Amerodectes hylocichlae, Mironov & Chandler, 2017

Mironov, Sergey V. & Chandler, C. Ray, 2017, New feather mites of the genus Amerodectes Valim and Hernandes (Acariformes: Proctophyllodidae) from passerines (Aves: Passeriformes) in Georgia, USA, Zootaxa 4344 (2), pp. 201-245 : 213-217

Amerodectes hylocichlae sp. n.

( Figs. 4–6 )

Type material. Male holotype (BMOC-16-0825-024), 16 male and 9 female paratypes from Hylocichla mustelina (Gmelin, 1789) ( Passeriformes : Turdidae ), USA, Georgia, Statesboro, Georgia Southern University campus, 32°25'15"N, 81°47'22"W, 16 October 2013, coll. C.R. Chandler.

Depository. Holotype, 8 male and 10 female paratypes—BMOC, 8 male and 9 female paratypes—ZISP.

Description. MALE (holotype, range for 10 paratypes in parentheses). Idiosoma, length × width, 430 (405– 430) × 160 (150–160), length of hysterosoma 280 (265–285). Prodorsal shield: entire, anterolateral extensions rounded, lateral margins slightly concave at level of scapular setae, posterior margin straight, posterior angles with rounded ends, length 125 (120–130), width 125 (120–135), entire surface with numerous minute circular lacunae ( Fig. 4A ); Setae ve rudimentary, represented by alveoli. Bases of scapular setae se separated by 73 (62–75). Scapular shields narrow. Humeral shields small, represented by narrow longitudinal sclerites dorsal to bases of setae cp and c3. Setae cp on ventral margin of humeral shield, setae c2 on soft tegument near anterior end of these shields. Subhumeral setae c3 lanceolate, 28 (25–29) × 10 (8–10). Hysteronotal shield: anterior margin straight, entire surface with numerous minute circular lacunae, greatest length 290 (275–290), width at anterior margin 125 (115–130). Distance between prodorsal and hysteronotal shields 10–15. Opisthosomal lobes approximately as long as wide at base; posterior margins of lobes with a pair of small spine-like extensions at bases of seta h3 and with large and curved spine at base of seta h2. Terminal cleft shaped as an inverted U with slightly divergent branches, 37 (35–38) long. Supranal concavity small semicircular, poorly defined. Setae f2 anterior to bases of setae ps2. Setae h1 situated at level of anterior end of terminal cleft. Setae h3 narrowly lanceolate, 25 (23–27) long; setae ps2 95 (80–95) long; setae ps1 filiform, about 10 long, situated on lateral margins of terminal cleft approximately at level of setae h2 and ps2. Distances between dorsal setae: c2:d2 100 (95–100), d2:e2 105 (100–105), e2:h3 65 (58– 65), d1:d2 35 (28–35), e1: e2 33 (32–36), h1:ps2 30 (25–30), h2:h2 70 (60–70), h3:h3 38 (35–40), ps2:ps2 88 (85– 90).

Epimerites I fused into a V, fused part connected to medial parts of epimerites II by narrow transverse bands ( Fig. 4B ). Coxal fields I, II without extensively sclerotized areas. Rudimentary sclerites rEpIIa absent. Coxal fields I closed, coxal fields II, III open. Coxal fields IV with sclerotized areas at bases of trochanters IV. Epimerites IVa rudimentary. Genital arch of moderate size, 25 (24–26) × 42 (40–42); basal sclerite of genital apparatus roughly rectangular; aedeagus sword-shaped, 102 (87–105) long, extending to anterior margins of anal suckers ( Fig. 6A ).

Genital papillae not connected at bases. Genital and adanal shields absent. Adanal suckers 15 (14–15) in diameter, corolla smooth, surrounding membrane with radial striae. Opisthoventral shields occupying lateral area of opisthosoma and distal half of opisthosomal lobes; inner margins of these shields posterior to adanal suckers with oblique extensions having rough borders and bearings setae ps3; anterior margin on these shields on lobes heavily sclerotized and unevenly dentate. Setae 4b situated posterior to level of setae 3a. Distance between ventral setae: 4b: 3a 10 (8–10), 4b:4a 45 (42–45), 4a:g 53 (52–55), g:ps3 68 (65–70), ps3:ps3 73 (70–75), ps3:h3 34 (32–35).

Femora I, II with narrow ventral crests, other segments of legs I, II without processes ( Figs. 6B, C ). Solenidion σ1 of genu I shorter than half the length of this segment, situated at its midlevel. Genual setae cG I, II and mG I filiform, setae mG II slightly thickened basally. Setae d of tarsi II, III shorter than corresponding setae f. Solenidion φ of tibia IV extending to proximal midlevel of ambulacral disc. Tarsus IV 30 (28–30) long, with short claw-like apical process; seta d in basal half of this segment ( Fig. 6D ). Length of solenidia: ω 1 I 18 (15–18), ω 1 II 13 (12–13), σ 1 I 11 (9–11), σ III 13 (12–13), φ IV 35 (32–36).

FEMALE (range for 10 paratypes). Idiosoma, length × width, 535–555 × 195–210, length of hysterosoma 375–385. Prodorsal shield: shape and surface as in male, 145–150 × 150–160. Setae ve rudimentary. Bases of setae se separated by 82–95. Scapular shields narrow, scarcely developed dorsally. Humeral shields represented by narrow longitudinal sclerites. Setae cp situated on ventral margins of humeral shields, c2 on striated tegument near anterior ends of these shields. Setae c3 lanceolate, 38–30 × 9–10. Anterior and lobar parts of hysteronotal shield separated dorsally by narrow transverse band of soft tegument, but remain connected ventrolaterally. Anterior hysteronotal shield nearly rectangular, slightly attenuate to posterior end, anterior margin straight, greatest length 295–310, width at anterior margin 145–165, surface with numerous minute circular lacunae ( Fig. 5A ). Length of lobar region 100–105, greatest width 105–115. Terminal cleft narrow, with lateral margins parallel-sided and almost touching in anterior half and slightly divergent in posterior part, 58–62 long. Lobar shield entire, with shallow median concavity on anterior margin, anterior part with large circular and ovate lacunae. Supranal concavity circular, well outlined. Setae h1 at level of supranal concavity; setae h1 and f2 arranged in almost transverse line. Setae h2 spindle-like, with acute apices, 78–82 × 9–10. Setae ps1 situated on inner margins of opisthosomal lobes, close to lobar apices. Setae h 3 20–25 long, about 1/8 the length of terminal appendages. Distances between dorsal setae: c2:d2 130–135, d2:e2 110–135, e2:h2 80–85, h2:h3 38–42, d1:d2 57–68, e1: e2 33–48, h1:h2 34–36, h1:h 1 30–32, h2:h2 85–90, h2:ps 1 26–30.

Epimerites I fused into a V, fused part with a pair of oblique lateral extensions and median one (poorly expressed in some specimens) ( Fig. 5B ). Lateral parts of coxal fields I, II without large sclerotized areas. Epimerites IVa poorly defined. Translobar apodemes of opisthosomal lobes wide and fused to each other anterior to terminal cleft. Epigynum with small lateral ledges, greatest width 78–82; apodemes of oviporus free from epimerites IIIa. Pseudanal setae filiform, setae ps2 situated posterior to anal opening and widely separated from each other; distance between pseudanal setae: ps2:ps2 45–50, ps3:ps 3 14–16, ps2:ps3 50–58. Primary spermaduct with narrow ampuliform enlargement near head of spermatheca; continuation of primary spermaduct in spermatheca narrowly cone-like with finger-like festoons on free margin; secondary spermaducts about 10 long ( Fig. 6E ).

Femur II with narrow ventral crest, other segments of legs I, II without processes. Solenidion σ1 of genu I half as long as this segment and situated at its midlevel. Genual setae cG I, II, mG I, II as in male. Seta d and f of tarsi II subequal, setae d of tarsi III, IV much shorter than corresponding setae f. Genu IV dorsally inflated, with narrow dorsal crest. Lengths of solenidia: ω 1 I 12–15, ω 1 II 10–13, σ 1 I 10–13, σ III 8–12, φ III 36 –40, φ IV 13–15.

Differential diagnosis. Amerodectes hylocichlae sp. n. is close to A. plumbeus described from Turdus plumbeus Linnaeus in Chile ( Mironov & González-Acuña 2011). In both sexes of these species, the entire surface of the dorsal shields is completely covered with numerous circular lacunae; in males, the fused part of epimerites I is connected with middle parts of epimerites II, the opisthosomal lobes bear a large and slightly curved spine-like extension at bases of setae h2, and the bases of trochanters IV are flanked by triangular sclerotized areas. Amerodectes hylocichlae sp. n. differs from A. plumbeus by the following features: in males, the aedeagus is shorter and extends only to the anterior margins of adanal suckers, setae h3 is shorter (23–27 µm long) with length less than distance between their bases, the anterior margins of opisthoventral shields covering opisthosomal lobes are heavily sclerotized and bear small irregular denticles; in females, setae h2 have acute tips and are 1.5 times longer than the terminal cleft, the fused part of epimerites I has a pair of short lateral extensions. In males of Amerodectes plumbeus , the aedeagus extends to the midlevel of the adanal suckers, setae h3 are 38–42 µm long and almost equal in length to the distance between their bases, the anterior margins of opisthoventral shields are smooth; in females, setae h2 have rounded tips and are approximately equal in length to the terminal cleft, and the fused part of epimerites I lacks lateral extensions.

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

Figures

FIGURE 4. Amerodectes hylocichlae sp. n., male. A—dorsal view, B—ventral view.

FIGURE 5. Amerodectes hylocichlae sp. n., female. A—dorsal view, B—ventral view.

FIGURE 6. Amerodectes hylocichlae sp. n., details. A—opisthosoma of male, ventral view, B, C—legs I, II of male, respectively, D—tibia and tarsus IV of male, E—spermatheca and spermaducts.