Protoribates geonjiensis ( Choi, 1994 )

Chen, Shujing Xu Yannan & Chen, Jun, 2020, New species and records of oribatid mites of the genus Protoribates (Acari Oribatida, Haplozetidae) from China, Zootaxa 4772 (3), pp. 469-511 : 490

Protoribates geonjiensis ( Choi, 1994)

( Figs 15–16 )

Xylobates geonjiensis Choi, 1994: 42–43 , fig. 3.

Protoribates (Protoribates) geonjiensis ( Choi,1994) : Subías, 2004: 206.

Supplementary description. Body length 400–420, width 190–200. Body color brown. Body surface punctate.

Prodorsum. Rostrum slightly truncate. Lamellae located dorsolaterally, longer than half of prodorsum. Rostral setae (25–28) setiform, thin, smooth. Lamellar setae minute (7), setiform, thin, smooth, inserted medially to lamellar ends. Interlamellar setae (30–32) slightly thicker and longer than rostral setae, setiform, barbed. Bothridial setae (75–87) with long stalk and short, unilaterally dilated, apically pointed, barbed head. Dorsophragmata comparatively long, longitudinally elongated, directed posteromedially.

Notogaster. Anterior notogastral margin convex medially, fine. Pteromorphs with distinct hinges. Ten pairs of notogastral setae short (10–16), thin, smooth. Three pairs of rounded porose areas, Aa larger (7–8) than A1 and A2 (4–5). Areae porosae A3 absent. Distance between porose areas A1–A1 subequal to A2–A2. All lyrifissures and opisthonotal gland openings clearly visible.

Gnathosoma . Subcapitulum longer than wide (100–121 × 65–75). Subcapitular setae (a, h) similar in length (17–19), setiform, a thicker than h; setae m (8) short, thinnest.

Epimeral and lateral podosomal regions. Epimeral setal formula: 3-1-3-2. Epimeral setae setiform, thin, smooth, 1b (18–20) longer than others (8–10) (3c and 3b we can’t measure precisely). Discidium triangular. Circumpedal carinae of medium size, directed to pedotecta II, but not reaching it.

Anogenital region. Five pairs of genital (g 1, 10–12; g 2 –g 5, 5–8), one pair of aggenital (8–11), two pairs of anal (11–15) and three pairs of adanal (11–15) setae setiform, thin, smooth. Adanal setae ad 1 in posterior, ad 2 in lateral, ad 3 in anterior positions. Adanal lyrifissures located close and parallel to anal aperture.

Legs. Monodactylous.

Material examined. Two females (on permanent slides, W-88-1): China, Hunan, Changsha, Yuelu Mountain , soils under secondary evergreen broad-leaved forest, 10.IX.1988, collected by Huifu Wang.

Distribution. China (Hunan), Korea.

Remarks. The main diagnostic characters of the species are the extremely short lamellar setae and its insertion medially to the lamellar ends. In having these characters, it is very similar to P. cattienensis Ermilov & Anichkin, 2011 . The species differs from the latter by the bothridial setae with unilaterally dilated head (vs. bothridial setae setiform or with slightly unilaterally dilated head; see figs 15 and 23).

The specimens we examined differ from the original description ( Choi, 1994) in the number of porose areas on notogaster. The original description states that there are four pairs of porose areas, whereas only three pairs of porose areas can be seen in our examined specimens. Apart from that, there are no other differences between the characters of the specimens we examined with the original description.

Figures

FIGURE 15. Protoribates geonjiensis Choi, 1994, adult. A. dorsal view; B. bothridial setae. Scale bars: A=50 μm, B=25 μm.

FIGURE 16. Protoribates geonjiensis Choi, 1994, adult. ventral view. Scale bar 50 μm.