Dolichodectes neotropicus Hernandes & Valim, 2006

Hernandes, Fábio A. & Valim, Michel P., 2006, Two new species of the feather mite subfamily Pterodectinae (Acari: Astigmata: Proctophyllodidae) from Brazil, Zootaxa 1235 (1), pp. 49-61 : 55-58

Dolichodectes neotropicus Hernandes & Valim sp. n.

( Figs. 8–17 )

Type material: 1 male holotype, 5 male and 13 female paratypes, collected from the Lesser Elaenia , Elaenia chiriquensis Lawrence ( Passeriformes , Tyrannidae ), Fazenda Agua Limpa, Brasília, D.F., Brazil (15 S 57’–47 W 56’); 07.VIII.2002, coll. M.F. Kanegae. Holotype male and most paratypes are deposited at CAIOC; a paratype female and male deposited at DZSJRP.

Male holotype ( Figs. 8–9 , 12–14, 16–17 ). (range of 5 paratypes indicated in parenthesis). Length of idiosoma 528 (517–550), width 171 (154–171). Prodorsal shield: 154 (143–165) in length along median line, 132 (127–143) in width at posterior margin, lateral margins entire, surface with few small circular lacunae. Setae ve present. Scapular setae si and se arranged in a transverse line. Scapular setae se 150 in length (142–158) and separated by 70 (72–78); si reduced, piliform, separated by 48 (46–57). Humeral shields absent. Setae c2 inserted dorsally on striated tegument, setae c3 lanceolate, 30 in length and 7 in width (30–33 x 7–8). Distance between prodorsal and hysteronotal shields in median line 11 (11–16). Hysteronotal shield: greatest length 374 (352–396), width at level of setae cp 125 (114–131); surface of the shield with numerous small circular lacunae, except for lobar area. Opisthosomal lobes without lateral expansions, about 2 times longer than wide, with round apices. Terminal cleft V­shaped, 71 (63–71) from anterior end to lobar apices, supranal concavity distinct. Setae h3 relatively short, curved and without terminal filament, separated by 42 (38–46). Setae ps1 inserted sub­apically, at the level of bases of h3. Length of setae: ps1 5 (5–8), h3 44 (38–44), h2 78 (65–78), ps2 63 (57–65), f2 14 (11–16), ps3 27 (22–30). Distance between dorsal setae: si–c1 76 (68–84), c1–c2 37 (35–41), c1–d1 68 (66–75), d1–d2 56 (47–56), d1–e1 107 (88–100), d2– e1 51 (39–51), e1– e2 37 (37–44), e1–h1 96 (89–105), e2–h1 60 (54–63), h1–f2 33 (32–39).

Epimerites I fused as a narrow U, their posterior ends connected with central part of epimerites II by thin sclerotised bands; setae 1a situated on these bands. Epimerites I and II with narrow sclerotised areas. Adanal shield and epimerites IVa fused into a single structure almost completely encircling genital arch. Setae 4a situated on epimerites IVa, setae g on central region of adanal shield (in some paratypes setae g off this shield, Fig. 13 ). Pregenital apodeme as narrow Y, its anterior ends fused with inner margins of coxal fields III, its posterior end almost fused with tips of epimerites IVa. Aedeagus reaches the level of anterior margins of adanal discs, 84 in length (79–87); genital arch 30 in width (29–33). Distance between ventral setae: 3a–4a 71 (68–73), 4a–g 54 (52–57), g–ps3 65 (54–65), ps3–ps3 46 (44–46). Anal discs edentate, 16 (15–16) in diameter, and distance between centers of discs 22 (18–24). Opisthoventral shields bear seta ps3 on inner margin, postero­lateral to anal discs ( Figs. 9 , 12–14 ).

Solenidion σ 1 of genu I short and pointed, seta cG of genua I, II setiform ( Fig. 16 ). Tarsus IV 35 (33–35) in length, seta f setiform, setae e and d button­like ( Fig.17 ).

Female ( Figs. 10, 11 , 15 ). (measurements of 13 paratypes). Length of idiosoma excluding terminal appendages 528–572, width 165–187. Prodorsal shield: 143–154 in length along median line, 132–143 in width at posterior margin, lateral margins entire, numerous small circular lacunae uniformly distributed. Setae ve present. Scapular setae si and se arranged in a transverse line. Setae se 155–177 in length and separated by 79–82; pair si reduced, piliform, separated by 54–58. Humeral shields absent. Setae c2 inserted dorsally on striated tegument; setae c3 lanceolate, 30–33 in length and 8–9 in width. Distance between prodorsal and anterior hysteronotal shields along median line 7–19. Anterior hysteronotal shield: greatest length 242–297, width at level of setae cp 127–143; surface with numerous small circular lacunae, two pairs of pale, lightly sclerotised areas on posterior half of this shield. Length of lobar region excluding terminal appendages 87–101, greatest width 87–101. Supranal concavity distinct, circular, on anterior margin of lobar shield. Anterior hysteronotal and lobar shields separated by thin band of soft tegument with striae. Setae h2 blade­like, without terminal filament, 57–68 in length, 8–9 in width. Setae h3 long, 73–87. Setae h1 and f2 approximately at the same transverse level. Distance between dorsal setae: si–c1 73–83, c1–c2 41–46, c1–d1 76–82, d1–d2 49–57, d1–e1 114–128, d2–e1 73–84, e1– e2 24–35, e1–h1 73–82, e2–h1 52–60, h1–f2 19–22, f2–h2 19–22.

Epimerites I fused as a narrow U, not connected with epimerites II. Epimerites I and II without sclerotised areas. Coxal fields I, II, III and IV open. Setae ps2 and ps3 setiform, set in a trapezoidal arrangement. Distance between ventral setae: 1a–3a 73–82, 3a–g 22–27, 4a–ps3 87–101, g–4a 132–144, ps2–ps3 38–44, ps2–ps2 42–46, ps3–ps3 24–28. Lobar cleft as an inverted narrow U, 60–68 in length from anterior end to lobar apices. Spermatheca and spermaducts as in Fig. 15 .

Legs I, II as in the male, legs IV extending by ambulacral disc to the level of setae h2.

Etymology

The epithet points on the first finding of a representative of the genus Dolichodectes in the Neotropical Region.

Differential diagnosis

Dolichodectes neotropicus sp. n. is similar to D. diplocercus ( Gaud & Mouchet, 1957) in having the coxal fields II opened and aedeagus reaching only the level of adanal discs. The new species can be distinguished by the shape of epimerites I, narrow U­shaped rather than Y­shaped. Males of D. neotropicus have no lateral expansions on opisthosomal lobes as in D. myrmecocichlae Mironov & Fain (2003) . Differently from the latter species, the adanal shield in D. neotropicus is an entire large plate between genital arch and anal discs. Females of D. neotropicus can be separated from other species of Dolichodectes by the length of setae h3, and by the lack of expansion on primary duct near the head of spermatheca.

Remarks

Dolichodectes neotropicus sp.n. is unique in having male genital discs well evident and set anterior to genital arch, epimerites I of both sexes are as a narrow U, and in female setae h3 are very long and strong, even longer than h2. These features are quite different from those given by Park & Atyeo (1971) in the definition of the genus Dolichodectes . However, until more species are described and the knowledge of such characteristics is fully understood, we do not consider appropriate to erect a new genus to accommodate this new species. The new species was collected from an avian family known to occur mainly in the Neotropics ( Tyrannidae ), while the previously described species were collected from birds of the Old World ( Muscicapidae and Sylviidae ) ( Gaud & Mouchet 1957) and of both regions ( Turdidae and Corvidae ) ( Gaud & Mouchet 1957; Mironov & Fain 2003). Mironov & Fain (2003) expressed doubts in the monophyly of this genus, because of the wide range of host birds.

Figures

FIGURE 8–9. Dolichodectes neotropicus n.sp. Male: dorsal (8) and ventral (9) views. Scale in µm.

FIGURE 10–11. Dolichodectes neotropicus n.sp. Female: dorsal (10) and ventral (11) views. Scale in µm.

FIGURE 12–17. Dolichodectes neotropicus n.sp.. Genital region of male holotype (12), and paratypes (13–14) showing variation on shape of plate anterior to adanal discs; female spermatheca (15); dorsal view of male legs I (16) and IV (17). Scales in µm.