Neodicrothrix grandcaputus, Yuan & Xue, 2019

Yuan, Yan-Mei & Xue, Xiao-Feng, 2019, Two new species of eriophyid mites (Acari: Eriophyidae) from Malaysia, Zootaxa 4613 (1), pp. 152-160 : 153-155

Neodicrothrix grandcaputus sp. nov.

( Figs 1–2 )

Description. Female (n = 7): Body fusiform, 150 (140–163), 67 (48–68) wide; white in colour. Gnathosoma 18 (17–24), projecting downwards, pedipalp coxal seta (ep) absent, dorsal pedipalp genual setae (d) divided, the longer branch 10 (9–11), the shorter branch 3 (3–4) ( Figure 1F ). Prodorsal shield broad, pentagon, 73 (66–80) including the frontal lobe, 67 (57–70) wide; with a “latin cross” shape at shield center formed by curved lines, two faint curved lines present at posterior of shield. Scapular tubercles ahead of rear shield margin, setae sc 20 (18–24), 27 (26–30) apart, projecting outwards or upwards. Coxigenital region smooth between coxae and genitalia; coxal plates smooth, anterolateral setae on coxisternum І (1b) 5 (5–6), 10 (8–10) apart; proximal setae on coxisternum І (1a) 8 (7–9), 8 (7–8) apart; proximal setae on coxisternum ІІ (2a) 16 (16–19), 14 (10–14) apart. Prosternal apodeme 6 (6–10). Leg І 22 (22–25), femur 11 (11–12), basiventral femoral setae (bv) 8 (6–8); genu 1 (1–1), antaxial genual setae (l'') 18 (15–18); tibia 4 (4–5), paraxial tibial setae (l') absent; tarsus 3 (3–4), paraxial fastigial tarsal setae ft’ 12 (12–16), abruptly bended at base, antaxial fastigial tarsal setae ft’’ 14 (14–19), abruptly bended at base; tarsal empodium (em) 4 (3–5), simple, 5-rayed, tarsal solenidion (ω) 5 (4–6), knobbed. Leg ІІ 20 (20–23), femur 10 (10–11), basiventral femoral setae (bv) 7 (4–7); genu 1 (1–1), antaxial genual setae (l'') absent; tibia 3 (3–4); tarsus 3 (3–4), paraxial fastigial tarsal setae ft’ 6 (6–8), antaxial fastigial tarsal setae ft’’ 11 (11–16), abruptly bended at base ( Figure 1E ); tarsal empodium (em) 3 (3–4), simple, 5-rayed, tarsal solenidion (ω) 4 (4–5), knobbed. Opisthosoma dorsally with 17 (17–21) annuli, smooth, ventrally with 24 (24–26) semiannuli, with elliptical to linear microtubercles. Setae c2 6 (6–7), on ventral semiannulus 1*, 40 (32–40) apart; setae d absent; setae e absent; setae f 8 (6–8), 14 (13–15) apart, on 5th ventral semiannulus from rear; setae h1 absent, setae h2 25 (21–25). Female genitalia 13 (10–14), 20 (16–21) wide, coverflap smooth, setae 3a 6 (5–7), 13 (13–15) apart. Internal genitalia: spermathecae ovoid, oriented posterolaterad; spermathecal tubes relatively short; transverse genital apodeme trapezoidal, distally folded.

Male: Unknown.

Type material. Holotype, female (slide number NJAU-KK7.1 ; marked Holotype), found on Stachyurus himalaicus (Stachyuraceae) , Mountain Trusmadi , Keningau, Sabah, Malaysia, 5°47′59″N, 116°27′05″E, elevation 1182 m, 1 May 2017, coll. Xiao-Feng Xue, deposited as a slide-mounted specimen in NJAU . Paratypes, 7 females on 7 slides (slide number NJAU-kk7.2–NJAU-kk7.7 ; marked Paratypes), from Stachyurus himalaicus (Stachyuraceae) , same details as holotype, deposited as slide-mounted specimens in NJAU .

Relation to the plant host. Vagrant on lower leaf surface. No damage to the host plant was observed.

Etymology. The new species has a broad prodorsal shield which looks like a big head. The specific designation grandcaputus is derived from the combination of grandis (Latin, big) and caput (Latin, head), adding the suffix; masculine in gender.

Differential diagnosis. To date, four Neodicrothrix species were reported world-wide; N. grandcaputus sp. nov. is the 5th species to be described in the genus. It can be distinguished from the other four Neodicrothrix species (N. piperae Mohanasundaram, 1989, N. tiliacora, N. celloshieldae and N. rutacevagrans) by having the female genital coverflap smooth (coverflap with lines or ridges in the other species), scapular setae sc 20 (18–24) (setae sc is shorter in the other species), genu very short on both legs while femur, tibia and tarsus normal (all segments normal on both legs in the remaining four Neodicrothrix species), and a distinct prodorsal shield design. Other remarkable differences between the new species and the other four species are the following characters: length and width of body, number of dorsal and ventral annuli, prodorsal shield length, distance between scapular tubercles, and length of setae sc, c2, f and 3a ( Table 1 ).

Figures

FIGURE 1. Neodicrothrix grandcaputus sp. nov. (female) A, dorsal view; B, coxigenital area; C, ventral view of telosoma; D, lateral microtubercles; E, leg II; F, divided dorsal pedipalp genual setae d; G, internal genitalia. Scale bar: 10 μm.

FIGURE 2. Neodicrothrix grandcaputus sp. nov. (female) D, dorsal view of female; d, divided dorsal pedipalp genual setae d; em, empodium; L1, leg І; L2, leg 2; PM, dorsal view of telosoma; CG, coxigenital area; LO, lateral microtubercles; IG, internal genitalia. Scale bar: 10 μm for D and CG; 5 μm for IG, PM, LO, L1, and L2; 2.5μm for em and d.