Dicrorobius alatus Mironov et Wauthy, 2005

Mironov, Sergey V. & Wauthy, Georges, 2005, Two new species of the feather mite genus Dicrurobius Mironov, 2001 (Acari: Astigmata: Pteronyssidae) from drongos (Passeriformes: Dicruridae) in Africa, Zootaxa 1103 (1103), pp. 27-39 : 28-33

Dicrorobius alatus Mironov et Wauthy sp. n. ( Figs. 1a, b, 2a–h, 3a, b)

Type material

Male holotype, 1 male and 2 female paratypes ( MRAC 180 186) ex Dicrurus atripennis Swainson, 1837 (Dicruridae) , south CAMEROON, September 1955, coll .

unknown; 9 male and 13 female paratypes, same data ( MRAC 180 184, 180 185, 180 187 –180 189, 5 slides). Holotype and all paratypes —MRAC.

Additional material

2 males and 2 females ( UGA 1793 USNM 255 624) ex Dicrurus atripennis , GABON, N’Komi , Ogouma, 2 October 1918, C.R. Aschmeier .

Description

Male (holotype). Idiosoma length from anterior margin to base of setae h2 405, width at level of humeral shields 255 (idiosomal size in 10 paratypes 395–410 x 225–255). Length of hysterosoma 255. Prodorsal shield: posterior angles almost rectangular, lateral margins without incision, posterior margin straight, length along midline 148, width at posterior margin 150, setae se separated by 120 ( Fig 1a). Setae c2 hair­like, short, situated on inner margin of humeral shields; setae c3 lanceolate, 30 x 7. Hysteronotal shield entire, anterior margin straight, anterior angles blunt, length along midline 245, greatest width at level of humeral shields 168. Distance between prodorsal and hysteronotal shields about 10. Opisthosomal lobes truncated; posterior margin of these lobes with narrow terminal membrane, which forms acute claw­shaped protrusion near outer angle of each lobe; median incision in terminal membrane as an inverted U, extending anterior to the level of setae ps1 by approximately 10. Supranal concavity extending to level of setae e2; distance from anterior end of the concavity to level of setae ps1 48. Setae f2 dorsal, anterior to base of setae ps2. Dorsal measurements: c2:d2 42, d2:e2 100, d2:gl 34, gl: e1 12–13, e2:h3 76, h2:h2 79, h3:h3 58. Setae ps1 about 30 long. Epimerites I fused as a Y, sternum about 1/3 of total length of epimerites. Transventral sclerite V­shaped, 20 along midline, 15 in width in narrowest part ( Figs. 1b, 2h); tips of epiandrium extending to base of genital apparatus; genital arch 24 x 12; aedeagus thin, directed anteriorly. Adanal shield represented by unpaired sclerite at anterior end of anal slit and a pair of small lateral sclerites bearing setae ps3 ( Fig. 2g). Diameter of anal discs 28. Ventral measurements: ps2:ps2 107, ps3:ps3 46, ps3:h3 52. Ventral membrane of tarsus I as long as segment ( Figs. 2a, b). Tarsus III 104 long, with narrow acute apex, seta w setiform, about 60 long; setae s narrowly lanceolate, 22 long, setae r slightly longer than segment ( Fig. 2 d). Tarsus IV subequal in length to tibia IV; modified seta d much larger than modified seta e ( Fig. 2e).

Female (paratype). Idiosoma length x width 525 x 255 (idiosomal size in all 15 paratypes 490–535 x 235–260). Length of hysterosoma 350. Prodorsal shield: posterior angles elongated, extending almost to setae c2; lateral margins without incision; posterior margin deeply concave; length of the shield along midline 148, greatest length 172, width of posterior part 180, setae se separated by 130. Setae c2 hair­like, short; setae c3 lanceolate, 36 x 8. Hysteronotal shield entire, pygidial fragment demarked by short lateral incisions but not completely split from the main body; anterior part of the shield between levels of trochanters III and IV with pair of large lateral extensions; median part of the shield with cell­like pattern ( Fig. 3a); total length of the shield 345, width at anterior margin 105, width at level of lateral extensions 184. Setae d2 mesal to lateral margins of hysteronotal shield. Setae ps1 anterior to level of setae h2. Dorsal measurements: c2:d2 105, d2:e2 146, d2:gl 65–68, gl: e1 12–22, e2:h3 89, h2:h2 92, h3:h3 76. Epimerites I fused as a Y, sternum short, less than 1/5 of epimerite length. Epigynium with short lateral extensions and slightly divergent posterior ends, 64 x 102 ( Fig. 3b).

Diagnosis

Differs from other species by the following combination of features: in males, the prodorsal shield with almost straight posterior margin, the distance between prodorsal and hysteronotal shields along midline is 10–15, transventral sclerite slightly longer than wide, and the incision in terminal membrane extends beyond the level of setae ps1, length of setae ps1 about 1/3–1/2 of opisthosoma width ( Figs. 1a, b, 2g, h); in females, hysteronotal shield entire (not separated into main body and pygidial fragment), anterior part of this shield with wide lateral extensions, median part of the shield with cell­like pattern ( Fig. 3a).

Etymology

From ala (wing, Latin) to point out to wing­like lateral extensions of the hysteronotal shield in females.