Peloribates spiniformis, Ermilov & Anichkin, 2011

Ermilov, S. G. & Anichkin, A. E., 2011, TWO NEW SPECIES OF ORIPODOIDEA (ACARI: ORIBATIDA) FROM VIETNAM Sergey G. E and Alexander E. A, Acarologia 51 (2), pp. 143-154 : 144-146

Peloribates spiniformis n. sp.

( Figures 1 – 3 )

With characters of Peloribates as summarized by Corpuz-Raros (1981) and Balogh and Balogh (1984, 1992).

Diagnosis

This species is characterized by the following combination of traits: body size 332 – 348 x 182; body surface foveolate; interlamellar setae medio-distally dilated, barbed; sensilli with long stalk and oblong head, rounded distally, with small barbs; 14 pairs of short, spiniform, straight, smooth notogastral setae; claws of legs finely serrated on dorsal edges.

Description

Measurements — Body length 340 (holotype), 332 – 348 (mean 337, three paratypes); body width 182 (holotype), 182 (three paratypes).

Integument — Body color light brown to brown. Surface of body, leg femora and trochanters III, IV foveolate. Foveolae oval or round (up to 10 in length or diameter) ( Figure 4 ).

Prodorsum — ( Figure 1A ; Figure 2A–F ). Rostrum broadly rounded anteriorly. Lamellae longer than half of prodorsum, distally with weakly developed lateral tooth. Rostral (ro, 41 – 45) and lamellar (le, 53 – 61) setae setiform, barbed. Interlamellar setae (in, 20) medio-distally dilated, barbed. Exobothridial setae (ex, 8) setiform, slightly thickened, barbed. Sensilli (ss, 52 – 60) with long stalk (28 – 32) and oblong head (24 – 28), rounded distally, with small barbs.

Notogaster — ( Figure 1A ). Dorsosejugal suture weakly developed, hardly visible. Pteromorphae short, movable. Fourteen pairs of short (4 – 6), spiniform, straight, smooth notogastral setae. Four pairs of minute sacculi, visible with difficulty. Opisthonotal gland opening (gla) and lyrifissures developed in typical arrangement for genus.

Lateral part of body — ( Figure 2A ). Tutorium (tu) long. Sublamellar line weakly developed. Sublamellar areae porosae (Al, 8 – 10) rounded or oval. Pedotecta I and II small. Discidia (di) triangular.

Anogenital region — ( Figure 1B ; Figure 2G, H ). Two pairs anal (an 1, an 2, 4), three pairs adanal (ad 1 – ad 3, 4 – 6), one pair aggenital (ag, 4 – 6) and five pairs of genital setae (g 1 – g 5 4) slightly thickened, smooth. Lyrifissures iad in typical position for genus.

Epimeral region — ( Figure 1B ). Apodemes 2, sejugal, 3 and circumpedal carina well-developed. All epimeral setae setiform, weakly barbed; setae 3c longest (24), 3a shortest (6).

Gnathosoma — ( Figure 3A–C ). Subcapitulum longer than wide: 69 – 73 x 57 – 61. Hypostomal setae setiform, barbed, different little in length (12 – 16). Lateral lips with two pairs of adoral setae (6 – 8), setiform, barbed. Palps (length 53 – 61) with setation 0-2-1-3-9(+1 ω). All setae (except some on tarsi) barbed. Chelicerae (length 73 – 82) chelatedentate; cheliceral setae setiform, barbed, cha (20 – 24) longer than chb (12 – 16).

Legs — ( Figure 3D–F ). Morphology similar to other species of Peloribates ( Beck 1964; Bayartogtokh 2000; Bayartogtokh and Smelyansky 2008). Tarsi with three claws, weakly serrated on dorsal sides; median claw thicker than lateral claws. Formulae of leg setation and solenidia: I (1-5-3-4-19) [1-2-2], II (1-5-3-4-15) [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. All setae barbed or with short cilia. Famulus short, straight, blunt-ended. Solenidia ω 1 on tarsi I, ω 1 and ω 2 on tarsi II, σ on genua II and III rod-shaped; other solenidia setiform.

Material examined — Holotype (female), paratypes (three specimens: two females and one male) were obtained from southern Vietnam, 11°25’ N, 107°25’ E, Cat Tien National Park, 149 m above sea level, in dark loamy soil of Lagerstroemia forest , February-March 2009, collected by A.E. Anichkin.

Type deposition — The holotype is deposited in the collection of the Zoological Institute of the Russian Academy of Sciences, St. Petersburg, Russia; two paratypes are deposited in the collection of the Center for Biodiversity Resources Education and Development (CEBRED), Hanoi National University of Education, Hanoi, Vietnam; one paratype is in the personal collection of the first author (Center of Independent Examinations–NN, Nizhniy Novgorod, Russia).

Etymology — The specific name " spiniformis " refers to the spiniform notogastral setae.

Distribution. — At present, this species is only known from Cat Tien National Park of southern Vietnam.

Comparison — Peloribates spiniformis n. sp. can be included in the Peloribates species group with very short notogastral setae ( P. alaskensis Hammer, 1955 from Alaska, P. asejugalis ( Pandit and Bhattacharya, 1999) from India, P. canadensis Hammer, 1952 from the Nearctic region, P. decumanus ( Berlese, 1908) from Brazil, P. glaber Mihelˇciˇc, 1956 from the Mediterranean region, P. peloptoides ( Berlese, 1888) from the Neotropical region, P. pseudoporosus Balogh and Mahunka, 1967 from Vietnam, P. tunisiensis Mahunka, 1980 from the Mediterranean region). However, it clearly differs from all species in this group by having interlamellar setae that are mediodistally dilated (setiform or spiniform in the other species).

Figures

FIGURE 1: Peloribates spiniformis n. sp. A – dorsal view, legs removed; B – ventral view, legs, palps and setae of subcapitulum removed. Scale bar 100 µm.

FIGURE 2: Peloribates spiniformis n. sp. A – lateral view of prodorsum, legs, gnathosoma and epimeral setae removed; B – foveolae of anterior part of prodorsum; C – rostral setae; D – lamellar seta; E – interlamellar seta; F – sensillus; G – genital plate, right; H – anal plate, right. Scale bar (A) 50 µm, scale bars (B, E) 10 µm, scale bars (C+D, F, G, H) 20 µm.

FIGURE 3: Peloribates spiniformis n. sp. A – subcapitulum; B – palp; C – chelicera; D – leg I, left, antiaxial view; E – femur and genu of leg II, right, antiaxial view; F – leg IV, right, antiaxial view. Scale bars 20 µm.

FIGURE 4: Zygoribatula prima n. sp. A – dorsal view, legs removed; B – ventral view, legs and gnathosoma removed. Scale bar 100 µm.