Eurostocepheus (Eurostocepheus) mahunkai Mondal & Kundu, 1999

Zheng, Lihao & Chen, Jun, 2021, Two new species and new records of Otocepheidae (Acari, Oribatida) from Yunnan, Southwest China, ZooKeys 1073, pp. 177-199 : 177

Eurostocepheus (Eurostocepheus) mahunkai Mondal & Kundu, 1999

New record for China Figures 11 , 12 , 13 , 14

Eurostocepheus (Eurostocepheus) mahunkai Mondal & Kundu, 1999: 180-186, figs 1-16.

Diagnosis.

Body size: 830 × 420. Body ratio (length/width): 2.0. Mutual distance of costula gradually narrow from base to tip. Two pairs of prodorsal condyles present, lateral prodorsal condyles broadly rounded, with bottom straight, median prodorsal condyles rounded, not conspicuous, well separated from each other. Lateral notogastral condyles trapezoid, with triangular tip outside. Epimeral setal formula 3-1-3-3. Genital plates with longitudinal furrows.

Description.

Measurements (holotype, male). Body length: 830, body width: 420. Setae length and mutual distance: ro 120, le 130, bs 100, in 160, ex 10; notogastral setae range 150-190; c - c 170, la - la 220, lm - lm 180, lp - lp 230, h 2- h 2 240, h 1- h 1 130.

Integument. Body color light brownish. Body surface densely foveolate (not well visible on notogaster).

Prodorsum. Rostrum broadly rounded. Rostral setae moderately curved inward, densely barbed outside. Lamellar setae inserted behind tip of costula, curved inward, roughened externally. Interlamellar setae slightly barbed. Bothridial setae with a long fusiform head and a strongly curved peduncle. Exobothridial setae short. Mutual distance of costula gradually narrow from base to tip. Bothridium opening laterally, dorsal bothridial plate nearly straight, ventral bothridial plate triangular in dorsal view. Tutorium fainted. Two pairs of prodorsal condyles present, lateral prodorsal condyles broadly rounded, with bottom straight, median prodorsal condyles rounded, not conspicuous, well separated from each other. Mutual distance between ventral bothridial plate nearly equal with that between lateral prodorsal condyles. Subpedotectum well developed. Notogaster. L/W of notogaster about 1.2. Surface of notogaster relatively smooth in dorsal view. Anterior margin of notogaster slightly curved forward. Lateral notogastral condyles trapezoid, with triangular tip outside. Median notogastral condyles absent. Ten pairs of notogastral setae slightly barbed, setiform. A pair of notchs present in external margin of anterior notogaster, beside lyrifissure ia. All lyrifissures well visible, ip located between p 2 and p 3, ips between h 3 and p 3. Opisthonotal gland openings located posterior and close to lyrifissure im. Vitta marginalis distinct. Lyrifissures im and setae lm located nearly same line.

Epimeral and lateral podosomal regions. Epimere I with distinct, long, transverse ridge. Apodemes I, II and sejugal apodeme well developed, apodeme III short. Sternal apodeme well developed. Epimeral setal formula 3-1-3-3. Seta 4a inserted between 4b and 4c, and closer to 4c. Postpodosomal ornamentation present.

Anogenital region. Genital plates covered with longitudinal furrows. Four pairs of genital setae (mutual distances g 1- g 1≈ g 2- g 2≈ g 4- g 4<g 3- g 3). Aggenital lyrifissures located close and anterolateral to genital aperture. One pair of aggenital, two pairs of anal (mutual distances an 1- an 1≈ an 2- an 2) and three pairs of adanal setae similar in length. Setae ad 3- ad 3 below level of anterior margin of anal opening. Adanal lyrifissures located in diagonal position and close to anal aperture, below level of anterior margin of anal opening.

Gnathosoma. Subcapitular setae barbed, flagelliform at tips. Rutellum pantelobasic, with typical dentation and rutellar brush. Chelicera chelate-dentate; with a minute denticle proximal to seta cha; cha longer than chb, both of them barbed; Trägårdh’s organ narrowly triangular. Palp with usual setal formula: 0-2-1-3-8 (+ ω); setae of trochanter to tibia barbed. Tarsus with four short, blunt distal eupathidia- acm, su, (ul); other tarsal setae smooth or with sparse, inconspicuous barbs; base of solenidion ω constrainted by surface of tarsus, and thus adjacent to setae ul ', ul " medioanteriorly. Postpalpal setae erect, smooth.

Legs. Monodactylous. Claw of each leg strong and smooth. Formulae of leg setation and solenidia (Table 3 ): I (1-4-3-4-16) [1-2-2], II (1-4-3-3-15) [1-1-2], III (1-2-1-2-15) [1-1-0], IV (1-2-2-2-12) [0-1-0]. Leg setae u setiform (L-type) on tarsi I, thorn-like (S-type) on tarsi II-IV.

Material examined.

One male (in alcohol, ZLH-12-229): China, Yunnan Province, Ruili City, Nongdao Town , 23°59'49.1"N, 97°39'10.79"E, 1150 m a. s. l., primary forest, litter and soil under bamboo, 24 October 2012, collected by Lihao Zheng.

Specimen deposition.

Specimen is deposited in the collection of the IZAS.

Remarks.

The specimen collected from Yunnan, Southwest China is morphologically coincident (shape of costula, unsmooth genital plates, epimeral setal formula, etc) with E. (E.) mahunkai described and illustrated by Mondal and Kundu (1999) from Darjeeling, Bengal, India, except for the shape of lateral notogastral condyles (trapezoid in our specimen vs. triangular in Mondal and Kundu’s description). Considering that there is intraspecific variation in the shape of notogastral or prodorsal condyles in Otocepheidae ( Aoki 1967; Zheng and Chen 2020), we identified this specimen as E. (E.) mahunkai , which has not been recorded in China before.

Figures

Figure 11. Eurostocepheus (Eurostocepheus) mahunkai Mondal & Kundu, 1999, adult: a bothridial seta b dorsal aspect (legs removed) c ventral aspect (legs and mouthparts removed) d lateral notogastral condyle (right). Abbreviations and notations explained in text. Scale bars: 200 µm.

Figure 12. Eurostocepheus (Eurostocepheus) mahunkai Mondal & Kundu, 1999, adult, microscope images: a dorsal view, ventral view c lateral view. Abbreviations and notations explained in text. Scale bars: 100 µm.

Figure 13. Eurostocepheus (Eurostocepheus) mahunkai Mondal & Kundu, 1999, adult: a subcapitulum, ventral view b left palp, abaxial view c left chelicera, adaxial view. Scale bars: 50 μm.

Figure 14. Eurostocepheus (Eurostocepheus) mahunkai Mondal & Kundu, 1999, adult: a subcapitulum, ventral view b left palp, abaxial view c left chelicera, adaxial view. Scale bars: 50 μm.