Euscheloribates guitingensis, Ermilov K & K, 2022

Ermilov K, Sergey G. & K, Leonila Corpuz- Raros, 2022, Two new species of Euscheloribates (Acari, Oribatida, Scheloribatidae) from the Philippines, Acarologia 62 (3), pp. 811-820 : 812-816

Euscheloribates guitingensis n. sp.

Zoobank: 6CD7359C-86AF-471D-8E7F-6C920A485421

( Figures 1 a-c; 3a, c, e-g; 4a-d)

Diagnosis — Body length: 249–282. Notogaster, epimeral and anogenital regions partially with sparse foveolae. Rostrum with two incisions. Translamella represented by two short ridges directed backwards. Tutorium present. Rostral and lamellar setae long, setiform, slightly barbed; interlamellar seta long, setiform, erect, barbed; ro shortest, le longest. Bothridial seta with short stalk and elongate clavate, slightly barbed head. Anterior notogastral margin distinctly convex medially. All notogastral setae short, setiform, slightly flexible, smooth. Epimeral and anogenital setae short, setiform, smooth; both aggenital setae present; each anal plate with one seta. Circumpedal carina long. Leg tarsus I with 16 setae, tarsus III with 13 setae, trochanter III with one seta, genua IV with one seta.

Description of adult — Measurements – Body length: 282 (holotype, female), 265–282

(four paratype females), 249 (three paratype males); body width: 149 (holotype), 140–157

(four paratype females), 123–132 (three paratype males).

Integument – Body color brown. Cuticle microporose (visible in dissected specimens under high magnification, ×1500). Notogaster (except median and lateral part), epimeral region and partially anogenital region sparsely foveolate (diameter of foveola up to 2).

Prodorsum – Rostrum with two incisions. Lamella about 1/2 length of prodorsum. Prolamella lineate. Sublamella about 2/3 length of prodorsum. Sublamellar porose area rounded (4–6) or oval (6–8 × 4). Translamella absent, only two short ridges developed near lamellae, directed backwards. Tutorium medium-sized, simple. Rostral (22–24) and lamellar (34–36) setae setiform, slightly barbed. Interlamellar seta (28–30) setiform, erect, barbed. Exobothridial seta represented by alveolus. Bothridial seta (24–30) with short (4–6), smooth stalk and longer (18–24), elongate clavate, slightly barbed head. Bothridium with lateral scale. Dorsosejugal porose area oval (6 × 2–4). Dorsophragma distinctly elongate.

Notogaster – Anterior notogastral margin distinctly convex medially. Ten pairs of notogastral setae (14–16) setiform, thin, slightly flexible, smooth. Four pairs of sacculi drop-like; S3 smallest, sometimes poorly visible. Opisthonotal gland opening and all lyrifissures distinct.

Gnathosoma – Subcapitulum size: 65–69 × 45–49; subcapitular (a: 12; m, h: 16) and adoral (6) setae setiform, roughened. Palp (length: 41–45) setation: 0–2–1–3–9 (+ω); solenidion swollen distally. Postpalpal seta (4) spiniform, smooth. Chelicera (length: 65–69) with two setiform, barbed setae cha (: 24; chb: 14–16).

Epimeral and lateral podosomal regions – Epimeral formula: 3–1–2–2; setae (c: 4; others: 10–12) setiform, thin, smooth. Humeral porose area Ah distinct; Am not observed. Pedotecta I,

II represented by small laminae; pedotectum II rounded distally in ventral aspect. Discidium triangular, rounded distally. Circumpedal carina comparatively long, anteriorly reaching pedotectum II.

Anogenital region – Three pairs of genital (10–12), one pair of aggenital (10–12), one pair of anal (10–12), and three pairs of adanal (12–14) setae setiform, thin, smooth. Adanal lyrifissure distinct. Marginal porose area not observed. Ovipositor elongated (85 × 24), blade (32) shorter than length of distal section (beyond middle fold; 53); each of the three blades with four smooth setae, ψ 1 ≈ τ 1 (20) setiform, ψ 2 ≈ τ a ≈ τ b ≈ τ c (8) slightly thorn-like; six coronal setae (4) spiniform.

Legs – Claw slightly barbed on dorsal side. Porose area on all femora and on trochanters III, IV well visible; porose area on all tarsi and tibiae absent. Formulas of leg setation and solenidia: I (1–5–2–4–16) [1–2–2], II (1–5–2–4–15) [1–1–2], III (1–2–1–3–13) [1–1–0], IV (1–2–1–3–12) [0–1–0]; homology of setae and solenidia indicated in Table 1. Famulus short, slightly swollen distally, inserted posterior to solenidion 2 ω; seta d on femora III, IV inserted dorsobasally on segments. Solenidion ω 1 on tarsus I, ω 1 and ω 2 on tarsus II and σ on genu III slightly bacilliform; other solenidia setiform.

Material examined — Holotype (female) and seven paratypes (three males and four females): Philippines, Sibuyan Is., Romblon Province, Mt. Magdiwang, Mount Guiting-guiting Natural Park , leaf litter in forest (Museum number: JCBN 17 0330-2), 30.III.2017 (leg.

O.L. Eusebio).

Type deposition — The holotype is deposited in the collection of the Senckenberg Museum of Natural History, Görlitz, Germany ; seven 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.

Etymology — The species name guitingensis refers ro the place of origin, Mount Guiting-guiting Natural Park.

Remarks — Euscheloribates guitingensis n. sp. is morphologically most similar to Euscheloribates olszanowskii Bayartogtokh & Shimano, 2020 from Palau in having aggenital setae, clavate bothridial seta with short stalk and one pair of anal setae. However, the new species differs from the latter by larger body size (length: 249–282 versus 203–208), in the presence (versus absence) of tutorium, two incisions on the rostrum and partial foveolate notogaster and ventral plate, and by reduced leg chaetome (e.g. tarsus I with 16 setae, tarsus III with 13 setae, trochanter III and genua IV with one seta versus tarsus I with 19 setae, tarsus III with 15 setae, trochanter III and genua IV with two setae).

Figures

Figure 1 Euscheloribates guitingensisn. sp., adult: a – dorsal view (legs omitted); b – ventral view (gnathosoma and legs omitted); c – lateral view (gnathosoma and legs omitted). Scale bar 60 μm.