Trouessartia pyrrhulae, Mironov & Dmitryukov, 2025

Mironov, Sergey V. & Dmitryukov, Arsenii V., 2025, Three new species of the feather mite genus Trouessartia (Acariformes: Trouessartiidae) from passerines (Passeriformes) in the Asian part of Russia, Zootaxa 5661 (2), pp. 178-200 : 190-197

Trouessartia pyrrhulae sp. nov.

Zoobank: 9280D3AC-C7C3-44C8-977B-4538C1673650

( Figs 9–12 , 14C, D )

Type material. Holotype male ( ZISP 23732 ) , 8 male and 7 female paratypes ( ZISP 23733–23747 ) from Pyrrhula pyrrhula Linnaeus, 1758 ( Passeriformes : Fringillidae ), SVM-12-0823-4(3), Russia, Primorsky Krai, Krasnoarmeiski District, Iman river , 25 km S of Melnichnoye , 44°59’43.7”N, 134°04’13.7”E, 23 August 2012, coll. S.V. Mironov.

Description. MALE (holotype, ranges for 8 paratypes in parentheses) ( Figs 9 , 11A , 12A–D, F ). Idiosoma, length × width, 590 (585–610) × 320 (315–325), length of hysterosoma 400 (400–420). Prodorsal shield: length along midline 165 (165–175), greatest width posterior to scapular setae 200 (195–210), anterior part at level of trochanters II not narrowed, anterolateral extensions angular with widely rounded ends, not extending to rudimentary epimerites Ia between legs I and II, lateral margins not fused with scapular shields, posterior margin straight, surface without ornamentation. Internal scapular setae si narrowly lanceolate, 50 (50–62) long, separated by 61 (61–66); external scapular setae se separated by 120 (120–130). Setae c2 thick spiculiform, 90 (87–90) long, situated in anteromedian angles of humeral shields. Setae c3 lanceolate with pointed apex, 27 (27–28) long ( Fig. 12F ). Prohysteronotal and lobar parts of the hysteronotal shield connected, delimited from each other by lateral incisions extending to bases of setae e2, total length of hysteronotal shield from anterior margin to lobar apices excluding terminal lamellae 380 (375–395), width at anterior margin 210 (210–220). Lateral margins at level of trochanters III straight and heavily sclerotized, but these dark areas do not form separate patches and fused with large sclerotized bands along lateral borders of prohysteronotal shield, surface without ornamentation. Dorsal setae d1, d2, e2 present, setae f2 absent. Opisthosoma strongly attenuate posteriorly; opisthosomal lobes fused with each other along midline forming a heavily sclerotized median septum, apical parts of lobes posterior to level of setae h2 separated by narrow parallel-sided terminal cleft. Length of terminal cleft from anterior end to lobar apices 41 (35–41); length from anterior end to posterior margins of terminal lamellae 70 (70–73), width of cleft 5 (5–7). Terminal lamellae semi-ovate, with smooth margin, length from bases of setae h3 to lamellar apices 30 (30–38), greatest width 35 (35–37). Distances between dorsal setae: c2:d2 90 (90–93), d2:e2 123 (121–132), e2:h2 106 (106–113), h2:h3 38 (35–38), h2:h2 53 (53–57), h3:h3 41 (41–48), e1: e2 60 (55–60), ps1:h3 12 (9–12).

Epimerites I free. Rudimentary sclerites rEpIIa small ovate. Genital apparatus: long and narrow, strongly convex dorsally, length excluding epiandrum 64 (64–68), greatest width 15 (14–15); epiandrum ovate; distal ends of parameres without denticles; aedeagus shaped as narrow cone approximately half as long as parameres; latigenital sclerites absent, basal sclerite barely extending to level of setae g ( Fig. 11A ). Anterior and posterior pairs of genital papillae similar in size, anterior papillae more distant from midline. Genital shield represented by small irregular sclerites at bases of setae g. Setae g filiform, about 1/3 or more the distance between setae g and ps3, with bases not adjacent to each other. Postgenital plaque small trapezoidal. Apophyses of adanal apodemes represented by small tubercles situated behind level of adanal suckers. Lateral margins of opisthosoma at level of adanal sucker strongly convex. Translobar apodeme wide. Adanal shields represented by small ovate sclerites bearing setae ps3. Adanal suckers 14 (13–14) in diameter. Anterior ends of epimerites IIIa extending to level of setae 4b, their inner margins with blunt-angular extension or without it. Epimerites IVa shaped as roughly ovate plates, with anterior ends not extending to level of setae g. Setae 4b situated anterior to level of setae 3a, both pairs anterior to genital apparatus apex; setae g and 4a approximately at same transverse level. Distances between ventral setae: 4b:3a 12 (6–12), 4b:4a 102 (97–102), 4a:g 2(2–6), g:ps3 83 (82–93), ps3:h3 140 (135–140).

Legs. Setae cG, mG of genua I, II filiform. Genual solenidia σ I and σ II situated at midlength of corresponding genua ( Fig. 12A, B ). Trochanteral setae sR III narrowly lanceolate, with pointed apex, 23 (22–23) long. Legs IV with ambulacral disc extending to level of setae h3. Tarsus IV 50 (49–50) long; modified setae d barrel-shaped with discoid cap, situated in distal one third of this segment; modified setae e cylindrical, without cap, situated apically ( Fig. 12D ). Lengths of solenidia: σ I 76 (63–76), σ II 25 (20–25), σ III 45 (44–49), φ IV 63 (60–64).

FEMALE (range for 7 paratypes) ( Figs 10 , 11B, C , 12E , 14C, D ). Idiosoma, length × width, 663–705 × 325– 346, length of hysterosoma 472–490. Prodorsal shield: shape as in male, surface with faint reticulate ornamentation, 170–190 × 210–220. Setae si spiculiform, 52–63 long, separated by 68–77; setae se separated by 132–139. Setae c2 narrowly lanceolate, with pointed apex, 83–91 long, situated in anteromedial angle of humeral shields. Setae c3 lanceolate, with pointed apex, 29–32 long. Hysteronotal shield: length from anterior margin to posterior tips 415–445, width at anterior margin 230–250; lateral margins at level of trochanters III almost straight, longitudinal sclerotized patch at these margins only slightly darker than large sclerotized bands going along entire border of this shield; surface of posterior half from level of setae d2 with numerous large circular and ovate lacunae, lacunae along midline noticeably smaller ( Figs 10A , 11B ). Dorsal setae d1, d2, e2 present. Setae h1 narrowly lanceolate, 40–44 long, situated anteromesal to setae h2, 23–25 from corresponding lateral margins of hysteronotal shield. Width of opisthosoma at level of setae h2 140–150. Setae ps1 equidistant from margins of opisthosomal lobes. Supranal concavity open posteriorly into terminal cleft. Length of terminal cleft from anterior end of supranal concavity to lobar apices 150–170, length from free margin of interlobar membrane to lobar apices 94–98, greatest width of cleft 65–70. Interlobar membrane occupying about 1/2 of terminal cleft. External copulatory tube long stylet-like, situated on free margin of interlobar membrane, 42–45 long; basal guides of copulatory tube longer than tube and fused into gutter-like sclerite covering primary spermaduct dorsally; primary spermaduct guide short. Distances between dorsal setae: c2:d2 99–107, d2:e2 126–135, e2:h2 80–87, h2:h3 59–63, h2:h2 109–117, h3:h3 91–100, d1: d2 50–58, e1:e2 69–73, h1:h2 12–15, h1:h1 66–72, ps1:h3 17–18.

Epimerites I free. Epigynum 47–53 long, 110–122 wide. Inner margins of epimerites IIIa with short pointed or bluntly angular extension. Epimerites IVa present. Adanal sclerites small ovate. Setae f2 and ps2 present. Head of spermatheca with collar bearing 6-8 long acute denticles; primary spermaduct slightly enlarged near head of spermatheca; secondary spermaducts 30–35 long ( Fig. 11C ).

Legs. Setae cG, mG of genua I, II filiform. Trochanteral setae sR III narrowly lanceolate, with pointed apex, 23–26 long. Legs IV with ambulacral disc extending to level of setae ps1. Length of solenidia: σ I 62–69, σ II 23–25, σ III 32–50.

Barcoding data. The Genbank accession number of the COI sequence is PV370491.

Etymology. The specific epithet is taken from the species name of the type host and is a noun in apposition.

Differential diagnosis. Trouessartia pyrrhulae sp. nov. is most close to T. jedliczkai (Zimmermann, 1894) and T. motacillae Dubinin, 1952 inhabiting M. flava Linnaeus and Motacilla alba Linnaeus ( Motacillidae ), respectively. These species share the following features in females: the external copulatory tube is long stylet-like, and the collar of spermatheca has a comb of acute denticles. Trouessartia pyrrhulae differs from both aforementioned species in having the following features: in both sexes, sclerotized patches at the lateral margins of hysteronotal shield are narrow and poorly distinct, setae c2 are similar in length to the humeral shields; in males, the prohysteronotal and lobar parts of the hysteronotal shield are connected and demarcated from each other by lateral incisions at level of setae e2, the length of setae g is about 1/3 the distance between setae g and ps3; in females, the tip of the external copulatory tube extends beyond the level of setae h3, and all lacunae in the posterior half of hysteronotal shield are uniformly outlined. In both sexes of T. jedliczkai and T. motacillae , the lateral margins of the hysteronotal shield have a pair of distinct bean-shaped sclerotized patches at the level of trochanters III, setae c2 are half as long as the humeral shields; in males, the prohysteronotal and lobar parts of the hysteronotal shield are completely separated (in T. motacillae ) or are connected by a narrow median bridge ( T. jedliczkai ), the length of setae g is about 1/2 the distance between setae g and ps3; in females, the tip of external copulatory tube does not extend to the level of setae h3, and small lacunae arranged along the midline are outlined much more clearly than the remaining larger lacunae on the posterior part of the hysteronotal shield.

Remark. It can look strange that Trouessartia pyrrhulae , described above from the Eurasian bullfinch Pyrrhula pyrrhula in the Russian Far East, was not detected on this host in Europe, where this bird is common although not abundant, and feather mite investigations have been conducted for over 150 years. This can be explained by the following hypothesis. The Eurasian bullfinch is the only species of eight species of the genus Pyrrhula Brisson having a giant geographical range across the entire Eurasia, from the Western Europe to Kamchatka peninsula ( Gill et al. 2024). All remaining species of the genus Pyrrhula , except P. murina Godman , are distributed in the oriental part of Asia: from Himalayan considered the center of origin and dispersion of this genus to South-East Asia. Undescribed Trouessartia species were reported from bullfinches in South-East Asia, in particular from P. nipalensis Hodgson ( Atyeo 1973) . It is reasonable to conclude that P. pyrrhula has lost T. pyrrhulae during dispersion from Asia to the Western Europe and retained this mite species only in the ancestral part of range. On the Azores Bullfinch P. murina , which is the closest to P. pyrrhula , any Trouessartia species was also not detected, although this Azorean endemic bears two other feather mites, Analges macropus Zimmermann, 1894 ( Analgidae ) and Mesalgoides pyrrhulinus Mironov, 1997 ( Psoroptoididae ), which are common for the Eurasian bullfinch ( Rodrigues et al. 2015).

Figures

FIGURE 9. Trouessartia pyrrhulae sp. nov., male. A—dorsal view, B—ventral view.

FIGURE 10. Trouessartia pyrrhulae sp. nov., female. A—dorsal view, B—ventral view.

FIGURE 11. Trouessartia pyrrhulae sp. nov., details. A—genital apparatus and opisthosoma of male, ventral view, B— opisthosoma of female, dorsal view, C—spermatheca. Abbreviations: ad—adanal apodeme, ae—aedeagus, ap—apophysis of adanal apodeme, bs—basal sclerite, cl—collar of spermatheca head, ea—epiandrum, gs—genital shield, gt—basal guide of copulatory tube, hs—head of spermatheca, is—intermedial sclerite, sd—secondary spermaduct, pd—primary spermaduct, pg— primary spermaduct guide, pm—paramere, pp—postgenital plaque, tl—terminal lamella.

FIGURE 12. Trouessartia pyrrhulae sp. nov., details.A, B—legs I, II of male, C, D—tibiae and tarsi III, IV of male, E— tibia and tarsus IV of female, F—setae si, c2, c3 and sRIII of male.

FIGURE 14. Trouessartia females, dorsal shields.A— Trouessartia mugimaki sp. nov., prodorsal shield, B—same, hysteronotal shield, C— T. pyrrhulae sp. nov., prodorsal shield, D—same, hysteronotal shield.