Plonaphacarus hamulus Niedbała, 2011

Niedbała, Wojciech & Ermilov, Sergey G., 2011, New and little known species of ptyctimous mites (Acari, Oribatida) from Ethiopia, Zootaxa 2739, pp. 60-68 : 65

Plonaphacarus hamulus Niedbała , sp. nov.

( Figs 3. A–G )

Material examined. Holotype (in DATE): Africa, Ethiopia, 6º42’N, 39º43’E, 2 249 m above sea level, Bale Mountains National Park, Harenna Forest (wood species Hagenia abissinica forming the canopy), in mosses on trees, 23.11.2009, collected by L.B. Rybalov

Measurements of holotype. Prodorsum: length 404, width 278, height 151, sensillus 48, setae: interlamellar 265, lamellar 25, rostral 111; notogaster: length 828, width 565, height 454, c 1 116, c 2 379, h 1 156, p 1 167; genitoaggenital plate 222 × 177, anoadanal plate 257 × 187.

Description. Colour brown. Cuticle well sculptured, surface of notogaster covered with weak reticulation. Prodorsum with sigillar field feebly visible but median sigillar field large. Lateral carinae present. Sensilli short, club-like with rounded head. Interlamellar setae probably hooked distally (they are broken) and similar to hooked notogastral setae, rostral setae slightly roughened, hooked and flagellate distally, lamellar setae small spiniform, exobothridial setae vestigial.

Notogaster with 15 pairs of setae. Setae c 2, c 3 and cp long, weakly rugose, hooked distally, other setae short, rigid, covered with small spines in distal half. Setae c 2 situated near anterior border of notogaster, setae c 1 and c 3 remote from border. Four pairs of lyrifissures ia, im, ip, ips present. Vestigial setae invisible.

Ventral region. Setae h of mentum long, considerably longer than distance between them. Genitoaggenital plates with nine pairs of genital setae with arrangement: 4+2:3. Anoadanal plates each with five pairs of rough setae, anal and ad3 setae similar in length, setae ad 1 longer, setae ad 2 the longest, hooked distally.

Legs. Formula of setae and solenidia of complete type. Setae d of femora I remote from distal end of segment.

Etymology. The specific name hamulus is derived from Latin for “a small hook” and alludes to the shape of notogastral setae c 2, c 3, cp and adanal setae ad 2.

Comparison. The new species is easy distinguishable from its congeners by the presence of heterotrichy of notogastral setae, setae c 2, c 3 and cp being long and hooked distally, other setae short, rigid, covered with spines in distal half.

Figures

FIGURE 3. A – G. Plonaphacarus hamulus sp. nov. (A) dorsal view of prodorsum, (B) sensillus, dorsal view, (C) lateral view of body, (D) mentum of infracapitulum, (E) genitoaggenital and anoadanal plates, (F) trochanter and femur I, (G) tibia IV.