Basiceramerus ovatus, Zheng & Chen, 2021

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

Basiceramerus ovatus sp. nov.

Figures 1 , 2 , 3 , 4 , 5

Diagnosis.

Body size (N = 4): 990-1360 × 540-650. Two pairs of prodorsal condyles present, similar in shape, broadly rounded, median prodorsal condyles close to each other but not fused. Lateral notogastral condyles triangular, with a tiny convex at bottom. One median notogastral condyle, rounded. Ten pairs of notogastral setae. Vitta marginalis distinct. A wavy marginalis, like vitta marginalis, passing the base of adanal setae, ended at level of anterior margin of anal opening.

Description.

Measurements. Body length: 1020 (holotype, male), 990-1360 (paratypes, two males and one female), body width: 540 (holotype, male), 540-650 (paratypes, two males and one female). Setae length and mutual distance (holotype, male): ro 120, le 140, bs 130, in 110, ex 20; c, la, lm, lp, h 1, h 2, h 3, p 1, p 2, p 3 range 80-100; c - c 370, la - la 430, lm - lm 470, lp - lp 470.

Integument. Body color light brownish. Surface of notogaster foveolate.

Prodorsum. Rostrum rounded. Rostral setae moderately curved inward, densely barbed outside. Lamellar setae inserted behind tip of lamella, curved inward, roughened outside. Interlamellar setae barbed and setiform, a pair of longitudinal wrinkles extending from its bottom backward to outer margin of median prodorsal condyles. Exobothridial setae short. Bothridial seta with a fusiform head. Tutorium developed, almost touching lamelliform expansion. Lamelliform expansion pointing to bottom of seta ro. Bothridium opening laterally, dorsal bothridial plate nearly straight, ventral bothridial plate broadly rounded in dorsal view. Two pairs of prodorsal condyles present, similar in shape, broadly rounded, median prodorsal condyles close to each other but not fused. Mutual distance between ventral bothridial plates nearly equal with that between lateral prodorsal condyles.

Notogaster. L/W of notogaster about 1.3. Lateral notogastral condyles triangular, with a tiny convex at bottom. One median notogastral condyle present, rounded. Ten pairs of notogastral setae, glabrous, setiform, nearly equal in length. Setae lm and lyrifissures im located nearly same level. All lyrifissures (im, ip, ih, ips, except ia) well visible in dorsal view, ip located between p 2 and p 3, ips between h 3 and p 3. Opisthonotal gland openings located anterior and very close to im. Vitta marginalis distinct.

Epimeral and lateral podosomal regions. Apodemes II and sejugal apodeme well developed, apodemes III invisible, epimeral foramen present, pedotectum II with anterior and posterior expansions nearly equal in size. Sternal apodeme well visible. Epimeral setal formula 3-1-3-3. Seta 4a inserted between 4b and 4c, and closer to 4c. Postpodosomal ornamentation well developed.

Anogenital region. Genital plates smooth. 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, seta an 1 located close to median margin of anal opening) and three pairs of adanal setae similar in length. Setae ad 3- ad 3 well below level of anterior margin of anal opening. Anal plate foveolate. Lyrifissures iad located in diagonal position and close to anal aperture, below level of anterior margin of anal opening. A wavy marginalis, like vitta marginalis, passing the base of adanal setae, ending beyond 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 tarsusand 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 1 ): I (1-4-3-4-16) [1-2-2], II (1-4-3-3-15) [1-1-2], III (2-3-1-2-15) [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.

Holotype: male (in alcohol, ZLH-12-225): China, Yunnan Province, Ruili City, Nongdao Town, Nankaiba Village , 23°54'51.19"N, 97°33'58.69"E, 835 m a. s. l., in soil and debris under bush, 23 October 2012 . Paratypes: two females (in alcohol, ZLH-12-225): same data as holotype ; one female (in alcohol, ZLH-12-259): China, Yunnan Province, Yingjiang County, Daonong Village , 24°40'2.568"N, 97°35'54.24"E, 924 m a. s. l., in soil and debris under bush, 31 October 2012. All type specimens were collected by Lihao Zheng.

Type deposition.

All type specimens are deposited in the collection of the Institute of Zoology, Chinese Academy of Sciences, Beijing (IZAS).

Etymology.

The specific name " Basiceramerus ovatus " is from Latin for “egg” refers to the oval notogaster in dorsal view.

Remarks.

The new species is morphologically similar to B. bangladeshensis Corpuz-Raros & Gruèzo, 2008 from Bangladesh and B. igorotus Corpuz-Raros & Gruèzo, 2011 from the Philippines and Vietnam ( Ermilov and Anichkin 2013) in having two median prodorsal condyles. However, the new species differs from B. bangladeshensis by the wavy marginalis, like vitta marginalis, passing the base of adanal setae (vs. none), prodorsal condyles well separated from the median ones (vs. all prodorsal condyles touching at base), ventral ridge present (vs. none), anal plate foveolate (vs. granulate, without foveolae). The species B. igorotus was reported from the Philippines and Vietnam by Corpuz-Raros and Gruèzo (2011) and Ermilov and Anichkin (2013) respectively. The latter recorded instances of intraspecific or geographical variability based on their specimens from Vietnam: body size larger and more elongate, interlamellar setae shorter, lamellar setae longer, lateral notogastral condyles narrower, medial notogastral condyles touching base of lateral notogastral condyles, genital plate smooth in the Vietnamese specimens. The new species differs from B. igorotus from Vietnam by the wavy marginalis passing the base of adanal setae (vs. none), tutorium and lamelliform expansion nearly touching (vs. well separated), ventral ridge present (vs. none), genital plate smooth (vs. finely striate), seta an 1 located close to the median margin of the anal opening (vs. an 1 well removed from median margin of anal opening); it differs from B. igorotus from the Philippines by the lamellar setae inserted behind the tip of the lamella (vs. lamellar setae arising outside the base of cuspis), separated prodorsal condyles (vs. prodorsal condyles all touching at base), im posterior to gla (vs. im anterior to gla), genital plate smooth (vs. finely striate), anal plate foveolate (vs. granulate), wavy marginalis, like vitta marginalis, passing the base of adanal setae (vs. none).

Figures

Figure 1. Basiceramerus ovatus sp. nov. adult: a dorsal view (legs not illustrated) b bothridial seta c ventral view (legs not illustrated). Abbreviations and notations explained in text. Scale bars: 200 μm (a, c); 100 μm (b).

Figure 2. Basiceramerus ovatus sp. nov., adult, microscope images: a dorsal view b ventral view c lateral view. Abbreviations and notations explained in text. Scale bars: 200 μm (a-c).

Figure 3. Basiceramerus ovatus sp. nov. adult: lateral view (legs not illustrated). Abbreviations and notations explained in text. Scale bar: 200 μm.

Figure 4. Basiceramerus ovatus sp. nov. adult: a subcapitulum, ventral view b left palp, abaxial view c left chelicera, adaxial view. Abbreviations and notations explained in text. Scale bars: 50 μm.

Figure 5. Basiceramerus ovatus sp. nov., adult: a-d leg I-IV, left, antiaxial view. Abbreviations and notations explained in text. Scale bars: 100 μm (a-d).