Rhyncaphytoptus sigouensis, Xie & Chen, 2022

Xie, Manchao & Chen, Zhenning, 2022, Two new species of eriophyoid mites (Acari: Eriophyoidea) from Qilian Mountain National Park, China, Zoological Systematics 47 (4), pp. 336-340 : 337-340

Rhyncaphytoptus sigouensis sp. nov. ( Figs 5–8 )

Diagnosis. The new species is distinct by the scapular tubercles thin and elongated. Besides that, it is characteristic as following: body fusiform, yellowish in color; gnathosoma large and projecting straight down; prodorsal shield with median line, admedian lines and submedian lines present, scapular tubercles set well ahead of rear shield margin, setae projecting forward; coxisternal plates with few lines, prosternal apodeme present; legs with tarsal empodium simple, 7-rayed; tarsal solenidion with knob; opisthosoma with 41–43 dorsal semi-annuli, smooth except caudal 9–14 dorsal annuli with microtubercles, with 91–95 ventral semi-annuli, with round microtubercles microtubercles on rear annular margins; setae h1 present; female genitalia coverflap smooth.

Description. Female (n = 6). Body fusiform, 220 (200–240), 83 (80–85) wide, 78 (72–78) thick; yellowish-brown in color. Gnathosoma 60 (58–60), projecting straight down; pedipalp coxal setae (ep) 3 (3–4), dorsal pedipalp genual setae (d) 10 (8–10). Prodorsal shield 35 (35–40), 65 (65–70) wide, covered with waxy materials, smooth except caudal 9–14 dorsal annuli with microtubercles; frontal lobe wide and somewhat rectangular. Shield with median line extending to rear shield margin and then separated by a transverse line, admedian lines and submedian lines present. Scapular tubercles set well ahead of rear shield margin, thin and elongate and cylindrical, 15 (13–15), 25 (25–30) apart; scapular setae (sc) 25 (20–25), projecting forward. Coxigenital plates with 13 (12–14) semi-annuli between coxae and genitalia. Coxal plates I and II with few lines, anterolateral setae on coxisternum I (1b) 11 (10–12), 10 (10–12) apart; proximal setae on coxisternum I (1a) 20 (20–23), 8 (8–10) apart; proximal setae on coxisternum II (2a) 35 (35–40), 26 (26–30) apart; prosternal apodeme present, 10 (9–10). Leg I 48 (46–50), trochanter 5 (no range), femur 15 (no range), basiventral femoral setae (bv) 18 (15–20); genu 6 (5–6), antaxial genual setae (l'') 30 (30–35); tibia 15 (15–17), paraxial tibial setae (l')10 (8–10), located at the inner lateral side 1/2 from base; tarsus 7 (6–7), paraxial fastigial tarsal setae (ft') 20 (20–22), antaxial fastigial tarsal setae (ft'') 20 (20– 22); paraxial unguinal tarsal seta (u′) 5 (5–6); tarsal empodium (em) 8 (7–8), simple, 7-rayed; tarsal solenidion (ω) 9 (8–9), knobbed. Leg II 46 (43–46), trochanter 5 (no range), femur 15 (no range), basiventral femoral setae (bv) 15 (15–20); genu 6 (5–6), antaxial genual setae (l'') 15 (10–15); tibia 13 (12–13); tarsus 7 (6–7), paraxial fastigial tarsal setae (ft') 15 (15–20), antaxial fastigial tarsal setae (ft'') 20 (20–22); paraxial unguinal tarsal seta (u′) 5 (5–6); tarsal empodium (em) 8 (7–8), simple, 7-rayed; tarsal solenidion (ω) 9 (8–9), knobbed. Opisthosoma with 42 (41–43) dorsal semi-annuli, covered with woolly waxy materials, smooth except caudal 9–14 dorsal annuli with microtubercles; with 94 (91–95) ventral semi-annuli, with round microtubercles except caudal 5–6 ventral semi-annuli with elongated microtubercles; setae c2 20 (20–30) on ventral semi-annulus 18–19, 62 (62–65) apart; setae d 35 (35–40) on ventral semi-annulus 38–39, 43 (40–45) apart; setae e 15 (15– 18) on ventral semi-annulus 54–55, 25 (23–25) apart; setae f 30 (30–40) on 7 ventral semi-annulus from rear, 30 (30–33) apart. Setae h1 6 (5–6), 8 (7–8) apart; setae h2 90 (80–100), 12 (10–12) apart. Female genitalia 22 (20–22), 30 (28–30) wide, coverflap smooth, setae 3a 15 (15–17), 22 (20–22) apart.

Male. Unknown.

Material examined. Holotype ♀, from Salix myrtillacea Anderss ( Salicaceae ), Sigou Scenic Area, Menyuan, Qinghai, China, 37°07´52"N, 102°23´57"E, elev. 2572 m, 25 July 2020, coll. Manchao Xie. Paratypes. 5♀, same data as holotype .

Biology. The mites are vagrant on the undersurfaces of leaves, with no damage observed.

Etymology. The specific name is referring to the type locality, Sigou, with ensis, masculine ending.

Remarks. The genus Rhyncaphytoptus Keifer, 1939 includes about 115 species in the world (Amrine & Stasny, 1994; Amrine et al., 2003; Hong et al., 2010; Li et al., 2012, 2015; Rajput et al., 2015, Xie, 2018, 2019; Xue & Li, 2020), of which about 50 species are distributes in China.

Salix spp. (willow trees) are mainly distributed in temperate regions of the Northern Hemisphere. Up to now, seven eriophyoid mite species of Rhyncaphytoptus have been reported on Salix spp. , namely R. funali Xue, Song & Hong, 2009 on S. sp. from China (Shaanxi), R. tibetisalicise Song, Xue & Hong, 2009 on S. sp. from China (Tibet), R. acilius Keifer, 1939 on S. lasiolepis from USA, R. alsasuensis Roivainen, 1953 on S. aurita from Spain, R. capreae Liro, 1942 on S. caprea from Finland, R. salicifoliae Keifer, 1939 on S. sitchensis angustifolia from USA, and R. salicisglaucae Roivainen, 1950 on S. glauca from Sweden.

The new species is very similar to R. tibetisalicise Song, Xue & Hong, 2009 by the tarsal empodium shapes and female coverflap smooth, but can be easily differed from the later by the opisthosoma dorsal semi-annuli without linear microtubercles (vs. with linear microtubercles in R. tibetisalicise ), tarsal empodium 6-rayed (vs. 12-rayed in R. tibetisalicise ).

Funding This work is supported by a special project funding for insect survey from the Qinghai Provincial Administration of Qilian Mountain National Park (In 2019, the Second Batch of Forestry Reform and Development Funds subsidies for National Nature Reserves: Qilian Mountain National Park Capacity Construction Project 2019-061).

Acknowledgements We greatly thank all reviewers for their valuable comments on the manuscript.

Manchao Xie1, Zhenning Chen2 1Key Laboratory of Tea Built Jointly by the Provincial and Municipal Governments in Shaanxi Province, School of Modern Agriculture and Biotechnology, Ankang University, Ankang 725000, China

2 Key Laboratory of Medicinal Animal and Plant Resources of Qinghai-Tibetan Plateau in Qinghai Province, School of Life Science , Qinghai Normal University, Xining 810008, China

Figures

Figures 5–8. Rhyncaphytoptus sigouensis sp. nov., female. 5. Dorsal view. 6. Antero-lateral view of body region. 7. Empodium (enlarged). 8. Coxal-genital region. Scale bars=10μm.