Tamdamaeus staryi, Miko & Ermilov, 2017

Miko, Ladislav & Ermilov, Sergey G., 2017, Tamdamaeus staryi gen. nov., sp. nov. (Acari, Oribatida, Damaeidae) from Vietnam, with remarks on certain unusual diagnostic features, Zootaxa 4306 (3), pp. 370-382 : 371-378

Tamdamaeus staryi sp. nov.

( Figs 1–29 )

Diagnosis. Body size: 813–962 × 547–597. Four pairs of prodorsal tubercles developed (Da, Ba, Bp, La). Rostral and lamellar setae setiform, very long and strongly curved distally, slightly barbed. Interlamellar setae thickened, blunt-ended, barbed. Sensilli setiform, barbed, with attenuate tip. Spinae adnatae absent. Notogastral setae p 1– p 3 setiform, others thorn-like. Parastigmatic tubercles Sa triangular, Sp quadrangular. Epimeral tubercles (E2a, E2p, Va, Vp, VLa) well-developed. Epimeral setal formula: 3-1-3-4. Discidia tubercle-like. Anogenital setae setiform, slightly barbed. Formulas of leg segments (I–IV): femora: 7-6-6-6; genua: 4-4-3(or 4)-4; tibiae: 4-4-4-4; tarsi: 21- 18-18-15.

Description. Measurements. Body length: 813 (holotype, male), 846–962 (three paratypes, two females and one male); notogaster width: 547 (holotype), 564–597 (three paratypes). Females larger than males: 896, 962 × 581, 597 vs. 813, 846 × 547, 564.

Integument. Body color dark brown. Surface of body and legs with filamentous cerotegument, which is often absent, perhaps abraded. Rostral, lamellar and epimeral setae usually also with filamentous cerotegument.

Prodorsum ( Figs 1 , 3–6 , 13–16, 18, 19 ). Rostrum broadly rounded, with area of more translucent cuticle medially. Costulae (cos) and interlamellar ridges (ibr) well-developed. Translamellar lines absent. Tectum (apt) bent backwards laterally, interrupted medially. Anterobothridial ridges (abr) distinct, with slight thickening in the middle. Propodolateral apophyses (P) large, trapezoid, rounded distally. Anterolateral scales (sc) present above acetabula I, and indistinct tubercular thickenings (tub) developed below them. Four prodorsal tubercles present, Da, Ba and Bp rounded distally, La trapezoid. Rostral (ro, 127–139) and lamellar (le, 180–192) setae very long, setiform, slightly barbed, strongly curved distally. Interlamellar setae (in, 139–151) thickened, blunt-ended, barbed. Sensilli (bs, 298–303) setiform, slightly thickened proximally, with attenuate tip, barbed. Exobothridial setae (ex, 61–73) setiform, thin, slightly barbed.

Notogaster ( Figs 1 , 2 , 5, 7 , 13 , 14 , 20 ). Oval. Spinae adnatae absent. Dorsal notogastral setae inserted in two semi-circular rows, with tips radially oriented, c 1, c 2, la, lm (114–123), lp, h 3 (135–139), h 1, h 2 (155–164) of dark color, thickened, thorn-like, smooth or indistinctly roughened. Posterior setae p 1– p 3 (110–123) setiform, smooth. All lyrifissures (ia, im, ip, ih, ips) and opisthonotal gland openings (gla) distinct.

Gnathosoma ( Fig. 2 ). Typical for Damaeidae (e.g. Norton 1978; Ermilov & Kalúz 2013). Subcapitulum longer than wide (172–184 × 127–131). Subcapitular setae (h, 82–86; m, 65–73; a, 41–45) setiform, slightly barbed. Adoral setae (16) setiform, thin, smooth. Palps (164–172) with setation 0–2–1–3–9(+ω). Postpalpal setae (8) spiniform, smooth. Chelicerae (172–184) with two setiform setae, cha (53) barbed, chb (32–36) ciliate unilaterally in medio-distal part. Trägårdh’s organs elongate triangular.

Epimeral and lateral podosomal regions ( Figs 2 , 17 ). Parastigmatic tubercles Sa triangular, Sp quadrangular. Epimeral tubercles (E2a, E2p, Va, Vp, including in addition VLa) well-developed. Epimeral setal formula: 3–1–3– 4. Epimeral setae setiform, slightly barbed, 1a, 1b, 1c, 2a, 3a, 4a and 4b (61–73) shorter than other setae (106– 114). Discidia (dis) tubercle-like.

Anogenital region ( Figs 2 , 8 ). Six pairs of genital (g 1– g 6, 65–73), one pair of aggenital (ag, 69–77), two pairs of anal (an 1, an 2, 53–57) and three pairs of adanal (ad 1– ad 3, 86–90) setae setiform, slightly barbed. Adanal lyrifissures (iad) located in inverse apoanal position and close to anal aperture.

Legs ( Figs 9–14 , 21–29 ). All legs longer than body length ( Table 1). Claws smooth, slightly curved ventrodistally. Formulas of leg setation and solenidia: I (1–7–4–4–21) [1–2–2], II (1–6–4–4–18) [1–1–2], III (2–6– 3[or 4]–4–18) [1–1–0], IV (1–6–4–4–15) [0–1–0]; homologies of setae and solenidia indicated in Table 2. Setae d longer than σ on leg genua I–III. Large ventral tecta present on trochanters III and IV (vtIII, vtIV).

Type deposition. The holotype is deposited in the arachnological collection of the Senckenberg Museum für Naturkunde, Görlitz, Germany . Three paratypes are deposited in the collection of the Tyumen State University Museum of Zoology , Tyumen, Russia .

Etymology. The species name is dedicated to our colleague and well-known acarologist Dr. Josef Starý (Biology Centre v.v.i., Academy of Sciences of the Czech Republic, Institute of Soil Biology, České Budějovice, Czech Republic) for his extensive contributions to our knowledge of oribatid mites, who also collected the material and provided it kindly for our study.

Differential diagnosis. The new species is unique in combination of characters. None of the species known from Asia or from other regions, displays similar traits, especially the femoral setation on leg III and IV differs remarkably in the new species. In addition, all similar species with lacking spinae adnatae (members of genus Tectodamaeus ) have very different leg setation on genu IV (only two setae versus four in T. staryi sp. nov.). Epidamaeus bomeensis ( Xie, Huang, Yan, Huang & Yang, 2012) , described originally sub Spatiodamaeus , the only species with similar setation of genua I-IV and also tibiae I-II, has strongly developed spinae adnatae and practically absent apophyses P. Moreover, prodorsal and epimeral tubercles are differently evolved and tubercles La are absent. General appearance of the new species is closest to some species of Damaeus , however from all of them it can be easily distinguished by the absence of spinae adnatae, in addition to femoral setation.

Figures

FIGURE 1. Tamdamaeus staryi sp. nov., adult: dorsal view (legs except some right basal parts not shown). Scale bar 100 µm.

FIGURE 2. Tamdamaeus staryi sp. nov., adult: ventral view (left palp and legs except some left basal parts not shown). Scale bar 100 µm.

FIGURES 3 – 8. Tamdamaeus staryi sp. nov., adult: 3 — right sensillus and interlamellar seta, lateral view; 4 — anterior part of prodorsum, lateral view (gnathosoma and leg I except basal part not shown); 5 — medio-basal part of prodorsum and anterior part of notogaster, dorsolateral view (legs I, II except basal part not shown); 6 — mediobasal part of prodorsum, laterofrontal view (leg I except basal part not shown); 7 — posterior part of notogaster, lateral view; 8 — anogenital region, lateral view. Scale bar 100 µm.

FIGURES 9 – 10. Tamdamaeus staryi sp. nov., adult: 9 — leg I, without trochanter, right, antiaxial view; 10 — leg II, without trochanter, right, antiaxial view. Scale bar 100 µm.

FIGURES 11 – 12. Tamdamaeus staryi sp. nov., adult: 11 — leg III, left, antiaxial view; 12 — leg IV, left, antiaxial view. Scale bar 100 µm.

FIGURE 13. Tamdamaeus staryi sp. nov., adult, microscope image: dorsal view.

FIGURE 14. Tamdamaeus staryi sp. nov., adult, microscope image: lateral view.

FIGURES 15 – 29. Tamdamaeus staryi sp. nov., adult, microscope images: 15 — prodorsal tubercles in basal part of prodorsum; 16 — prodorsal tubercle La, propodolateral apophysis and scale in laterobasal part of prodorsum; 17 — tubercles of epimeral region; 18 — propodolateral apophysis; 19 — prodorsal tubercle La; 20 — notogastral seta h 2; 21 – 24 — basal parts of solenidia on tibiae I – IV, respectively; 25 – 28 — basal parts of solenidia and coupled setae d on genua I – IV, respectively; 29 — leg claw III. Scale bar 100 µm.