Trouessartia passerinae Mironov and Chandler, 2020

Mironov, Sergey V. & Chandler, C. Ray, 2020, Feather mites of the genus Trouessartia (Acariformes: Trouessartiidae) from passerines (Aves: Passeriformes) in Georgia, USA, Zootaxa 4860 (1), pp. 1-54 : 6-11

Trouessartia passerinae Mironov and Chandler , sp. n.

( Figs. 1–3 , 4 A–C)

Type material. Holotype male ( BMOC 20-0303-009), 10 male and 12 female paratypes from Passerina caerulea (Linnaeus, 1758) ( Passeriformes : Cardinalidae ), ( SVM 18-0530-11/3), USA, Georgia, Telfair Co., 21 May 2017, coll. C. R. Chandler.

Depositories. Holotype, 5 male and 6 female paratypes—UMMZ, remaining paratypes—ZISP.

Additional material. 3 males and 3 females from Passerina cyanea (Linnaeus, 1766) ( Passeriformes : Cardinalidae ), ( SVM 18-0530-15), USA, Georgia, Statesboro, Georgia Southern University Campus, 32°25’15”N, 81°47’22”W, 22 April 2015, coll. C. R. Chandler.

Description. MALE (holotype, ranges for 10 paratypes in parentheses) ( Figs. 1 , 3 A–C, 4A). Idiosoma, length × width, 445 (420–470) × 210 (200–225), length of hysterosoma 285 (270–300). Prodorsal shield: length along midline 140 (135–145), greatest width posterior to level of scapular setae 160 (150–165), anterior part at level of trochanters II not narrowed, anterolateral extensions rounded, not extending to bases of epimerites Ia between legs I and II, lateral margins not fused with scapular shields, posterior margin straight, surface without ornamentation. Internal scapular setae si spiculiform with filiform apex, 35 (30–35) long, separated by 60 (57–63); external scapular setae se separated by 100 (100–110). Setae c2 with filiform apex, 53 (50–55) long, situated in anteromedian angle of humeral shields. Setae c3 narrowly lanceolate, with bidentate apex (with apical and subapical denticles), 25 (18–25) long ( Fig. 3E ). Hysteronotal shield completely separated into prohysteronotal and lobar parts, total length from anterior margin to lobar apices excluding lamellae 275 (265–290). Prohysteronotal shield: length along midline 185 (180–195), width at anterior margin 155 (145–165), lateral margins at level of trochanters III with shallow concavities flanked by bean-shaped sclerotized patches, dorsal hysterosomal apertures (DHA) absent, surface without ornamentation. Dorsal setae d1, d2, e2 present. Setae f2 absent. Length of lobar shield 90 (85–95). Opisthosoma strongly attenuate posteriorly; opisthosomal lobes fused with each other along midline forming a heavily sclerotized median septum, only 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 28 (25–28); length from anterior end to posterior margin of terminal lamellae 50 (50–55), width 5 (5–6). Terminal lamellae semi-ovate, widely rounded posteriorly, with smooth margins, length from bases of setae h3 to lamellar apices 28 (28–30), greatest width 25 (25–30). Distance between dorsal setae: c2:d2 70 (70–75), d2:e2 95 (90–98), e2:h2 75 (70–78), h2:h3 22 (20–22), h2:h2 40 (40–43), h3:h3 28 (28–30), d1:d2 43 (42–50), e1: e2 42 (40–45), ps1:h3 8 (7–8).

Epimerites I free. Rudimentary sclerites rEpIIa small ovate. Genital apparatus: length excluding basal sclerite 45 (45–48), greatest width 25 (20–25), aedeagus short cone-shaped, epiandrum (pregenital sclerite) roughly ovate, latigenital sclerites absent, distal ends of parameres without denticles ( Fig. 4A ). Anterior genital papillae slightly larger and more distant from midline than posterior ones. Postgenital plaque large semicircular. Setae g filiform (not enlarged basally), approximately half as long as distance between setae g and ps3, their bases well separated from each other and situated on crescent-shaped genital shield. Apophyses of adanal apodemes ridge-shaped, anterior end with roughly rectangular or rounded tubercle. Lateral margins of opisthosoma with narrow membranes at level of adanal suckers. Translobar apodeme present. Adanal shields represented by small triangular sclerites around bases of setae ps3. Adanal suckers 13 (13–15) in diameter. Inner ends of epimerites IIIa extending to level of setae 4b, without noticeable extensions on inner margins. Epimerites IVa as plates of irregular form, with anterior ends extending to level of setae g. Setae 4b situated anterior to level of setae 3a; setae g posterior to level of setae 4a. Distance between ventral setae: 4b:3a 10 (8–10), 4b:g 90 (82–98), 4a:g 12 (12–15), g:ps3 35 (32–38), ps3: h3 100 (95–105), g:g 10 (10–15).

Setae cG, mG of genua I, II filiform. Genual solenidia σ I and σ II situated at midlength of corresponding genua ( Fig. 3A, B ). Trochanteral setae sR III narrowly lanceolate, with acute apex, 15 (15–17) long. Legs IV with ambulacral disc extending to level of setae h3. Tarsus IV 33 (30–33) long; modified setae d barrel-shaped, with discoid cap, situated in distal one third of this segment; modified setae e button-like, without cap, situated apically ( Fig. 3D ). Length of solenidia: σ I 55 (50–56), σ II 12 (10–14), σ III 25 (22–23), φ IV 38 (33–38).

FEMALE (range for 10 paratypes) ( Figs. 2 , 3F, G , 4B, C ). Idiosoma, length × width, 495–540 × 210–240, length of hysterosoma 335–340. Prodorsal shield: shaped as in male, 140–155 long, 150–175 wide, surface without ornamentation. Setae si filiform, 30–33 long, separated by 60–65; setae se separated by 100–110. Setae c2 with filiform apex, 48–53 long, situated in anteromedial angle of humeral shields. Setae c3 narrowly lanceolate, with acute apex, 21–23 long. Hysteronotal shield: length from anterior margin to posterior tips 305–345, width at ante- rior margin 150–170, lateral margins at level of trochanters III with shallow concavities flanked by bean-shaped sclerotized patches, dorsal hysterosomal aperture (DHA) absent, median area from level of setae c3 to trochanters IV with poorly distinct small ovate lacunae, posterior part between levels of setae e1 and supranal concavity with small longitudinal dash-like lacunae. Dorsal setae d1, d2, e2 present. Setae h1 narrowly lanceolate, 24–26 long, situated of setae h2, 20–23 from corresponding lateral margins of hysteronotal shield. Width of opisthosoma at level of setae h2 90–105. Setae ps1 situated dorsally, 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 135–145, length from free margin of interlobar membrane to apices 96–105, greatest width of cleft 38–45. Interlobar membrane occupying anterior 1/8th of terminal cleft. External copulatory tube short conical, situated on free margin of interlobar membrane, 9–13 long; basal guides of copulatory tube and primary spermaduct guide well developed. Distance between dorsal setae: c2:d2 75–85, d2:e2 88–98, e2:h2 58–63, h2:h3 58–65, h2:h2 75–87, h3: h3 47–63, d1:d2 43–48, e1: e2 35–43, h1:h2 15–18, h1:h1 45–50, ps1:h3 15–16.

Epimerites I free. Epigynum 42–43 long, 92–102 wide. Inner margins of epimerites IIIa with blunt-angular extension. Epimerites IVa present. Adanal sclerites barely distinct or absent. Setae f2, ps2 present. Head of spermatheca with smooth semi-ovate peak, primary spermaduct without enlargement, secondary spermaducts 28–30 long ( Fig. 4B ).

Legs I, II as in males ( Fig. 3A, B ). Trochanteral setae sR III narrowly lanceolate, acute apically, 15–18 long. Legs IV with ambulacral disc extending to setae ps1. Length of solenidia: σ I 50–55, σ II 12–13, σ III 22–25.

Differential diagnosis. Among previously described species referred to the capensis species group, Trouessartia passerinae sp. n. is most similar to T. capensis Berla, 1959 in having a wide semicircular postgenital plaque and bases of setae g distant from each other in males. Trouessartia passerinae sp. n. readily differs from T. capensis by the following features: in both sexes, the lateral margins of the hysteronotal shield at the level of trochanters III are shallowly concave and flanked by slightly curved sclerotized patches; in males, setae g are filiform, and the genital shield is crescent-shaped; in females, the external copulatory tube is short and conical (9–13), setae h1 are 24–26 long and barely extend to the anterior margin of the interlobar membrane, and the posterior 1/3 of the hysteronotal shield bears numerous longitudinal dash-shaped lacunae. In both sexes of T. capensis , the lateral margins of the hysteronotal shield at the level of trochanters III have small and deep incisions flanked by a C-shaped sclerotized patch; in males, setae g are widened and flattened in their basal two thirds, and the genital shield is trapezoidal in shape; and in females, the external copulatory tube is 34–38 long, setae h1 are 46–56 long and distinctly extend beyond the free margin of the interlobar membrane, and the posterior 1/3rd of the hysteronotal shield bears oblique ovate lacunae.

Etymology. The specific epithet is taken from the generic name of the type host and is a noun in the genitive case.

Figures

FIGURE 1. Trouessartia passerinae sp. n., male. A—dorsal view, B—ventral view.

FIGURE 2. Trouessartia passerinae sp. n., female. A—dorsal view, B—ventral view.

FIGURE 3. Trouessartia passerinae sp. n., details. A–C—legs I–III of male, respectively, D—tibia and tarsus IV of male, E—setae si, c2, c3 and sRIII of male, F, G— tibia and tarsus IV of female, respectively.

FIGURE 4. Trouessartia species, details. A—Trouessartia passerinae sp. n., opisthosoma and genital apparatus of male, ventral view, B—same, spermatheca and spermaducts, C—same, opisthosoma of female, dorsal view, D—T. capensis Berla, 1959, opisthosoma of female, dorsal view, D—T. geospiza OConnor et al. 2005, opisthosoma of female, dorsal view. Abbreviations: ae—aedeagus, ad—adanal shield, ap—apophysis of adanal apodeme, bs—basal sclerite, ea—epiandrum, bg—basal guide of external copulatory tube, gs—genital shield, hs—head of spermatheca, eh—peak-like extension of spermathecal head, pg—primary spermaduct guide, pp—postgenital plaque, pd—primary spermaduct, pm—paramere, sd—secondary spermaducts, tatranslobar apodeme, tl—terminal lamella.