Novophytoptus luzulis Chetverikov, 2015, n. sp.

• Main Author: Chetverikov, Philipp E.
• Format: Text
• Language: unknown
• Published: Zenodo 2015
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Arachnida; Prostigmata; Phytoptidae; Novophytoptus; Novophytoptus luzulis; Awl; Plesetsk; Seta; Arkhangelsk; Mite; Siberia
• Online Access: https://dx.doi.org/10.5281/zenodo.6103077; https://zenodo.org/record/6103077

Novophytoptus luzulis n. sp. (Figs. 1 D–I, 2 D–F, 3 D–F, 4, 5 A–I, 6 A–C, 7 E–F, 8) Female (n= 9: holotype & paratypes). Idiosoma vermiform, 341 (270–356), 54 (42–54) wide at the level of setae c2 , 68 (45–68) wide at the level of setae f . Prodorsal shield (Fig. 1 D–I) subpentagonal, 33 (27–34) x 25 (24–28) wide with two ocella-like spots lateral to setae ve . Anterior margin of prodorsal shield forming a triangular extremity resting on enlarged fused basal parts of chelicerae and associated with basal gnathosomal structures of unknown origin (Fig. 4, coloured pink). Shield ornamentation with several median longitudinal ridges, tightly packed, forming a very narrow figure of 8 or bottle-shape with a “neck” centrally (better seen in Fig. 1 H,I). Anteriorly, this “bottle” includes five thin ridges, whereas posteriorly, only three (rarely four) are observed (see Fig. 1 H). The ridges converge anteriorly and posteriorly. Two to three thin lines present between tubercles ve and anterior part of “bottle”. Rudimentary posteromedian fovea (“pit” sensu Keifer) surrounded by small scattered lines on rear prodorsal shield margin; 57 (52–80) circular/oval granules between sc tubercles. Setae ve 16 (11–19), directed anterolaterad, tubercles 15 (12–15) apart; sc 109 (74–116) long, directed posterolaterad, tubercles 15 (12– 15) apart. Distance between tubercles ve–sc 20 (16–22). Gnathosoma elongate, directed forward and slightly ventrad, 23 (21–25); pedipalp coxal seta ep 6 (3–6), pedipalp genual seta d absent (Fig. 4), subapical pedipalp tarsal seta ν 0.5 (0.5–1). Ventrally, basal gnathosoma covered by petal-like suboral plate bearing two cuticular ridges, forming V-shaped figure (Fig. 3 E). Leg I 38 (32–39), tibia 10 (7–12), l ′ 6 (4–8), tarsus 7 (4–7), u ′ 1 (1–1.5), ft ′ 4 (2–4), ft″ 22 (17–25), ω 5 (4–6); empodium I 4 / 4 -rayed, 6 (6–8), each ray of the three basal pairs with one additional secondary branch, terminal paired rays without additional branching and usually of equal length (one of the terminal rays of left empodium I was half as long as the other in one specimen; Fig. 2 D). Leg II 9 (6–9), tibia 9 (6–9), tarsus 7 (5–7), u ′ 1 (1–1.5), ft ′ 4 (2–4), ft″ 22 (17–25), ω 8 (7–9); empodium II 4 / 4 -rayed, 6 (6–8), each ray of the three basal pairs with one additional secondary branch, terminal paired rays without additional branching, internal terminal ray 2–3 times longer than external (thus empodia II are asymmetrical). Tiny denticles present both ventrally and dorsally on anterior margin of trochanter, femur, genu and tibia in legs I and II. Femora I and II with 2–3 ventral longitudinal striae. Coxae each ornamented with 4–5 longitudinal lines. Prosternal apodeme inversely T-shaped, caudally with three short internal processes forming together a tridentate fork (Fig. 3 D–F). Setae 1 b 11 (11–15), 12 (11–15) apart; 1a 17 (14–19), 20 (19–23) apart; 2a 53 (44–54), 20 (19–23) apart; 15 (10–15) coxigenital annuli before epigynium (posterior annuli complete, anterior 2–3 incomplete, i.e. segregated from lateral annuli). Genital coverflap (Fig. 4 G) semi-circular, smooth, 10 (9–11) x 16 (14–16) wide; setae 3a 13 (11–15), 17 (14–18) apart (Fig. 6 A–C). Opisthosoma vermiform, slightly expanded caudally, widest at level of tubercles f dorsal and ventral annuli bearing small, oval microtubercles, except last 5–6 dorsal annuli devoid of microtubercles. Setal lengths: c 2 40 (34–47), d 26 (23–29), e 16 (13–18), f 17 (16–18), h 1 11 (8–11), awl-like (Fig. 7 E–G); h 2 broken in type female, (70–105) in paratypes. Setae c2 , 3a , d and f , notably thickened. 10 (8–12) annuli from rear shield margin to c 2 14 (12–15) annuli between c 2 –d 17 (14–18) annuli between d and e 25 (20–26) annuli between e and f 6 (5–6) annuli between f and h 1 . Remarks . One aberrant female of N. luzulis n. sp. had a constriction in the central part of the body and an irregular pattern of opisthosomal annuli (slide #u 1 / 3-12) (Fig. 8). This constriction could be considered the result of an unsuccessful nymphal molt, mutation or even perhaps a predator bite-mark. The fact that this female also had deformed tarsi I with shortened, displaced tarsal appendages (not figured here) supports the first two hypotheses. Male (n= 5). Males are shorter than females and have shorter setae sc . They have similarly shaped empodia I and II with terminal rays the same length as basal rays (Table 1, Fig. 5 I) Host plant . Luzula pilosa (L.) Willd (hairy wood-rush), distributed in Europe and Siberia. Relation to the host . Mites live under the leaf epidermis in spaces of mesophyll where they feed on parenchymatous cells. Such feeding putatively causes necrosis of tissues, resulting in a light brown colour of the infested leaf area (Fig. 9). Type locality . RUSSIA: Arkhangelsk Prov., Plesetsk, 62 ° 43 ′ 51 ″N, 40 ° 17 ′ 5 ″E. Type material . Female holotype on slide # 24 - 13. In addition, 17 paratype females, six males and ten immatures (each on a separate slide). All specimens from RUSSIA: Arkhangelsk Prov., Plesetsk, 62 ° 43 ′ 51 ″N, 40 ° 17 ′ 5 ″E, 20 August 2012, coll. P.E. Chetverikov. Additional material . 18 mite specimens on five slide mounts collected 20 August 2004 (same host, locality and collector as type material); 22 mites on 13 slides collected from RUSSIA: Leningrad Prov., Gatchina district, village Belogorka, right bank of river Oredezh, 59 ° 20 ′ 32 ″N, 30 ° 10 ′ 29 ″E, 4 May 2013 and 16 August 2013 (same host and collector). Etymology . The specific epithet, luzulis , is an adjective, gender masculine, corresponding to the generic name of the host plant. Differential diagnosis . Mites of N. luzulis n. sp. are morphologically very similar to N. aculeatus Pye, 2012. These two species have almost identical prodorsal shield ornamentation but differ in the number of dorsal opisthosomal annuli, the shape of h 1 and empodia I and II, and lengths of opisthosomal setae c 2 , d , e , f , which are approximately twice as long in N. luzulis n. sp. as in N. aculeatus (Table 3). Additionally, these two species inhabit plants from different juncaceous genera ( Luzula and Juncus , repectively), and their hosts have overlapping distributions: Luzula pilosa is distributed in Europe and Siberia whereas Juncus squarrosus L. (mosquito rush) is native to Europe and Morocco as well as being introduced in the USA (Wisconsin) and Denmark (Govaerts 2014; USDA NRCS 2014). Characters Mite species : Published as part of Chetverikov, Philipp E., 2015, Hidden diversity of endoparasitic eriophyoid mites: two new Novophytoptus Roivainen, 1947 (Acari: Eriophyoidea: Phytoptidae) species from the parenchymatous tissues of rushes (Juncaceae), pp. 481-505 in Zootaxa 4006 (3) on pages 488-494, DOI: 10.11646/zootaxa.4006.3.4, http://zenodo.org/record/239377 : {"references": ["Pye, D. R. (2012) New eriophyoid mites (Acari: Prostigmata: Eriophyoidea) in Britain: one new genus, four new species, 19 new records and two incursions. Zootaxa, 3578, 43 - 68.", "Govaerts, R. (compiler) (2014) World Checklist of Juncaceae. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http: // apps. kew. org / wcsp / (accessed 30 April 2014)", "USDA, NRCS (2014) The PLANTS Database National Plant Data Team, Greensboro, NC 27401 - 4901 USA. Available from: http: // plants. usda. gov (accessed 31 March 2014)"]}