for water mite investigation in Qinghai region. This research was supported by Guizhou Provincial Science and Technology Projects (Qiankehe Pingtai Rencai-GCC [2022]029-1) and Commissioned Project of the Qilian Mountain National Park Administration of Qinghai Province, P.R. China (QHTX-2021-006). References Cook D.R. 1974. Water mite genera and subgenera. Memoirs of the American Entomological Institute 21: 1–860. Gerecke R. 2003. Water mites of the genus Atractides Koch, 1837 (Acari: Parasitengona: Hygrobatidae) in the western Palaearctic region: a revision. Zoological Journal of the Linnean Society 138 (2–3): 141–378. https://doi.org/10.1046/j.1096-3642.06-0.00051.x Gülle P., Gülle I. & Boyaci Y. Ö. 2015. A new Atractides Koch (Acari: Hydrachnidia, Hygrobatidae) species from southwestern Turkey. Zootaxa 3957 (2): 246–248. https://doi.org/10.11646/zootaxa.3957.2.11 Gülle P., Erman O. & Boyaci Y.Ö. 2021. 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International Journal of Acarology 36 (5): 419–429. https://doi.org/10.1080/01647954.2010.483236 Manuscript received: 23 February 2022 Manuscript accepted: 1 June 2022 Published on: 3 August 2022 Topic editor: Tony Robillard Section editors: Rudy Jocqué Desk editor: Pepe Fernández Printed versions of all papers are also deposited in the libraries of the institutes that are members of the EJT consortium: Muséum national d’histoire naturelle, Paris, France; Meise Botanic Garden, Belgium; Royal Museum for Central Africa, Tervuren, Belgium; Royal Belgian Institute of Natural Sciences, Brussels, Belgium; Natural History Museum of Denmark, Copenhagen, Denmark; Naturalis Biodiversity Center, Leiden, the Netherlands; Museo Nacional de Ciencias Naturales-CSIC, Madrid, Spain; Real Jardín Botánico de Madrid CSIC, Spain; Leibniz Institute for the Analysis of Biodiversity Change, Bonn – Hamburg, Germany; National Museum, Prague, Czech Republic. https://dx.doi.org/10.24349/acarologia/20214434 https://doi.org/10.11158/saa.23.1.14 https://doi.org/10.37828/em.2021.44.1 http://dx.doi.org/10.1111/zoj.12384 https://doi.org/10.1111/jse.12092 https://doi.org/10.11865/zs.20150104 https://doi.org/10.1080/01647954.2010.483236