Oziella virgata, Chetverikov, Philipp E., 2016

Chetverikov, Philipp E., 2016, New species and records of phytoptid mites (Acari: Eriophyoidea: Phytoptidae) on sedges (Cyperaceae) from the Russian Far East, Zootaxa 4061 (4), pp. 367-380 : 374-377

Oziella virgata n. sp.

( Figs. 2 , 5 & 6 )

HOLOTYPE FEMALE. Idiosoma vermiform, 328, 61 wide. Prodorsal shield subtriangular, with anterior margin weakly rounded and slightly indented medially. Prodorsal shield ornamentation consisting of a median, two admedian, four to five submedian and two transverse arc-like lines. Median line straight, entire, visible in posterior two-thirds of shield; both admedian lines straight in anterior third of shield and slightly sinuous in posterior twothirds, together forming a bottle-like figure, usually with a gap in anterior one-third of prodorsal shield. Submedian-1 line interrupted in middle third and thus consists of two parts (anterior and posterior). Posterior part of submedian-I resembles a short curved line between tubercle of sc and posterior portion of admedian line. This arc-like line extends from admedian lines between two parts of submedian-I joining one of the incomplete epicoxal annuli. Submedian-2,3,4 lines short, visible in anterior one-third of prodsorsal shield. Indistinct eye-like area of flat cuticle (“eye-like structure” sensu Smith 1977) laterally to ve present. Granulation on surface of prodorsal shield anterior to ve present. Prodorsal shield 31, 48 wide; ve 12, directed forward and slightly laterally; tubercles 28 apart; sc 2 long, directed upward, tubercles 18 apart. Distance between tubercles of ve and sc 16. Gnathosoma 23. Dorsal pedipalp genual setae d 10, pedipalp coxal setae ep not apparent in all observed specimens, probably situated on inner surface of palps. Leg I 29, tibia 6, l' 2, tibial solenidion φ 7; tarsus 6, u' 2, rod-like with or without tiny knob; ft' 8, ft'' 28, ω 9, without knob; empodium 10/9-rayed, 12 long; bv 7. Leg II 24, tibia 6, tarsus 5, u' 2, rod-like with or without tiny knob; ft' 10, ft'' 25, ω 8, without knob; empodium 10/9-rayed, 11; bv 6. Coxae without microtubercles, only thin longitudinal and less numerous transversal lines present. Subcapitular plate rounded, flat. Setae 1b 14, 16 apart; 1a 21, 12 apart; 2a 32, 27 apart. Prosternal apodeme well developed, divided anteriorly and three-forked posteriorly. Epigynium 11, 20 wide, flat; 3a 9; two complete and two incomplete annuli present anterior to epigynium. Opisthosoma with 86 ventral and 90 dorsal annuli bearing elongated, ellipsoidal microtubercules. Setal lengths: c1 60, c2 48, d 45, e 4, f 53, h1 3; 10 annuli between rear shield margin and c1 tubercles, 9 annuli from rear prodorsal shield margin to c2; 14 annuli between c2 and d, 25 annuli between d and e, 26 annuli between e and f, and 12 annuli between f and h1.

MALE (n=5). Similar in shape to female; about 0.9 times size of female. Prodorsal shield ornamentation and chaetotaxy similar to female. Eugenital setae not visible either with conventional optical microscope or in CLSM. Gonopore flanked anteriorly with thin plate-like genital coverflap. All measurements of males are given in Table 1 .

NYMPH (n=3). Idiosoma wormlike, 264–283 long. Prodorsal shield ornamentation similar to female but less distinct. Leg I 21–23 long, empodia 8/7-rayed. Opisthosoma with 77–82 dorsal annuli and 76–83 ventral annuli. In contrast to adult which have 2–3 complete and 2–3 incomplete annuli before epigynium or epiandrium; nymphs of O. virgata n. sp. possess an average 12–13 complete annuli and a scattered granules (instead of incomplete annuli) before setae 3a ( Fig. 5 F). Position of 3a relatively setae c2 also differs: in nymphs 3a and c2 are situated at same level whereas in immatures 3a situated 2–3 annuli ahead to c2. All measurements of nymphs are given in Table 1 . Host plant. Carex appendiculata (Trautv. & C.A.Mey.) Kükenthal 1903 (Cyperaceae) .

Relation to the host plant. The mites were found living inside the leaf sheaths, causing no apparent damage.

Type material. Female holotype (slide ##K-5-06/1), 11 female paratypes, 4 nymph larvae (slides #K-4-06/1, #K-4-06/2, #K-5-06/1, #K-5-06/2). Slides #K-4-06/1, #K-4-06/2, are deposited in Saint-Petersburg State University, Department of Invertebrate Zoology (Universitetskaya naberejnaya, 7/9, Saint-Petersburg, 199034, Russia); slides #K-5-06/1, #K-5-06/2 are deposited in the Acarological Collection of the Zoological Institute of Russian Academy of Sciences ( ZIN RAS). All specimens collected from RUSSIA: Kamchatka Peninsula, Yelizovsky Municipal District, near settlement Noviy ( Fig. 1 D); from Carex appendiculata , in a swamp near Avacha River, 25 August 2006, coll. P.G. Efimov.

Additional identified material. Three males, two females and one nymph on two slides (#316-12 and #317- 12) collected from RUSSIA: Kamchatka Peninsula, Kronotsky Nature Reserve, Uzon volcanic caldera ( Fig. 1 C), from leaf sheaths of Carex appendiculata , 28 August 2012, coll. D.E. Gimelbrant. Numerous mites (all stages) accompanied with Novophytoptus rostratae Roivainen 1947 , on five slides (#190-12, #191-12, #192-12, #193-12, #194-12) collected from RUSSIA: the Sakha Republic (Yakutia), Oymyakonsky Ulus, south coast of Labynkyr Lake ( Fig. 1 A), same host and relation to host, 5 July 2012, coll. S. Aibulatov.

Distribution. Oziella virgata n. sp. is at present recorded from the Russian Far East (The Sakha Republic and Kamchatka Peninsula). However, Carex appendiculata , the host plant of O. virgata n. sp., is widely distributed from Siberia to Korea, in Papua New Guinea and the Hawaiian Islands, so future surveys could reveal a much wider distribution for this new mite species.

Etymology. The specific epithet, virgata , is a feminine singular adjective derived from the Latin word virga (rod), referring to the uncommon shape of seta u' in this species.

Differential diagnosis. The new species possesses a unique rod-shaped seta u', not recorded previously in the Eriophyoidea . Apart from this, O. virgata n. sp. is close to Oziella atherodes ( Chetverikov 2011) but can be easily distinguished by the ornamentation of the prodorsal shield and notably shorter tarsal solenidia ω, c1 and e ( Table 3).

Character Oziella species

O. virgata n. sp. O. atherodes Median line of prodorsal shield Incomplete Complete Short lines flanking median line near posterior shield margin Absent Present Arc-like transverse line of prodorsal shield Present Absent Length of ω I 8 (8–9) 12 (11–15) Length of ω II 8 (8–9) 13 (12–15) Length of c1 59 (55–65) 113 (100–125) Length of e 4 (3–5) 11 (9–15)

Figures

FIGURE 1. Findings of Oziella virgata n. sp. (A, C, D) and Oziella ovalis n. sp. (B) in the Russian Far East. Note: This slightly cropped map shows the location of the Far Eastern Federal District of Russia (highlighted) based on: en. wikipedia. org / wiki / Russian _ Far _ East.

FIGURE 2. Semi-schematic drawings Oziella virgata n. sp. females (A – F) and Oziella ovalis n. sp. (G – L). Prodorsal shield (A, L), coxigenital area (B, K), Leg I (D, G), Leg II (C, H), empodium I (E, I), tarsal solenidion I (F, J). Scale bar: A = 25 µm; B = 20 µm; C, D, G, H = 30 µm; E, F, I, J = 10 µm; K = 30 µm; L = 25 µm. Notations: adm — admedian line; sm 1 – 5 — submedian lines 1 to 5 correspondingly.

FIGURE 5. CLSM images of Oziella virgata n. sp. A, B, C, D — four images showing variation of the prodorsal shield ornamentation; E — female external genitalia; F — nymph coxigenital area; G — male coxigenital area; H — male external genitalia; I — spermathecal apparatus. Scale bar: A, B, C, D = 15 µm; E, F, G, H, I = 10 µm.

FIGURE 6. Microphotographs of remounted Oziella virgata n. sp. A (DIC LM) & B (PCLM) — prodorsal shield; C — whole mites (pseudo dark field PC LM), D — empodium I and arrowed u' I (PC LM), E — coxigenital area (DIC LM). Scale bar: A, B = 15 µm; C = 100 µm; D = 4 µm; E = 20 µm. Note: in D, the empodium is slightly curved and appears to have fewer rays (9 / 5) than it actually has (10 / 9).