Roynortonia vietnamica, Ermilov, 2011

Ermilov, S. G., 2011, A New Genus And Species Of Amerobelbidae (Acari: Oribatida) From Vietnam, Acarologia 51 (3), pp. 275-282 : 278-281

Roynortonia vietnamica n. sp.

( Figures 1 – 3 )

Diagnosis

Body size 196 – 229 x 108 – 123; rostral and lamellar setae short, minute barbed; interlamellar setae long, barbed. Bothridial projections long, rigid, directed posterolaterally, 20 – 24, smooth. Notogastral spines very short (2 – 4), conical. Notogastral setae, 10 pairs, heterotrichous: anterior five pairs of medium long, posterior five pairs shorter. Setae 3b (41), thorn-like.

Description

Measurements — Body length 217 (holotype, male), 196 – 229 (six paratypes; two males and four females); body width 114 (holotype, male), 108 – 123 (six paratypes; two males and four females).

Integument — Body color light brown. Surface of body smooth. Granular and cloud-like cerotegument covers lateral parts of body and regions of dorsosejugal scissure and sejugal apodemes. Granules very small (diameter less than 1 µm).

Prodorsum — ( Figure 1A, C ; Figure 2A–D ). Rostral and lamellar setae 10 – 12, minute barbed. Interlamellar setae 36 – 45, barbed. Sensilli long, 57 – 65, setiform, with more than 20 cilia unilaterally. Bothridial projections long, rigid, directed posterolaterally, 20 – 24, smooth. Exobothridial setae very short (4), thin, smooth.

Notogaster — ( Figure 1A, C ; Figure 2D ). Notogastral spines very short (2 – 4), conical. Notogastral setae with indistinct barbs; setae c, la, lm, lp and h 3 (24 – 28) longer than others (12 – 16). Notogastral setae inserted on all notogaster surface. All lyrifissures and opisthonotal gland opening distinct; lyrifissures ia located posteriorly to notogastral spines.

Anogenital region — ( Figure 1B, C ; Figure 2E, F ). Two pairs anal (an 1, an 2, 10 – 12), three pairs adanal (ad 1 - ad 3, 12 – 20), one pair aggenital (ag, 10 – 20) and six pairs genital (g 1 - g 6, 4 – 6) setae setiform, smooth. Lyrifissures iad in direct apoanal position.

Epimeral region — ( Figure 1B, C ; Figure 2G ). Only apodemes 1, 2 and complete sejugal apodeme well-developed. Setae 3b longest (41), thorn-like, smooth, inserted on large apophyses; setae 1a, 2a, 4a shortest (12 – 16), setiform, slightly barbed; other setae 20 – 32, setiform, with short barbs.

Gnathosoma — ( Figure 2H–J ). Subcapitulum longer than wide (45 – 49 x 32 – 34). Hypostomal setae setiform, smooth; h (8 – 10) little longer than m (6 – 8) and a (6). One pair of adoral setae (or 1, or 2) minute (1). Palp (length 32) with setation 0-2-1- 3-9(+1ω). Solenidion pressed to surface of palptarsus. Chelicera (57) chelate-dentate. Cheliceral setae setiform, barbed; cha (18) longer, than chb (12).

Legs — ( Figure 3A–D ). Formulae of leg setation including famulus and solenidia (in square brackets): I (1-5-3-4-20) [1-2-2], II (1-5-3-4-16) [1-1-2], III (2-3-1-3-15) [1-1-0], IV (2-3-2-3-12) [0-1-0]; homology of setae and solenidia indicated in Table 1. All setae setiform. Famulus short, conical. Solenidia ω 1 on tarsi I, ω 1 and ω 2 on tarsi II, σ on genua III thickened, rod-like; solenidia ω 2 on tarsi I, ’ 1 and ’ 2 setiform; other solenidia thickened, strongly curved in median part.

Material examined — Holotype (male) and one paratype (male) were obtained from Cat Tien National Park, in southern Vietnam, 11°25’ N, 107°25’ E, 149 m a.s.l., in dark loamy soil of Lagerstroemia forest, February-March 2009, collected by A.E. Anichkin. Five paratypes (one male and four females) were obtained ibid, but: 11°26’ N, 107°25’ E, 145 m a.s.l., 20 November 2006, collected also by A.E. Anichkin.

Type deposition — The holotype is deposited in the collection of the Center for Biodiversity Resources Education and Development ( CEBRED), Hanoi National University of Education , Vietnam ; four paratypes are deposited in the collection of the Siberian Zoological Museum , Novosibirsk, Russia ; two paratypes (dissected) are in the personal collection of the author.

Etymology — The specific name " vietnamica " refers to the country of origin, Vietnam.

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

Figures

FIGURE 1: Roynortonia vietnamica n. sp.: A – dorsal view, legs not shown, B – ventral view, gnathosoma and legs partly not shown, C – lateral view, gnathosoma and legs partly not shown. Scale bar (A+B, C) 50 µm.

FIGURE 2: Roynortonia vietnamica n. sp.: A – rostral setae, B – interlamellar seta, C – sensillus, D – postbothridial and anterio-lateral notogastral regions, E – genital plate, left, F – anal plate, left, G – epimeral seta 3b, H – subcapitulum, I – palp, J – chelicera. Scale bar (A+B, C-G, I) 10 µm, scale bar (H, J) 20 µm.

FIGURE 3: Roynortonia vietnamica n. sp.: A – leg I, right, antiaxial view, B – leg II, right, antiaxial view, C – leg III, right, antiaxial view, D – leg IV, right, antiaxial view. Scale bar 20 µm.