Aculus hypoleus, Xie, 2018

Xie, Manchao, 2018, Three new species of eriophyid mites from Wanglang Nature Reserve, Sichuan, China (Acari: Eriophyidae), Zoological Systematics 43 (4), pp. 429-436 : 433

Aculus hypoleus sp. nov. ( Figs 7–13 )

Diagnosis. Body fusiform, light yellowish in color. Gnathosoma projecting obliquely down. Prodorsal shield with a rounded frontal lobe over gnathosoma base. Shield design with H-shaped mark just ahead of rear margin. Scapular tubercles on rear shield margin, scapular setae (sc) directing to rear. Coxisternal plates smooth, prosternal apodeme present. Legs with tarsal empodium simple, 6-rayed, tarsal solenidion knobbed slightly. Opisthosoma with 23–26 dorsal annuli and 58–60 ventral annuli, dorsal annuli smooth. Female genitalia coverflap with 10 longitudinal ridges, setae 3a 40–50.

Description. Female (n = 9). Body fusiform, 180 (150–200), 70 (70) wide, 65 (65–70) thick; light yellowish in color. Gnathosoma 23 (23), projecting obliquely downwards; dorsal pedipalp genual setae (d) 6 (6–7), pedipala coxal setae (ep) 3 (2–3). Prodorsal shield subelliptical, 43 (41–48), 60 (60–67) wide, with a rounded frontal lobe over gnathosoma base. Shield design with a H-shaped mark just ahead of rear margin. Scapular tubercles on rear shield margin, 30 (28–30) apart; scapular setae (sc) 13 (13–15), projecting to rear. Coxigenital region with 5 (4–6) microtuberculated semiannuli. Coxal plates smooth, anterolateral setae on coxisternum I (1b) 5 (4–5), 12 (10–12) apart; proximal setae on coxisternum I (1a) 15 (15–18), 6 (6– 8) apart; proximal setae on coxisternum II (2a) 30 (27–35), 26 (25–26) apart; prosternal apodeme 5 (5). Leg I 35 (31–36), trochanter 2 (2–3), femur 11 (10–11), basiventral femoral setae (bv) 13 (10–13); genu 5 (5), antaxial genual setae (l'') 25 (22–25); tibia 10 (8–10), paraxial tibial setae (l')5 (5–7), located 1/3 from dorsal base; tarsus 7 (6–7), both setae ft' and setae ft'' 20 (20–22); tarsal empodium (em) 6 (5–6), entire, 6-rayed; tarsal solenidion (ω) 7 (6–7), knobbed slightly. Leg II 32 (29– 33), trochanter 2 (2–3), femur 11 (10–11), basiventral femoral setae (bv) 15 (11–15); genu 5 (5), antaxial genual setae (l'') 8 (7–8); tibia 7 (6–7); tarsus 7 (6–7), setae ft' 7 (5–7), setae ft'' 20 (20–22); tarsal empodium (em) 6 (5–6), entire, 6-rayed; tarsal solenidion (ω) 7 (6–7), knobbed slightly. Opisthosoma with 24 (23–26) dorsal annuli, smooth; ventrally with 58 (56– 70) semiannuli, with round microtubercles on rear annular margins except 5–6 ventral annuli with elongated microtubercles. Setae c2 23 (17–25) on ventral annulus 8–9, 53 (48–55) apart; setae d 40 (40–45) on ventral annulus 23–24, 32 (25–32) apart; setae e 15 (13–15) on ventral annulus 39–40, 15 (13–15) apart; setae f 20 (20–23) on 5th ventral annulus from rear, 20 (18–21) apart. Setae h1 3 (3), 5 (5) apart; setae h2 60 (60–70), 8 (8) apart. Female genitalia 16 (16–18), 24 (22–26) wide, coverflap sculptured with 10 longitudinal ridges, setae 3a 40 (40–50), 13 (12–13) apart.

Male. Unknown.

Material examined. Holotype, female, from Maddenia hypoleuca Koehne (Rosaceae) , Wanglang Nature Reserve (32º54′47′′N, 104º09′17′′E; elev. 2429 m), Pingwu County, Sichuan, China, 15 August 2016, coll. Manchao Xie. Paratypes. 8 females, the same data as holotype.

Relation to host. The mites are vagrants on the undersurfaces of the leaves, no obvious damage seen.

Etymology. The specific name is from the Latin hypole and us, hypole is derived from the host plant, and us is for masculine gender end.

Remarks. The new species is the second eriophyid mites reported from Maddenia hypoleuca , besides Diptacus maddenis Song, Xue & Hong, 2007 in Heilongjiang and Shaanxi. The new species is characteristic by the H-shaped mark on shield, the 6-rayed tarsal empodium and the long setae 3a. It is similar to A. shaoxingensis Kuang, 1998 by the shield design with lines and the coxal plates smooth, but distinguished from the latter by having a round frontal lobe of prodorsal shield, the tarsal empodium 6-rayed and female coverflap with 10 longitudinal ridges, while A. shaoxingensis have four thorn addition on frontal lobe of prodorsal shield, tarsal empodium 4-rayed and female coverflap smooth.

Figures

Figures 7–13. Aculus hypoleus sp. nov., female. 7. Antero-dorsal view. 8. Coxal-genital region. 9. Caudal opisthosoma. 10. Anterolateral view. 11. Lateral opisthosoma (enlarged). 12. Empodium (enlarged). 13. Postero-lateral view. Scale bars: 7–10, 13=20μm.