Platyacarus picumnus Mironov, 2017

Mironov, Sergey V., Literak, Ivan, Sychra, Oldrich & Capek, Miroslav, 2017, Feather mites of the subfamily Proctophyllodinae (Acari: Proctophyllodidae) from passerines (Aves: Passeriformes) in Costa Rica, Zootaxa 4297 (1), pp. 1-105 : 18-21

Platyacarus picumnus Mironov sp. n.

( Figs. 7–9 )

Type material. Male holotype ( ZISP 6572 ), 10 male and 8 female paratypes from Dendrocolaptes picumnus Lichtenstein , MHK, 1820 ( Furnariidae ), COSTA RICA, Tapantí National Park , Sector Tapantí, Cordillera de Talamanca Mts., 09°46’N, 83°47’W, 9 August 2009, collectors I. Literak, O. Sychra and M. Capek.

Depository. Holotype, 8 male and 6 female paratypes (ZISP 6572–6586)—ZISP; 1 male and 1 female paratype—UMMZ (BMOC-15-1028-008), 1 male and 1 female paratype—IMUCR.

Description. MALE (holotype, range for 10 paratypes in parentheses). Idiosoma, length × width, 300 (290– 310) × 180 (170–180), length of hysterosoma 185 (180–190). Prodorsal shield: completely split into anterior and posterior pieces by poorly sclerotized transverse band at level of scapular setae, posterior margin with wide and rounded median extension, total length 105 (95–105), length of anterior part 62 (58–65), length of posterior part 31 (28–32), width of posterior part 110 (100–110), surface of both parts without ornamentation ( Fig. 7 A). Bases of scapular setae se separated by 75 (72–75). Scapular shields with poorly distinct inner borders. Setae c2 and cp on humeral shields. Setae c3 bristle-like, 15 (15–17) long. Distance between prodorsal and hysteronotal shields 15 (15–20). Hysteronotal shield: 180 (170–180) in length and 97 (90–98) in width; anterior margin straight, surface without ornamentation. Setae c1 on hysteronotal shield. Supranal concavity poorly expressed, 30 (27–32) long. Opisthosomal lobes roughly trapezoidal in form, with pair of truncate extensions bearing setae h2 and h3; terminal cleft wide semicircular, 25 (20–25) long and 45 (40–45) wide at level of setae h3. Interlobar membrane narrow, its terminal extensions at lobar apices (terminal lamellae) triangular, short, 10 (10–12) in length from level of seta h3 bases to apices, distance between inner margins of lamellae 29 (28–30). Setae f2 absent. Setae ps1 situated on lateral margins of terminal cleft, approximately at level of setae ps2. Setae h1 approximately at midlevel of supranal concavity. Distance between dorsal setae: c2:d2 50 (50–54), d2:e2 85 (75–85), e2:h3 42 (42–45), h2:h2 75 (72–75), h3:h3 52 (50–54), h1:h3 38 (35–38), d1:d2 18 (17–20), e1: e2 42 (37–42), ps1:h3 13 (12–14).

Epimerites I fused into a thick Y, with stem about half the total length of epimerites. Epimerites I, II thick, without large surface fields, with bases inflated and heavily sclerotized ( Fig. 7 B). Epimerites IVa small. Rudimentary sclerites rEpIIa present. Genital arch situated at midlevel of trochanters IV, small, 18 (17–20) long and 27 (27–30) wide; genital organ stylet-like, 40 (36–40) long, extending to midlevel of between setae g and ps3 ( Fig. 9 A). Distance from genital arch apex to level of setae h3 110 (100–110). Bases of genital papillae connected, situated on small oval plates at level of genital arch apex. Paragenital apodemes absent. Antero-lateral pieces of adanal shields absent; postero-medial pieces of adanal shield flanking anal opening and bearing setae ps3. Adanal suckers cup-shaped, 11 (11–12) in diameter; corolla smooth. Setae 4b slightly posterior to level of setae 3a. Distance between ventral setae: 4b:4a 32 (32–34), 4a:g 40 (37–40), g:g 19 (18–20), g:ps3 23 (22–24), ps3:ps3 13 (12–13), ps3:h3 55 (55–60).

Femora I, II without ventral crest. Tibiae I, II with noticeable ventral inflation. Solenidion σ 1 I half as long as genu I and situated at midlevel of this segment ( Fig. 9 B, C). Solenidion σ of genu III situated approximately at midlevel of segment. Legs IV with ambulacral disc extending slightly beyond level of terminal lamellae. Tarsus IV 30 (30–32) long, with ledge on dorsal margin, without apical processes; button-like seta d situated at base of this segment ( Fig. 9 D). Solenidion φ of tibia IV extending to tarsal apex. Length of solenidia: σ 1 I 10 (10–12), σ III 13 (12–14), φ IV 27 (25–28).

FEMALE (range for 8 paratypes). Idiosoma, length × width, 440–455 × 210–220, length of hysterosoma 300– 310. Prodorsal shield: shape and ornamentation as in male, total length 120–130, length of anterior part 75–80, length of posterior part 42–45, width of posterior part 125–130 ( Fig. 8 A). Bases of setae se separated by 90–95. Scapular and humeral shields with poorly distinct inner margins. Setae c2 and cp on humeral shields. Setae c3 bristle-like, 16–20 long. Distance between prodorsal and hysteronotal shields 30–40. Hysteronotal shields completely split into anterior and lobar shields. Anterior hysteronotal shield: 220–230 in length, 105–110 in width at anterior margin, 145–155 in wide in posterior part, anterior margin straight, posterior margin shallowly concave, surface without ornamentation. Setae c1 off hysteronotal shield near its anterior margin. Lobar shield: 65–70 in length and 100–110 in width. Terminal cleft wide U-shaped, lateral margins parallel-sided, 42–45 in length, 32–35 in width at midlevel. Supranal concavity absent. Setae h2 slightly thickened in basal part and with filiform apical part, 80–90 in length, 4–5 in width; setae h3 52–56 in length, about 1/3 of terminal appendages. Setae f2 absent. Setae h1 inserted on lobar shields, distant from its anterior margin. Setae ps1 on lateral margins of terminal cleft, closer to lobar apices than to level of setae h2. Distance between dorsal setae: c2:d2 72–75, d2:e2 120–125, e2:h2 60–64, h2:h 3 30–38, h1:h 2 27–30, h2:ps 1 17–20, d1:d 2 25–28, e1: e2 50–54, h1:h1 52–58, h2:h2 97–100.

Epimerites I fused into a V, with very thin connecting commissure. Epimerites I, II thick, without narrow surface fields, with bases inflated and heavily sclerotized ( Fig. 8 B). Epimerites IVa present, rudimentary. Epigynum semicircular, thick, with posterior ends bidentate and almost extending to level of anterior genital papillae, 40–46 in length, 75–80 in width. Genital papillae not connected at bases. Setae ps2 at middle of anal opening. Translobar apodemes fused to each other anterior to terminal cleft. Copulatory opening ventral, situated at anterior margin of fused translobar apodemes and covered with posterior ends of anal flaps. Head of spermatheca small U-shaped, poorly sclerotized; primary spermaduct without enlargement at head of spermatheca, medial part of primary spermaduct forming a loose skein; secondary spermaducts extremely short, 2–3 long ( Fig.9 E). Distance between pseudanal setae, ps2:ps2 57–60, ps3:ps 3 24–26, ps2:ps 3 10–12.

Legs I, II as in male. Solenidion σ 1 I about 2/3 length of genu I and situated at midlevel of this segment. Solenidion σ of genu III situated in basal part of this segment. Legs IV with ambulacral discs extending to level of setae h2. Solenidion φ of tibia IV about 1/3 of corresponding tarsus. Length of solenidia: σ 1 I 13–15, σ III 10–12, φ III 32 –34, φ IV 13–15.

Differential diagnosis. The new species, Platyacarus picumnus sp. n., belongs to the psilocoronius group in having a smooth corolla of adanal suckers and triangular terminal lamellae in males. Within this group, the new species is most similar to P. diversus Kudon, 1982 in having a wide terminal cleft with triangular terminal lamellae in males and the epigynum with bidentate tips in females. Platyacarus picumnus sp. n. differs from P. diversus by the following features: in males of P. picumnus , the genital papillae are connected at their bases and situated on small ovate plates, the anterior margin of the terminal cleft is semicircular, and the anterior margin of the hysteronotal shield is straight; in females, setae h1 are distant from the anterior edge of the lobar shield, and the terminal cleft is longer and wider (42–45 × 32–35 µm). In males of P. diversus , the genital papillae are free, the anterior margin of the terminal cleft is straight, and the anterior margin of the hysteronotal shield is slightly concave; in females, setae h1 are inserted on the anterior edge of the lobar shield, and the terminal cleft is smaller (c. 29 × 22 µm). In having the genital papillae connected in males, P. picumnus is similar to two other species of the psilocoronius group, P. longicolicus Kudon, 1982 and P. psilocoronius Kudon, 1982 . Males of P. picumnus are readily differentiated from these two species in having the terminal cleft almost semicircular vs. longitudinally ovate.

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

Figures

FIGURE 7. Platyacarus picumnus Mironov sp. n., male. A—dorsal view, B—ventral view.

FIGURE 8. Platyacarus picumnus Mironov sp. n., female. A—dorsal view, B—ventral view.

FIGURE 9. Platyacarus picumnus Mironov sp. n., details. A—opisthosoma of male, ventral view, B, C – legs I and II of male, dorsal view, D—tibia and tarsus IV of male, dorsal view, E – spermatheca and spermaducts.