Amerodectes helmitheros, 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 : 222-226

Amerodectes helmitheros sp. n.

( Figs. 10–12 )

Type material. Male holotype (BMOC-16-0825-022), 6 male and 3 female paratypes from Helmitheros vermivorum (Gmelin, 1789) ( Passeriformes : Parulidae ), USA, Georgia, Statesboro, Georgia Southern University campus, 32°25'15"N, 81°47'22"W, 14 April 2014, C.R. Chandler.

Depository. Holotype, 4 male and 2 female paratypes—BMOC, 2 male and 1 female paratypes—ZISP.

Description. MALE (holotype, range for 6 paratypes in parentheses). Idiosoma, length × width, 360 (340– 360) × 130 (125–140), length of hysterosoma 240 (220–245). Prodorsal shield: entire, anterolateral extensions acute or rectangular, lateral margins rough and slightly concave at level of scapular setae, posterior margin straight, posterior angles rounded, surface with few minute lacunae in anterior half or without them, length 110 (105–110), width 105(95–110) ( Fig. 10A ). Setae ve rudimentary, represented by alveoli. Bases of scapular setae se separated by 55 (52–55). Scapular shields narrow, scarcely developed dorsally. Humeral shields absent. Setae cp and c2 situated on striated tegument. Subhumeral setae c3 lanceolate, 25 (22–25) × 7.5 (7–8). Hysteronotal shield: greatest length 220 (220–245), width at anterior margin 100 (95–100), anterior margin straight or lightly concave, surface without ornamentation. Distance between prodorsal and hysteronotal shields about 10–15. Opisthosomal lobes approximately as long as wide at base; posterior margins of lobes roughly rounded, with small apical extensions at bases of setae h3. Terminal cleft shaped as an inverted U with divergent distal halves of branches, 30 (25–30) long. Supranal concavity semicircular. Setae f2 anterior to bases of setae ps2. Setae h1 situated at level of supranal concavity. Setae h3 spiculiform, slightly curved, 22 (20–25) long; setae ps2 82 (80–90) long. Setae ps1 filiform, about 10 long, situated near margins of terminal cleft approximately at level of setae ps2. Distances between dorsal setae: c2:d2 95 (85–95), d2:e2 87 (80–90), e2:h3 55 (50–55), d1:d2 32 (28–34), e1: e2 25 (22–28), h1:ps2 30 (26– 30), h2:h2 52 (47–55), h3:h3 37 (35–38), ps2:ps2 62 (57–64).

Epimerites I fused into a V, fused part with three small lateral extensions and very short median one (lateral ones in some specimens poorly expressed) ( Fig. 10B ). Epimerites II with small triangular sclerotized fields on inner margins. Coxal fields I, II without extensively sclerotized areas. Rudimentary sclerites rEpIIa absent. Coxal fields I–III open. Coxal fields IV without sclerotized areas at bases of trochanters IV. Epimerites IVa absent. Genital arch of moderate size, 25 (24–26) × 42 (40–43); aedeagus sword-shaped, 107 (100–108) long, extending to anterior end of terminal cleft; basal sclerite of genital apparatus large, almost circular in shape; ( Fig. 12A ). 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 areas of opisthosoma and distal half of opisthosomal lobes; inner margins of these shields at level of anal suckers with roughly trapezoidal extensions bearings setae ps3. Setae 4b situated slightly posterior to level of setae 3a; setae ps3 approximately at midlevel of adanal suckers. Distance between ventral setae: 4b: 3a 10 (8–10), 4b:4a 42 (37–43), 4a:g 40 (38–40), g:ps3 55 (47–55), ps3:ps3 52 (50–55), ps3:h3 37 (32–37).

Femora I, II with narrow ventral crests, other segments of legs I, II without processes ( Figs. 12B, C ). Solenidion σ1 of genu I longer than half of this segment and situated approximately at its midlevel. Genual setae cG I, II and mG I filiform, setae mG II slightly thickened basally. Setae d of tarsi II, III much shorter than corresponding setae f. Solenidion φ of tibia IV extending to proximal margin of ambulacral disc. Tarsus IV 25 (22– 25) long, without apical process; seta d at midlength of this segment ( Fig. 12D ). Length of solenidia: ω 1 I 13 (11– 13), ω 1 II 10 (8–10), σ 1 I 13 (12–14), σ III 10 (9–10), φ IV 25 (22–25).

FEMALE (range for 3 paratypes). Idiosoma, length × width, 460–470 × 130–140, length of hysterosoma 330– 340. Prodorsal shield: anterolateral extension short and acute, lateral margins with narrow incisions posterior to scapular setae and almost extending to bases of setae si, posterior margin with pair of shallow concavity and short and wide median extension, surface without ornamentation, 115–120 × 110–115. Setae ve rudimentary, represented by alveoli. Bases of setae se separated by 65–68 Scapular shields narrow, scarcely developed dorsally. Humeral shields absent. Setae cp and c2 situated on striated tegument. Setae c3 lanceolate, 21–23 × 7–8.5. Anterior and lobar parts of hysteronotal shield separated dorsally by narrow transverse band of soft tegument and remain connected ventrolaterally ( Fig. 11A ). Anterior hysteronotal shield noticeably attenuate to posterior end, anterior margin straight, surface without ornamentation, greatest length 240–250, width at anterior margin 110–115. Length of lobar region 90–95, greatest width 70–75. Terminal cleft narrow, with lateral margins almost touching anteriorly and slightly divergent posteriorly, 60–65 long. Lobar shield split longitudinally or anterior ends of its pieces connected by weakly sclerotized transverse bridge; anterior ends of these pieces with 1-2 ovate lacunae or without them. Supranal concavity marked by heavily sclerotized patch of triangular form between anterior ends of lobar shield. Setae h1 situated slightly posterior to level of supranal concavity; setae h1 and f2 arranged in a low trapezium. Setae h2 spindle-like, 42–45 × 7.5–8. Setae ps1 situated near inner margins of opisthosomal lobes, approximately equidistant betwee lobar apices and setae h2. Setae h 3 12–14 long, about 1/8 the length of terminal appendages. Distances between dorsal setae: c2:d2 105–110, d2:e2 100–105, e2:h2 58–62, h2:h3 45–48, d1:d2 48–52, e1: e 2 26–30, h1:h 2 18–20, h1:h 1 26–29, h2:h2 60–63, h2:ps 1 23–25.

Epimerites I fused into a Y with very short stem ( Fig. 11B ). Lateral parts of coxal fields I, II without large sclerotized areas. Epimerites IVa absent. Translobar apodemes of opisthosomal lobes present, wide, not fused to each other anterior to terminal cleft. Epigynum without lateral extensions, greatest width 50–55; apodemes of oviporus free from epimerites IIIa. Pseudanal setae filiform, setae ps2 situated at level of posterior margin of anal opening and widely separated from each other; distance between pseudanal setae: ps2:ps 2 28–30, ps3:ps 3 19–20, ps2:ps 3 24–26. Primary spermaduct without enlargement near head of spermatheca; continuation of primary spermaduct in spermatheca narrowly ampuliform, with strongly sclerotized wall; secondary spermaducts 30 long ( Fig. 12E ).

Femora I, II with ventral crest, other segments of legs I, II without processes. Solenidion σ1 of genu I slightly longer than half 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 slightly inflated dorsally. Lengths of solenidia: ω 1 I 12–13, ω1 II 9–10, σ 1 I 14–15, σ III 10–11, φ III 25–27, φ IV 8–10.

Differential diagnosis. The new Amerodectes helmitheros sp. n. is most similar to A. wilsoniae described from Setophaga citrina (Boddaert) (Parulidae) in Cuba ( Mironov & González-Acuña 2011). In females of these species, the lobar shield is split longitudinally and the distal part of the primary spermaduct is enlarged; in males, the aedeagus extends to the anterior end of the terminal cleft, epimerites I are not connected with II, and setae h3 are short and slightly exceed half the distance between their bases. Amerodectes helmitheros differs from that species by the following features: in males, the apices of opisthosomal lobes are slightly attenuate and bear the bases of setae h3, the fused part of epimerites I has a pair of short lateral extensions; in females, the lateral margins of the prodorsal shield have a narrow incision posterior to the bases of setae se, the anterior hysteronotal shield is devoid of lacunae, the proximal part of the primary spermaduct does not have any noticeable enlargement, and the secondary spermaducts are about 30 µm. In males of A. wilsoniae , the posterior margin of opisthosomal lobes is roughly rounded, with a pair of small extensions bearing setae h3 and h2, the fused part of epimerites I is shaped as a short stem without lateral extensions; in females, the lateral margins of the prodorsal shield are slightly concave, the anterior hysteronotal shield bears numerous circular lacunae in the posterior half, the proximal part of the primary spermaduct has a narrow ampuliform enlargement, and the secondary spermaducts are 10–15 µm long.

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

Figures

FIGURE 10. Amerodectes helmitheros sp. n., male. A—dorsal view, B—ventral view.

FIGURE 11. Amerodectes helmitheros sp. n., female. A—dorsal view, B—ventral view.

FIGURE 12. Amerodectes helmitheros 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.