Ceratorchestes (Ceratorchestes) duocornutus, Ermilov, 2024

Ermilov, Sergey G., 2024, New Ceratorchestes (Acari, Oribatida, Peloppiidae) from Venezuela, Zootaxa 5506 (4), pp. 555-566 : 559-561

Ceratorchestes (Ceratorchestes) duocornutus sp. nov.

( Fig. 3 )

Material. Holotype (female) and two paratypes (two males): northern Venezuela, Aragua State, Rancho Grande , 1450 m a.s.l., leaf litter, 26.II.1995 ( R. W. Brooks).

The holotype is deposited in the collection of the Canadian National Collection, Ottawa, Canada; two paratypes are deposited in the collection of the Tyumen State University Museum of Zoology , Tyumen, Russia. All specimens are preserved in 70% solution of ethanol with a drop of glycerol.

Diagnosis. Body length: 375–390. Rostrum tripartite; rostral protrusions triangular, simple, similar in size. Lateral tooth of prodorsum strong. Lamellar cusp with well-developed lateral tooth and oblique medial part; translamella absent. Rostral and lamellar setae medium-sized, setiform, barbed; interlamellar seta long, slightly thickened, stiff, acuminate, barbed; bothridial seta long, setiform, shortly ciliated. All notogastral setae (except minute c) slightly thickened, stiff, acuminate, barbed; p 1 – p 3 shorter than others. Cheliceral seta cha comparatively short. Epimeral setae 1b, 1c, 3b medium-sized, longer than others, slightly thickened, stiff, acuminate; 3a inserted in the same oblique row with setae of epimere IV. Adanal lyrifissure oblique to anal plate. Leg trochanter IV rounded dorsoanteriorly.

Description of adult. Measurements. Body length: 390 (holotype), 375 (male paratypes); body width: 285 (holotype), 270 (male paratypes).

Integument. Body color light brown. Surface densely microgranulate sculpturing (visible only under high magnification in dissected specimens; × 1000); lateral part of prodorsum between bothridium and acetabula I–III with larger granules (diameter up to 1).

Prodorsum ( Figs 3A, C ). Rostrum tripartite; all rostral protrusions triangular, slightly rounded apically, similar in size. Lateral tooth of prodorsum tp strong. Lamella about 2/3 length of prodorsum; lamellar cusp with well-developed lateral tooth and oblique medial part; translamella absent; sublamella not observable. Rostral (34–37) and lamellar (45–49) setae setiform, barbed; rostral seta inserted medial to tutorial end and distanced from it; interlamellar seta (75–79) slightly thickened, stiff, acuminate, barbed; bothridial seta (94–101) setiform, shortly ciliated; exobothridial seta (26–30) setiform, thin, roughened.

Notogaster ( Figs 3A, C ). Anterior notogastral margin convex medially. Notogastral seta c (4) needleform; other notogastral setae (la, lm, lp, h 1 – h 3: 86–94; p 1 – p 3: 71–75) slightly thickened, stiff, acuminate, barbed. Opisthonotal gland opening and all lyrifissures well observable.

Gnathosoma . Similar to C. (C.) tripartitus sp. nov. Subcapitulum size: 97–105 × 86–90; subcapitular setae a, m (22–26) setiform, roughened; h (32–37) slightly thicker, setiform, barbed; both adoral setae (7) setiform, thin, smooth. Palp length: 75–79; setation: 0-2-1-3-9 (+solenidion); postpalpal seta (6) spiniform, smooth. Chelicera length: 86–90; teeth of both digits small but well developed; setae (cha: 15; chb: 19) setiform, thin, roughened.

Epimeral and lateral podosomal regions ( Figs 3B, C ). Epimeral formula: 3-1-3-5; 1b, 1c, 3b (45–49) slightly thickened, stiff, acuminate, barbed; 3c (26–30), 4a, 4b, 4c (22–26) setiform, slightly barbed; 4d (34–37) setiform, barbed; 1a, 2a, 3a (13–15), 4e (22–26) setiform, thin, roughened; 3a noticeably distanced from 2a and inserted in the same oblique row with setae of epimere IV.

Anogenital region ( Figs 3B–D ). Anogenital formula: 6-1-2-3; genital setae (g 1: 15–19; g 2 – g 6: 11–15) setiform, roughened; aggenital (30–34), anal (28–30) setae and adanal setae ad 2 (34–37), ad 3 (30–34) setiform, barbed; adanal seta ad 1 (52–56) slightly thickened, stiff, acuminate, barbed. Genital and anal plates in females noticeably larger than in males. Adanal lyrifissure close and oblique to anal plate.

Legs. Similar to C. (C.) tripartitus sp. nov.

Remarks. The new species is similar to C. (C.) baloghi Mahunka, 1983 (see also Mahunka 1982) and C. (C.) cornutus Mahunka, 1982 in the absence of the translamella, but differs from both by the morphology of the rostrum (tripartite versus pointed) and lamellar cusp (with strong lateral tooth versus truncate).

Etymology. The specific epithet duocornutus refers to the presence of one pair of the well-developed teeth on lateral parts of the prodorsum.

Figures

FIGURE 3. Ceratorchestes (Ceratorchestes) duocornutus sp. nov., adult, male (A, B) and female (C, D): A—dorsal view (legs omitted); B—ventral view (legs omitted); C—right lateral view (gnathosoma and legs omitted); D—anogenital region. Scale bar 100 μm.