Proterothrix megaceryle, Mironov & Galloway, 2021

Mironov, Sergey V. & Galloway, Terry D., 2021, Feather mites of the subfamily Pterodectinae (Acariformes: Proctophyllodidae) from passerines and kingfishers in Canada, Zootaxa 5016 (1), pp. 1-55 : 43-47

Proterothrix megaceryle sp. n.

( Figs. 25–27 )

Type material. Male holotype, 19 male and 20 female paratypes from Megaceryle alcyon (Linnaeus, 1758) ( Coraciiformes : Alcedinidae ), (BEKI/116/PWRC/15, SM 2631), CANADA, Manitoba, Winnipeg , 7 May 2015, coll. T.D. Galloway, C.R. Wushke.

Depository. Holotype, 7 male and 8 female paratypes — CNC, remaining paratypes — WRME and ZISP.

Description. MALE (holotype, range for 10 paratypes in parentheses) ( Figs. 25 , 27A–E ). Idiosoma, length × width, 350 (350–365) × 155 (150–160), length of hysterosoma 225 (220–240). Prodorsal shield: entire, anterolateral extensions long and pointed, lateral margins with deep incisions encompassing setae se and extending to setae si, posterior margin straight with thin medial extension, posterior angles nearly rectangular, surface without ornamentation, length 105 (100–110), width 83 (80–88). Setae ve absent. Bases of scapular setae se separated by 50 (50–58). Scapular shields well developed dorsally. Humeral shields represented by longitudinal sclerites situated dorsolaterally and bearing bases of setae c 2 in anteromesal angles. Bases of setae cp distant from ventral margins of humeral shields. Subhumeral setae c3 lanceolate, 23 (20–23) long, about 6 wide. Distance between prodorsal and hysteronotal shields about 30–35. Hysteronotal shield: anterior margin concave, anterior angles pointed, surface without ornamentation, greatest length 220 (220–230), width at anterior margin 80 (80–55). Lateral hysteronotal sclerites situated slightly anterior to the level of trochanters IV. Opisthosomal lobes short, roughly triangular, approximately as long as wide at base; posterolateral margins of lobes with extensions at bases of setae h2 and h3 with membranous edges; pointed inner angles of extensions bearing setae h3 constitute membranous lobar apices. Terminal cleft narrowly semi-ovate, length from anterior end to lobar apices 35 (32–35), greatest width 12 (10–12). Supranal concavity shaped as long inverted teardrop. Setae f2 at level of bases of setae ps2. Setae h1 situated at level of anterior end of terminal cleft. Setae h3 represented by macrosetae with membranous lanceolate enlargement in basal half, 160 (160–180) long, 15 (15–16) wide in basal part; macrosetae h2 simple, 140 (140–150) long; setae ps2 45 (40–45) long. Setae ps1 filiform, about 10 long, situated near margins of terminal cleft at level of setae h2. Distances between dorsal setae: c2:d2 82 (80–85), d2:e2 77 (75–88), e2:h3 58 (53–60), d1:d2 35 (28–37), e1: e2 15 (13–16), h2:h2 55 (50–55), h3:h3 35 (30–38), ps2:ps2 70 (68–72).

Epimerites I fused into a V, fused part connected with middle parts of epimerites II by a pair of transverse sclerotized bands. Epimerites II of moderate size, not connected with other epimerites. Coxal fields I, II without extensively sclerotized areas. Rudimentary sclerites rEpIIa barely distinct. Coxal fields I closed, coxal fields II, III open. Bases of epimerites IV with small sclerotized areas partly flanking trochanters IV. Epimerites IVa small, not extending to setae 4a. Genital arch of moderate size, 23 (20–25) × 30 (28–30); aedeagus sword-shaped, 65 (65–70) long, extending closely to anterior end of anal slit; basal sclerite of genital apparatus small, semicircular ( Fig. 27A ). Genital papillae not connected at bases, situated at level of apex of genital arch. Paragenital sclerites at tips of genital arch minute. Pregenital sclerite absent. Genital shield absent. Adanal suckers cylindrical, slightly enlarged in basal part, greatest diameter16 (16–19); corolla 13 (13–15) in diameter, with 11–13 denticles; surrounding membrane smooth. Adanal shields represented by two pairs of sclerites: anterolateral sclerites shaped as oblique poorly sclerotized sticks, and median sclerites shaped as small plates with strongly uneven margins and bearing setae ps3. Opisthoventral shields absent. Setae 4b situated slightly posterior to level of setae 3a. Distance between ventral setae: 4b: 3a 7 (5–10), 4b:4a 40 (38–40), 4a:g 47 (43–48), g:ps3 35 (34–38), ps3:ps3 53 (53–58), ps3:h3 15 (15–17).

Femora I, II with narrow ventral crests, other segments of legs I, II without processes ( Fig. 27B, C ). Solenidion σ of genu I slightly longer than half the length of this segment and situated at its midlength. Genual setae cG I, II and mG I, II filiform. Setae d of tarsi II, III much shorter than corresponding setae f. Solenidion φ of tibia IV extending to midlength of disc. Tarsus IV 25 (23–25) long, without apical process; setae d, e button-like; seta d in basal half of this segment ( Fig. 27E ). Length of solenidia: ω1 I 13 (13–15), ω1 II 12 (9–12), σ I 15 (15–18), σ III 13 (13–16), φIV 32 (32–35).

FEMALE (range for 10 paratypes) ( Figs. 26 , 27F, G ). Idiosoma, length × width, 470–520 × 185–230, length of hysterosoma 320–360. Prodorsal shield: shaped as in male, surface without ornamentation, 125–130 × 105–130. Setae ve absent. Bases of setae se separated by 70–85. Scapular shields well developed dorsally. Humeral shields represented by small longitudinal sclerites situated dorsolaterally. Setae c 2 in anteromesal angles of humeral shield, setae cp on ventral margins of this shield. Setae c3 lanceolate, 22–25 long, about 7–7.5 wide. Distance between prodorsal and hysteronotal shields 35–50. Anterior and lobar parts of hysteronotal shield separated dorsally by narrow transverse band of soft tegument and weakly connected ventrolaterally. Anterior hysteronotal shield: nearly rectangular, anterior margin concave, with slightly concave lateral margins slightly concave at level of trochanters III, and IV, posterior margin concave and unevenly sinuous, surface without ornamentation, greatest length 260– 270, width at anterior margin 100–120 ( Fig. 26A ). Length of lobar region 60–68, greatest width 104–110. Terminal cleft narrow V-shaped, 35–40 long. Lobar shield split into two pieces or their anteromedian ends connected by thin transverse bridge; surface without ornamentation. Supranal concavity absent. Setae h1 on lobar shields near their anterior margin; setae h1 and f2 arranged in a low trapezoid. Setae h2 spindle-like with filiform apex, 70–90 long, and 6–7 wide. Setae ps1 situated on inner margins of opisthosomal lobes, closer to lobar apices, than to level of setae h2. Setae h3 26–30 long, about 1/6th the length of terminal appendages. Distances between dorsal setae: c2: d2 100–115, d2:e2 115–125, e2:h2 65–73, h2:h3 20–30, d1:d2 30–32, e1: e2 22–32, h1:h2 20–36, h1:h1 48–64, h2: h2 85–95, h2:ps1 8–13.

Epimerites I fused into a narrow U, connecting commissure thin, posterior end of these epimerites with narrow small hook-like extensions curved laterally ( Fig. 26B ). Lateral parts of coxal fields I, II without extensive sclerotized areas. Epimerites IVa absent. Translobar apodemes of opisthosomal lobes wide, not fused to each other anterior to terminal cleft. Epigynum with small lateral extensions, greatest width 82–105; apodemes of oviporus fused with epimerites IIIa. Pseudanal setae filiform, setae ps2 situated at level of posterior half of anal opening and widely separated from each other; distance between pseudanal setae: ps2:ps2 53–67, ps3:ps3 22–25, ps2:ps3 25–28. Copulatory opening situated between inner ends of translobar apodemes. Primary spermaduct without enlargement; continuation of primary spermaduct inside spermatheca with ovate enlargement; well sclerotized part of secondary spermaducts about 10 long ( Fig. 27G ).

Legs I, II as in male. Solenidion σ of genu I approximately 2/3rd the length of this segment and situated at its midlevel. Genual setae cG I, II, mG I, II as in male. Setae d of tarsi II–IV much shorter than corresponding setae f. Genu IV not inflated. Lengths of solenidia: ω1 I 15–17, ω1 II 8–11, σ I 19–24, σ III 15–18, φ III 35–40, φ IV 15–19.

Differential diagnosis. Proterothrix megaceryl e sp. n., belongs to the schizothyra species group in having coxal fields III in males open and the terminal cleft in females with distinctly divergent margins (V-shaped). Among four previously known species of this group, the new species is closest to P. schizothyra ( Gaud, 1952) from the Malachite Kingfisher, Corythornis cristatus (Pallas, 1764) , in having the following features: in both sexes, the prodorsal shield has a narrow median extension on the posterior margin, rectangular posterior corners and large incisions around setae se; in males, the adanal shields of the anterior pair are oblique, and coxal setae 3a and 4b are arranged in an almost transverse row. Females of P. megaceryle are also similar to P. allothyra Gaud, 1979 (known only from females) from the Giant Kingfisher, Megaceryle maxima (Pallas, 1769), by the characteristics of the prodorsal shield as described above. Proterothrix megaceryl e is distinguished from P. schizothyra in having the following features: in males, the genital shields (les apodèmes sous-génitaux of Gaud 1979) are absent, the anterior adanal shields are short with their anterior extremities distant from the midline, and epimerites I are fused into a U and connected to epimerites II by narrow sclerotized bands; in females, the supranal concavity is absent and the lobar apices are roughly rounded. In males of P. schizothyra , the genital shields are shaped as large and elongated triangular plates bearing setae g, the anterior adanal shields are long with the anterior extremities almost touching at midline, and epimerites I are fused into a U and not connected to epimerites II; in females, the supranal concavity is well marked and ovate in shape, and the lobar apices are distinctly angular. The absence of the genital shields in males and supranal concavity in females separate P. megaceryle from all previously known species of the schizothyra group.

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

Figures

FIGURE 25. Proterothrix megaceryle sp. n., male. A—dorsal view, B—ventral view.

FIGURE 26. Proterothrix megaceryle sp. n., female. A—dorsal view, B—ventral view.

FIGURE 27. Proterothrix megaceryle sp. n., details. A—opisthosoma of male, ventral view, B–D—legs I–III of male, respectively, E—tibia and tarsus IV of male, F—tibia and tarsus IV of female, G—spermatheca and spermaducts.