Trouessartia pensylvanica 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 : 44-48

Trouessartia pensylvanica Mironov and Chandler , sp. n.

( Figs. 29–31 )

Type material. Holotype male ( BMOC 20-0303-012), 1 male and 2 female paratypes from Setophaga pensylvanica (Linnaeus, 1766) ( Passeriformes : Parulidae ), ( SVM 15-1013-8), USA, Georgia, Statesboro, Georgia Southern University campus, 16 October 2013, coll. J. Lowery.

Additional material. 3 males, 4 females from Setophaga pensylvanica, (SVM 1326) , Canada, Manitoba, Winnipeg, 1 June 2004, T.D. Galloway; 5 males, 5 females from S. palmarum (Gmelin, JF, 1789) ( Passeriformes : Parulidae ), ( SVM 2559), Canada, Manitoba, Selkirk, 14 May 2013, T.D. Galloway and C. R. Wushke.

Depositories. Holotype and 1 female paratypes— UMMZ, remaining paratypes—ZISP.

Description. MALE (holotype, measurements for 1 paratype in parentheses) ( Figs. 29 , 31 A–D, G). Idiosoma, length × width, 455 (440) × 205 (195), length of hysterosoma 310 (295). Prodorsal shield: length along midline 140 (135), greatest width posterior to level of scapular setae 160 (155), anterior part at level of trochanters II not narrowed, anterolateral extensions angular, extending to but not fused with bases of epimerites Ia, lateral margins not fused with scapular shields, posterior margin almost straight, surface without ornamentation. Internal scapular setae si thin spiculiform, 32 (28) long, separated by 58 (55); external scapular setae se separated by 105 (100). Setae c2 spiculiform, 48 (40) long, situated in anteromedian angle of humeral shields. Setae c3 narrowly lanceolate, with bidentate apex, 25 (23) long. Hysteronotal shield completely separated into prohysteronotal and lobar parts, total length 305 (295). Prohysteronotal shield: length along midline 200 (195), width at anterior margin 160 (155), lateral margins at level of trochanters III with incision flanked by C-shaped heavily sclerotized patch, DHA absent, surface without ornamentation. Dorsal setae d2, e2 present. Setae d1, f2 absent. Length of lobar shield excluding terminal lamellae 105 (100). 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 cleft from anterior end to lobar apices 25 (23); length from anterior end to apices of terminal lamellae 50 (48), width 6 (8). Terminal lamellae semi-ovate, with smooth margins, length from bases of setae h3 to lamellar apices 32 (35), greatest width 28 (26). Distance between dorsal setae: c2:d2 75 (70), d2:e2 110 (105), e2:h2 85 (80), h2:h3 23 (25), h2:h2 42 (40), h3:h3 33 (35), e1: e2 52 (46), ps1:h3 11 (8).

Epimerites I free. Lateral half of coxal fields II heavily sclerotized. Rudimentary sclerites rEpIIa large ovate, 10–12 in diameter, with a small lacuna. Genital apparatus: length excluding basal sclerite 56 (57), greatest width 28 (30), epiandrum ovate, latigenital sclerites absent, distal ends of parameres without denticles, aedeagus shaped as thick conoid (fustum). Anterior and posterior genital papillae subequal in size, anterior papillae more distant from midline than posterior ones. Postgenital plaque small trapezoidal, with small concavity on posterior margin. Setae g long, noticeably thickened in basal part, with bases separated, sclerotized areas around them fused into a small inverted Y. Apophyses of adanal apodemes represented by narrow membranous ridges with convex lateral margin. Lateral margins of opisthosoma with barely distinct lateral membranes. Translobar apodeme present. Adanal shields represented by small triangular sclerites around bases of setae ps3. Adanal suckers 14 (13) in diameter. Inner ends of epimerites IIIa with apices extending distinctly beyond level of setae 4b, and without extensions on inner margins. Epimerites IVa wide, with anterior ends extending to level of setae g. Setae 4b situated anterior to level of setae 3a; setae g slightly posterior to level of setae 4a. Distance between ventral setae: 4b:3a 10 (12); 4b:g 87 (88), g:ps3 57 (58), ps3:h3 107 (102); g:g 7 (8).

Setae cG, mG of genua I, II filiform. Genual solenidia σ I and σ II situated at midlength of corresponding genu ( Fig. 31A, B ). Trochanteral setae sR III narrowly lanceolate, with bidentate or truncate apex, 18 (17) long. Legs IV with ambulacral disc extending to level of setae h3. Tarsus IV 38 (37) 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. 31C ). Length of solenidia: σ I 52 (50), σ II 17 (13), σ III 26 (25), φ IV 40 (38).

FEMALE (range for 2 paratypes) ( Figs. 30 , 31E, F ). Idiosoma, length × width, 500–510 × 195–200, length of hysterosoma 360–365. Prodorsal shield: shaped as in male, 140–145 long, 159–155 wide, surface without ornamentation. Setae si thin spiculiform, 25–30 long, separated by 53–55; setae se separated by 100–105. Setae c2 spiculiform, 40–45 long, situated in anteromedial angle of humeral shields. Setae c3 narrowly lanceolate, with bidentate apex, 23–24 long. Hysteronotal shield: length from anterior margin 345–350, width at anterior margin 145–150, lateral margins at level of trochanters III with incision flanked by C-shaped sclerotized patch, DHA absent, anterior half with small circular lacunae, posterior part between level of setae e1 and supranal concavity with longitudinally ovate lacunae. Dorsal setae d2, e2 present. Setae d1 absent. Setae h1 narrowly lanceolate, 24–30 long, situated antero-mesal to bases of setae h2, 22–25 from corresponding lateral margins of hysteronotal shield, not extending to free margin of interlobar membrane. Width of opisthosoma at level of setae h2 95–105. Setae ps1 situated dorsally, equidistant from inner and outer margins of opisthosomal lobes. Supranal concavity open posteriorly into terminal cleft. Length of terminal cleft from anterior end of supranal concavity to lobar apices 145–150, length from free margin of interlobar membrane to apices 100–105, width of cleft at level of setae h3 35–40. Interlobar membrane occupying anterior 1/6th of terminal cleft. External copulatory tube straight finger-like with rounded apex, situated on free margin of interlobar membrane, 30–32 long; basal guides of copulatory tube and primary spermaduct guide in supranal concavity well developed. Distance between dorsal setae: c2:d2 72–78, d2:e2 100–105, e2:h2 58–63, h2:h3 72–73, h2:h2 72–78, h3:h3 50–55, e1: e2 35–50, h1:h2 15–18, h1:h1 37–40, ps1:h3 18–20.

Epimerites I free. Epigynum 40–45 long, 92–98 wide. Inner margins of epimerites IIIa with denticle-like extension. Epimerites IVa large.Adanal sclerites rudimentary. Setae f2, ps2 present. Head of spermatheca with semi-ovate extension, primary spermaduct without enlargement, secondary spermaducts 25–28 long ( Fig. 31E ).

Legs I, II as in males. Trochanteral setae sR III narrowly lanceolate, with bidentate or truncate apex, 17–18 long. Legs IV with ambulacral disc extending to midlength between setae h2 and h3. Length of solenidia: σ I 44–45, σ II 14–15, σ III 23–25.

Differential diagnosis. Among species of the capensis group lacking dorsal setae d1, Trouessartia pensylvanica sp. n. is most similar to T. mniotilta described above in having, in males, setae g long and noticeably enlarged basally and the genital shield shaped as a small inverted Y, and, in females, the external copulatory tube fingershaped and setae h1 not extending to the margin of the interlobar membrane. The new species is distinguished from T. mniotilta by the following features: in both sexes of T. pensylvanica , the lateral halves of coxal fields II are heavily sclerotized; in males, epimerites IVa extend to the level of setae g, the apophyses of the adanal apodemes are narrow membranes with a slightly convex free margin; in females, the hysteronotal shield is longer (345–350). In both sexes of T. mniotilta , only the narrow lateral area of coxal fields II is heavily sclerotized; in males, epimerites IVa do not extend to the level of setae g, the apophyses of the adanal apodemes are shaped as a ridge with rounded tubercle at the anterior end; in females, the hysteronotal shield is shorter (320–335). The extensively sclerotized lateral parts of coxal fields II in T. pensylvanica readily differentiate this species from all other species of the capensis group lacking setae d1.

Etymology. The specific epithet is taken from the species name of the type host.

Figures

FIGURE 29. Trouessartia pensylvanica sp. n., male. A—dorsal view, B—ventral view.

FIGURE 30. Trouessartia pensylvanica sp. n., female. A—dorsal view, B—ventral view.

FIGURE 31. Trouessartia pensylvanica sp. n., details. A, B—genu, tibia and tarsus I, II of male, respectively, C—tibia and tarsus IV of male, D—setae si, c2, c3 and sRIII of male, E—spermatheca and spermaducts, F—opisthosoma of female, dorsal view, G—opisthosoma and genital apparatus of male, ventral view.