Dubininia psittacina ( Trouessart, 1885 )

Mironov, Sergey V., Ehrnsberger, Rainer & Dabert, Jacek, 2017, Feather mites of the genera Dubininia and Cacatualges (Acari: Xolalgidae) associated with parrots (Aves: Psittaciformes) of the Old World, Zootaxa 4272 (4), pp. 451-490 : 467-470

Dubininia psittacina ( Trouessart, 1885)

( Figs. 11 , 12 A–D, 13)

Protalges psittacinus Trouessart 1885: 57 .

Dubininia psittacina, Gaud 1980: 12 , fig. 1d; Gaud and Atyeo 1981a: 69.

Material examined. 3 males and 3 females ( AMNH 623843 , YSU 2547) from Strigops harboptilus Gray GR ( Strigopidae ), New Zealand , South Island , Otago, circa 1980, coll. unknown.

Description. Male (range for 3 specimens). Idiosoma, length × width, 380–390 × 260–270, length of hysterosoma 240–250. Prodorsal shield narrowly oval, without posterolateral extensions, with a pair of median ridges, with rounded posterior end extending beyond level of scapular setae se, length along midline 90–96, greatest width 40–42 ( Fig. 11 A). Scapular setae se, si situated on small teardrop-like posterolateral fragments of prodorsal shield, bases of setae se separated by 54–56. Hysteronotal shield fused laterally with humeral shields, anterior margin slightly convex, greatest length from anterior margin to level of setae h3 240–245, surface with a pair of longitudinally striated patches mesal to area of humeral shields. Setae c2 situated on anterior margins of humeral shields. Lateral margins of opisthosoma converging posteriorly and slightly concave, width of opisthosoma at level of setae f2 115–120. Opisthosomal lobes long, narrowing terminally; terminal cleft large semi-oval; interlobar septa not extending to level of setae e2; length of cleft from anterior end to level of setae h3 62–67, length of cleft including septa 95–100. Interlobar membrane well-developed; incision in this membrane triangular, with slit-like anterior end, 38–42 long; terminal extensions of interlobar membrane small, with rounded posterior margins, 12–15 long. Lateral membranes with smooth lateral margins posterior end without extension. Setae d2 not extending to lobar apices, setae e2 extending to posterior margins of terminal membranes. Setae h2, h3, f2 situated on lobar apices, bases arranged in roughly transverse row, setae ps1 situated slightly anterior to level of setae f2. Setae f2 long filiform, extending beyond level of tarsal apices IV. Setae ps2 situated on posterolateral margin of terminal extensions of interlobar membrane. Distance between dorsal setae: c2:d2 60–64, d2:e2 68–72, e2:h3 96–102, h2:h2 98–102, h3: h3 80–84, ps1:ps1 60–64, ps1:h3 6–8, h3:ps 2 10–12.

Epimerites fused as a Y, sternum about 1/2 of the total length of epimerites, area between anterior parts not sclerotized ( Fig. 11 B). Rudimentary sclerites of epimerites IIa present. Epimerites IIIa long, their sclerotized areas large, with two acute extensions. Coxal fields IV closed. Genital apparatus enlarged posteriorly 25–27 × 15–16; paragenital apodemes absent; genital shield small, poorly sclerotized, bearing setae g. Adanal shield entire, bowshaped, with tips not extending to level of adanal suckers, bearing setae ps3. Adanal suckers slightly oval, longitudinal diameter 18–20. Setae 4b situated anterior to level of setae 3a. Setae 1a represented by macrosetae extending to midlevel of terminal cleft; setae 4b short filiform, extending to level of setae g; setae 3a extending to level of lobar apices. Distance between ventral setae: 4b:g 30–32, g:ps3 48–50, ps3:h3 105–110.

Tarsus I with ventral setae la, ra filiform, setae wa and s slightly thickened basally ( Fig. 12 A). Solenidion σ1 of genu I 95 –100 long. Tarsus II with tongue-like ventral extension, seta s lanceolate at base, setae wa whip-shaped with membraneous extension in medial part ( Fig. 12 B). Ambulacral disc I normally developed, with long triangular central sclerite; ambulacral disc II much smaller, nearly one fourth the length of disc I, central sclerite triangular; ambulacral discs III and IV strongly reduced. Legs III with tarsus and distal part of tibia extending beyond lobar apices. Tibia III without spine-like apical extension, 8 5–88 in length, seta kT not extending to midlevel of tarsus III ( Figs. 11 , 12 C). Tarsus III 75 –80 long, with small spine-like apical process; setae w half as long as segment length; setae e, f situated approximately in middle of segment, e three times shorter than d. Tibia IV 56 –58 long, without dorsal ridge; tarsus IV 27–29 long, with tridentate apex ( Fig. 12 D). Length of ambulacral discs: I—25–26, II—7–8, III and IV—5–6.

Female (range for 2 specimens). Idiosoma, length × width, 370–380 × 230–240, length of hysterosoma 220– 235. Prodorsal shield pear-shaped, strongly narrowed in anterior part, without posterolateral extensions, with a pair of median ridges, median area with larger dots than in lateral areas, posterior margin bluntly rounded, extending to level of setae se, length along midline 95–100, greatest width 50–52 ( Fig. 13 A). Scapular setae se, si situated on small circular fragments of prodorsal shield, setae se separated by 73–75. Opisthosoma widely rounded. Hysteronotal shield absent. Bow-like sclerites flanking dorsally bases of trochanters III, IV. Distance between dorsal setae c2:d2 82–86, d2:e2 92–96, e2:h3 48–50, h2:h2 72–75, h3:h3 48–52. Setae c2, d 2 25–30 long, setae e2 50 –52 long, extending to level of setae h2.

Epimerites I fused into a Y with very short sternum, area between free parts of epimerites not sclerotized ( Fig. 13 B). Epigynum shaped as slightly curved sclerite, 13–15 × 42–45, tips not extending to level of genital papillae, setae 4b situated on the tips of epigynum. Apodemes of oviporus short, extending slightly beyond level of trochanters III. Epimerites IIIa, IVa small. Setae 1a short filiform, not extending to epigynum. Length of setae: 3a, g 45–47, 4b 30–35, 4a about 95–105 long. Setae g and 3a situated at same transverse level. Distance between ventral setae: 4b:g 38–40, g:4a 70–75.

Legs I, II as in male. Genual solenidion σ 1 I 52–55. Length of leg segments: tibia III 4 3–45, tarsus III 56 –59, tibia IV 56 –58, tarsus IV 72 –74. Tarsi III, IV without ventral extensions ( Fig. 13 ). Setae sR III filiform, 38–40 long; setae kT III filiform, shorter than corresponding tibiae; length of tibial solenidia: φ III, 33–35, φ IV 29–31. Setae w III, w IV, r IV thickened basally, with filiform apex; remaining setae of tarsi III, IV filiform. Ambulacral discs: I— 24–25, II—15–16, III and IV—12–13 long. Ambulacral stalks of tarsi III, IV three times longer than corresponding discs. Seta d of tarsus III equal to and seta d of tarsus IV slightly longer than corresponding segments.

Remarks. Trouessart (1885) briefly described this species from Strigops harboptilus without any illustrations. Gaud (1980) for the first time gave the drawings of male, but did not indicate whether he used a type specimen or newly collected samples. Type samples were not available for our study therefore the above description is made on the additional material from the type host and location.

Figures

FIGURE 11. Dubininia psittacina (Trouessart, 1885), male. A—dorsal view, B—ventral view.

FIGURE 12. Tibiae and tarsi of male. A – D— Dubininia psittacina (Trouessart, 1885), legs I – IV, respectively, E – H— D. africana Gaud, 1980, legs I – IV, respectively.

FIGURE 13. Dubininia psittacina (Trouessart, 1885), female. A—dorsal view, B—ventral view.