Scheloribates (Hemileius) dianae, Ermilov & Subías & Shtanchaeva & Friedrich, 2021

Ermilov, Sergey G., Subías, Luis S., Shtanchaeva, Umukusum Ya. & Friedrich, Stefan, 2021, New sacculonotic Oripodoidea (Acari: Oribatida) from Peru, Zootaxa 5048 (3), pp. 422-434 : 427-430

Scheloribates (Hemileius) dianae sp. nov.

( Figs 3 , 4 )

Diagnosis. Body size: 365–498 × 215–282. Rostrum rounded. Prolamella complete. Translamella absent. Rostral, lamellar and interlamellar setae long, setiform, barbed; ro shortest. Bothridial seta long, narrowly spindleform, with setiform apical tip, unilaterally ciliate. Anterolateral part of notogaster with triangular process. Notogastral setae setiform, smooth; c, la, lm, and lp long, other setae of medium length. Epimeral and anogenital setae short, setiform, barbed. Circumpedal carina short. Leg tarsus I with 19 setae (l” absent); genu II with two setae (v’ absent).

Description of adult. Measurements. Body length: 464 (holotype: female), 365–498 (17 paratypes: eight males and nine females); body width: 265 (holotype), 215–282 (17 paratypes). No differences between males and females in body size.

Integument. Body color brown. Cuticle microporose (visible under high magnification, ×1000). Lateral side of body with microgranulate cerotegument between bothridium and acetabula I–IV.

Prodorsum ( Figs 3A, C ). Rostrum rounded. Lamella about 1/2 length of prodorsum. Prolamella complete. Sublamella linear, similar to lamella in length. Sublamellar porose area (4–6) rounded. Translamella absent. Lateral keel-shaped ridge distinct. Rostral (69–73), lamellar (102–106) and interlamellar (102–106) setae setiform, barbed. Exobothridial seta (32–36) setiform, slightly barbed. Bothridial seta (106–110) narrowly spindleform, with setiform apical tip, unilaterally shortly ciliate. Dorsosejugal porose area not observed.

Notogaster ( Figs 3A, C ). Anterolateral part of notogaster with triangular process. All notogastral setae (c, la, lm, lp: 61–73; others: 32–36) setiform, smooth. Four pairs of small sacculi. Opisthonotal gland opening and all lyrifissures distinct.

Gnathosoma ( Figs 4A–D ). Subcapitulum longer than wide (102–106 × 73–86). All subcapitular (a: 20; m: 14–16; h: 24) and adoral (10–12) setae setiform, barbed; m thinner than a and h. Palp (65–69) with typical setation: 0-2-1-3-9 (+ω). Postpalpal seta (6) spiniform, roughened. Chelicera (106–110) with two setiform, barbed setae (cha: 32–36; chb: 20–24).

Epimeral and lateral podosomal regions ( Figs 3B, C ). Epimeral setal formula: 3-1-3-3. All setae setiform; 4a and 4b (16) slightly barbed, 1a, 2a and 3a (20) heavily barbed, 1b, 1c, 3b, 3c, and 4c (24–28) barbed. Pedotectum II with rounded lateral part. Discidium triangular, rounded apically, seta 4c inserted on its dorsal side. Circumpedal carina comparatively short, posteriorly not reaching ventral plate, anteriorly not reaching pedotectum II.

Anogenital region ( Figs 3B, C ). Genital (g 1: 20; others: 14–16), aggenital (16), anal (14–16), and adanal (20) setae setiform, barbed. Adanal lyrifissure distinct. Marginal porose area band-like, complete.

Legs ( Figs 4E–H ). Tridactylous; all claws slightly barbed on dorsal side; lateral claws thinner median claw, with small tooth distoventrally. Femur II with broadly rounded ledge distoventrally. Dorsoparaxial porose area on femora I-IV and on trochanters III, IV, proximoventral porose area on tarsi I-IV and distoventral porose area on tibiae I-IV well visible. Formulas of leg setation and solenidia: I (1-5-3-4-19) [1-2-2], II (1-5-2-4-15) [1-1-2], III (2-3-1-3-15) [1-1-0], IV (1-2-2-3-12) [0–1–0]; homology of setae and solenidia indicated in Table 1 . Famulus of tarsus I short, erect, slightly swollen distally, inserted between solenidion ω 2 and seta ft”. Solenidion ω 1 on tarsi I, ω 1 and ω 2 on tarsus II and σ on genu III bacilliform, other solenidia setiform. Seta s on tarsus I setiform, barbed (not eupathidial), inserted behind setae a’ and a”.

Type deposition. The holotype is deposited in the collection of the MUSM ; 17 paratypes are deposited in the collection of the TSUMZ. All specimens are preserved in 70% solution of ethanol with a drop of glycerol.

Etymology. The specific name dianae is given in honour of Dr. Diana Silva Dávila, head of the arachnological department of the Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima, Peru for her always kind and valuable help and cooperation.

Remarks. In having narrowly spindleform bothridial seta with setiform apical tip, the new species is similar to Scheloribates (Hemileius) muscicola ( Hammer, 1961) from Peru, but it differs from the latter by the smaller body length (365–498 versus 600), presence (versus absence) of anterolateral triangular notogastral processes and long (versus represented by alveoli) notogastral setae.

Figures

FIGURE 3. Scheloribates (Hemileius) dianae sp. nov., adult:A—dorsal view; B—ventral view (gnathosoma and legs omitted); C—lateral view (gnathosoma and legs omitted). Scale bar 100 μm.

FIGURE 4. Scheloribates (Hemileius) dianae sp. nov., adult: A—subcapitulum, ventral view; B—right lip with adoral setae, ventral view; C—palp, left, paraxial view; D—chelicera, left, paraxial view; E—leg I, right, antiaxial view; F—leg II (tarsus omitted), right, antiaxial view; G—leg III (tarsus omitted), left, antiaxial view; H—leg IV, left, antiaxial view. Scale bars 20 μm (A, B, D–H), 10 μm (C).