Trouessartia cryptocaudata Mironov and Galloway, 2019

Mironov, Sergey V. & Galloway, Terry D., 2019, Feather mites of the genus Trouessartia Canestrini (Acariformes: Trouessartiidae) from swallows (Passeriformes: Hirundinidae) in Canada, Zootaxa 4568 (1), pp. 1-39 : 15-19

Trouessartia cryptocaudata Mironov and Galloway sp. n.

( Figs. 7–9 )

Type material. Holotype male ( CNC758975 ), 10 male and 10 female paratypes from Progne subis (Linnaeus, 1758) ( Passeriformes : Hirundinidae ), CANADA, Manitoba, Winnipeg , 30 April 1999, coll. T.D. Galloway.

Depositories. Holotype, 4 male and 4 female paratypes—CNC, remaining paratypes—BMOC, WRME and ZISP.

Description. MALE (holotype, ranges for 10 paratypes in parentheses) ( Figs. 7 , 9 A–F). Length of idiosoma from anterior end to lobar apices excluding lamellae 500 (475–525), width of idiosoma at level of humeral shields 235 (220–250). Length of hysterosoma from level of sejugal furrow to lobar apices 335 (325–360). Prodorsal shield: length along midline 145 (140–160), greatest width posterior to level of scapular setae 185 (180–190), anterior part at level of trochanters II not narrowed, antero-lateral extensions fused with bases of epimerites Ia between legs I and II, lateral margins fused with antero-mesal angles of scapular shields, posterior margin straight, surface with small weakly distinct lacunae. Internal scapular setae si spiculiform, 20 (18–23) long, separated by 65 (65–68); external scapular setae se separated by 120 (115–125). Setae c2 thin spiculiform, 20 (15–23) long, situated in antero-median angle of humeral shields. Setae c3 narrowly lanceolate, with acute apex, 20 (20–23) long. Hysteronotal shield completely separated into prohysteronotal and lobar parts, total length from anterior margin to lobar apices excluding lamellae 335 (325–355). Prohysteronotal shield: length along midline 205 (195–210), width at anterior margin 195 (190–205), lateral margins shallowly concave at level of trochanters III, dorsal hysterosomal apertures (DHA) present, entire area with barely distinct small lacunae. Dorsal setae d1, d2, e2 present. Length of lobar shield excluding terminal lamellae 130 (125–145). Opisthosomal lobes several times longer than wide, widely separated by semi-ovate terminal cleft; length of cleft from anterior end to lobar apices (bases of setae h3) 125 (120–130), length of cleft from anterior end to lamellar apices 145 (145–160), greatest width (at level of setae h3) 80 (65–80). Terminal lamellae semi-ovate, with rounded and smooth posterior margins, length from bases of setae h3 to lamellar apices 33 (32–40), greatest width 40 (35–40). Distance between dorsal setae: c2:d2 77 (70–80), d2:e2 115 (110–120), e2:h2 105 (100–112), h2:h3 25 (25–30), h2:h2 125 (115–125), h3:h3 115 (105–110), d1:d2 48 (45–50), e1: e2 57 (55–55), h1:h2 10 (10–13), ps1:h3 5 (5–8).

Epimerites I free. Rudimentary sclerites rEpIIa large triangular, with two acute inner angles. Genital apparatus situated between levels of trochanters III and IV, length excluding basal sclerite 55 (50–58), greatest width 54 (45– 52). Epiandrum present. Latigenital sclerite absent. Anterior and posterior genital papillae equal in size and situated almost equidistant from midline. Setae g long, filiform, with almost touching bases. Genital shield absent.

Adanal apodemes heavily sclerotized, without apophyses, lateral margins with vestigial membranes. Translobar apodeme absent. Adanal shields bearing setae ps3 shaped as minute sclerites of irregular form. Anal suckers 20 (18–20) in diameter. Inner ends of epimerites IIIa with L-shaped apices bent antero-laterally and extending beyond levels of setae 3a and 4b, posterior margin of these epimerites without extensions. Epimerites IVa absent. Setae 4b situated slightly posterior to level of setae 3a; setae g approximately at level of setae 4a. Distance between ventral setae: 4b:3a 7.5 (7–9), 4b:g 70 (62–70), g:ps3 90 (87–90), ps3: h3 110 (105–120).

Setae cG, mG of genua I, II filiform. Genual solenidia σ 1 I and σ II approximately at midlength of corresponding genua. Trochanteral setae sR III narrowly lanceolate, with bidentate apex, 15 (13–15) long. Legs IV with ambulacral disc extending beyond level of setae h2. Tarsus IV 35 (35–38) long; modified setae d barrel-shaped, with discoid cap, situated in distal one thirds of this segment; modified setae e button-like, without cap, situated apically. Length of solenidia: σ 1 I 40 (40–47), σ II 10 (10–13), σ III 20 (17–22), φ IV 30 (27–30).

FEMALE (range for 10 paratypes) ( Figs. 8A, B , 9 G–I). Length of idiosoma from anterior end to apices of hyaline lobar processes 535–565, width at level of humeral shields 220–230. Length of hysterosoma from level of sejugal furrow to apices of lobar processes 370–400. Prodorsal shield: shape and ornamentation as in male, 145– 160 long, 180–190 wide. Setae si thin spiculiform, 18–23 long, separated by 67–70; setae se separated by 115–125. Setae c2 thin spiculiform, 18–23 long, situated in antero-medial angle of humeral shields. Setae c3 narrowly lanceolate, with acute apex, 20–23 long. Hysteronotal shield: length from anterior margin to bases of setae h3 360– 385, width at anterior margin 185–195, lateral margins shallowly concave at level of trochanters III, DHA present, median area from level of setae cp to setae h2 with numerous ovate lacunae increasing in size to posterior part of this area. Dorsal setae d1, d2, e2 present. Setae f2 present, minute. Setae h1 short filiform, about 5 long, situated antero-mesal to bases of setae h2, 14–15 from corresponding lateral margins of hysteronotal shield. Width of opisthosoma at level of setae h2 100–110. Setae psl positioned dorsal, close to outer margins of opisthosomal lobes. Supranal concavity open posteriorly into terminal cleft. Length of terminal cleft from anterior margin to lobar apices 145–160, length from free margin of interlobar membrane to lobar apices 110–120, width of cleft at level of setae h3 32–38. Interlobar membrane occupying anterior 1/6th of terminal cleft, distance from free margin of membrane to lobar apices 110–120. External copulatory tube short finger like, situated ventrally, inside coneshaped pocket opened at free margin of interlobar membrane. Distance between dorsal setae: c2:d2 75–85, d2:e2 112–120, e2:h2 60–65, h2:h3 77–82, h2:h2 80–85, h3:h3 45–55, d1:d2 52–57, e1: e2 47–52, h1:h 2 18–20, h1:h1 55–58, ps1:h 3 10–12.

Epimerites I free. Epigynum 35–38 long, 82–85 wide. Head of spermatheca with short non-dentate collar, with 6-8 rounded denticles ( Fig. 9H ), proximal part of primary spermaduct slightly enlarged, secondary spermaducts 35–40 long, distal part of primary spermaduct curved S-likely and noticeably sclerotized. Inner margins of epimerites IIIa with long finger-like extension. Epimerites IVa present, long. Anal opening with triangular adanal sclerites.

Legs I, II as in males. Trochanteral setae sR III narrowly lanceolate, bidentate apically, 12–15 long. Legs IV with ambulacral disc extending to midlevel between setae h2 and h3. Length of solenidia: σ 1 I 42–45, σ II 10–12, σ III 20–22.

Differential diagnosis. The new species, Trouessartia cryptocaudata sp. n., is close to T. stelgidopteryx and T. bochkovi (described above) in having the opisthosomal lobes long and widely separated by the terminal cleft in males. Trouessartia cryptocaudata differs from these species by the characters as follows: in both sexes, the prodorsal shield is fused with the antero-mesal angles of the scapular shields; in males, setae d of tarsus IV is situated in the distal half of this segment, the lobar shield is completely split longitudinally, and the length of the idiosoma is 475–525 µm; in females, setae h1 are filiform, the distal end of the primary spermaduct is S-shaped, the external copulatory tube is finger-like and hidden ventrally in a cone-shaped pocket ( Fig. 9I ). In both sexes of T. stelgidopteryx and T. bochkovi , the prodorsal shield is free from the scapular shields; in males, seta d of tarsus IV is situated in the proximal half of this segment, the pieces of lobar shield are connected at antero-median angles, and the length of the idiosoma is 380–470 µm; in females, setae h1 are lanceolate, the distal end of the primary spermaduct is straight, the external copulatory tube is short spine-like and situated on the free margin of the interlobar membrane.

Etymology. The specific epithet is derived from crypto (L. hidden) and caudus (L. tail) and refers to hidden external copulatory duct in females.

Figures

FIGURE 7. Trouessartia cryptocaudata sp. n., male. A—dorsal view, B—ventral view.

FIGURE 8. Trouessartia cryptocaudata sp. n., female. A—dorsal view, B—ventral view.

FIGURE 9. Trouessartia cryptocaudata sp. n., details. A, B—genu, tibia and tarsus I and II of male, respectively, C, D—tibia and tarsus III and IV of male, respectively, E—genital apparatus and opisthosoma of male, ventral view, F—setae si, c2, c3 and sRIII of male, G—tibia and tarsus IV of female, H—spermatheca and spermaducts, I—area with distal end of primary spermaduct, ventral view. Abbreviations: ap—apodeme of aedeagus, bs—basal sclerite, cp—copulatory pocket, ct—external copulatory tube, ea—epiandrum, is—intermedial sclerite, pd—distal end of primary spermaduct, pm—paramere.