Neophysobates incrassatus, Ermilov & Minor, 2015

Ermilov, S. G. & Minor, M. A., 2015, Two new species of Neophysobates (Acari, Oribatida, Tegoribatidae) from New Zealand, Acarologia 55 (3), pp. 285-295 : 290-294

Neophysobates incrassatus n. sp.

( Figures 4-5 )

Diagnosis — Body size: 196 – 217 × 115 – 147. Anterior margin of pteromorph and epimeral region striate. Rostral and lamellar setae thin, smooth. Bothridial seta fusiform, stalk with strong mid-length swelling. Tutorium ridge-like, curving backwards,

Roman letters refer to normal setae, Greek letters to solenidia (except ɛ = famulus). Single prime (') marks setae on anterior and double prime ('') setae on posterior side of the given leg segment. Parentheses refer to a pair of setae.

without free tip. Three pairs of notogastral porose areas. Five pairs of genital setae. Aggenital setae absent. Legs bidactylous.

Description — Measurements. Body length: 213 (holotype: male), 196 – 217 (nine paratypes: five females and four males); body width: 143 (holotype), 115 – 147 (nine paratypes). Without sexual dimor- phism.

Integument — Body color light brown to brown.

Body surface smooth, except anterior margins of pteromorph (with several transverse striae) and epimeral region (with numerous longitudinal striae). Cerotegumental microgranules absent.

Prodorsum — Rostrum rounded. Lamella covering entire prodorsum; no parts of pedotectum I visible in dorsal view. Rostral (8 – 10) and lamellar (10 – 12) setae setiform, thin, smooth. Bothridial seta (49 – 57) fusiform. Stalk with strong mid-length swelling (sw). Head elongated, slightly or distinctly pointed, barbed. Tutorium of medium width, ridgelike, curving backwards distally, without free tip anteriorly. Exobothridial seta and its alveolus not found.

Notogaster — Anterior margin straight. Ptero- morph broadly rounded, without teeth and incisions. Hinge clearly developed. Dorsophragmata of medium size, fused into narrowly tringular structure. Three pairs (in all specimens; A2 apparently absent) of rounded porose areas: Aa (8) larger than A1 and A3 (both 6). Ten pairs of short (2 – 4), thin, smooth notogastral setae. All lyrifissures and opisthonotal gland opening distinct.

Gnathosoma — Generally, similar to N. zealandicus n. sp. Subcapitulum longer than wide (53 – 57 × 45). Subcapitular setae setiform, smooth, a and m (both 6) little longer and thicker than h (4). Two pairs of adoral setae (4) thin, smooth. Axillary saccule elongated. Palp (34 – 36) with setation 0-2-1- 3-9(+ ω). Solenidion straight. Chelicera (53 – 57) with two barbed setae; cha (16) longer than chb (10). Trägårdh’s organ long, tapered.

Lateral podosomal and epimeral regions — Genal tooth narrowly triangular, long, reaching rostrum. Pedotectum I large, rounded anteriorly, pedotectum II small, scale-like in lateral view. Epimeral setal formula: 3-1-2-2; all setae short (4) thin, smooth. Custodium strong, directed anteriorly to the pedotectum II. Discidium triangular. Circumpedal carina distinct.

Anogenital region — Five pairs of genital, two pairs of anal and two pairs of adanal setae similar in length (4), thin, smooth. Aggenital seta absent. Lyrifissure iad long, about 1/4 length of anal plates, located in paraanal position. Ovipositor slightly elongated (52 × 41), lobe (32) distinctly longer than distal section (beyond middle fold; 20). Each of three lobes with four straight, smooth setae; ψ 1 ≈ τ 1 (16) longer than ψ 2 ≈ τa ≈ τb ≈ τc (12). Six pairs of coronal setae (8 – 10) straight, smooth, inserted in medial part of distal section.

Legs — Generally, similar to N. zealandicus n. sp. Heterobidactylous. Formulas of leg setation and solenidia: I (1-4-2-3-18) [1-2-2], II (1-4-2-4-15) [1-1-2], III (2-2-1-2-15) [1-1-0], IV (1-2-1-2-12) [0-1-0]; homology of setae and solenidia indicated in Table 2 . Seta pv” on tarsi II short, thick, thorn-like, with several strong spines.

Material examined — Holotype (male) and nine paratypes (five females and four males): New Zealand, South Island, Central Otago, Pisa Range , 44°52’11”S, 169°10’9”E, 1797 m a.s.l., in soil and debris under Raoulia sp. cushion plant (Compositae), 18 February 2014, collected by M. Minor.

Type deposition — The holotype (alcohol) and three paratypes (alcohol) are deposited in the New Zealand National Arthropod Collection, Auckland, New Zealand ; three paratypes (alcohol) are deposited in the collection of the Senckenberg Institution , Frankfurt, Germany ; three paratypes (alcohol) are deposited in the collection of the Tyumen State University Museum of Zoology , Tyumen, Russia .

Etymology — The specific name " incrassatus " refers to the mid-length swelling of bothridial setae.

Comparison — Neophysobates incrassatus n. sp. is similar to N. monodactylus in having bothridial seta with a mid-length swelling in medial part of the stalk and in having five pairs of genital setae. However, it differs from the latter by the presence of bidactylous legs (vs. monodactylous), three pairs of notogastral porose areas (vs. four), rostral setae thin, similar to lamellar setae in thickness (vs. thicker than lamellar setae), and tutorium without free tip (vs. with knife-like tip). The three known species of Neophysobates can be distinguished by the key presented below.

Figures

FIGURE 4: Neophysobates incrassatus n. sp.: A – dorsal view; B – ventral view (gnathosoma and legs not illustrated); C – posterior view. Scale bar 50 µm.

FIGURE 5: Neophysobates incrassatus n. sp.: A – antero-medial part of prodorsum, dorso-frontal view; B – anterior part of body, lateral view; C – bothridial seta; D – right half of subcapitulum, ventral view; E – genu, tibia and tarsus of leg II, right, paraxial view. Scale bar (A, B) 50 µm, scale bar (C-E) 20 µm.