Picalgoides arbenzi Constantinescu

Constantinescu, Ioana Cristina, Chişamera, Gabriel, Mukhim, D. Khlur B. & Adam, Costică, 2014, Two new species of feather mites (Acarina: Psoroptidia) from the Great Barbet, Psilopogon virens (Piciformes: Megalaimidae), Zootaxa 3893 (1), pp. 127-142 : 133-140

Picalgoides arbenzi Constantinescu sp. nov.

( Figs. 5–10 )

Description. MALE ( Fig. 5 , Fig. 6 ; Fig. 7 A–D, ranges for 3 paratypes). Idiosoma 355 long (330–355), 230 wide (270–295); length of hysterosoma 240 (230–245). Prodorsal shield: length along midline 100 (100–105), width at posterior margin 100 (92–100), posterior margin straight, longitudinal crests divergent posteriorly and extend almost to posterior margin of the shield. Setae si and se on striated tegument, setae se separated by 90 (84–90). Length of hysterosoma 240 (230–245). Hysteronotal shield with its anterior angles rounded, length from anterior margin to bases of setae h3 225 (210–230), width at anterior margin 145 (135–145). Setae d2 slightly posterior to level of setae d1, setae e1 slightly posterior to level of hysteronotal gland openings gl. Supranal concavity present. Postero-lateral angles of opisthosoma pronounced, bearing setae f2. Opisthosomal lobes short, with reduced anterior and posterior incision of lobe, lateral lobar digit bearing setae ps2 short, terminal lobar digit bearing setae h3 short triangular, ledge of terminal cleft bearing setae ps1 well developed, distal margin of lobe between bases of setae h3 and ps1 concave ( Fig. 5 ). Terminal cleft like as inverted V. Terminal lamellae occupying lobar apices between bases of setae h3 and ps1 well developed, with free margin widely rounded. Measurements of opisthosomal lobes: length of anterior part of terminal cleft 24 (20–24), total length of terminal cleft 28 (26–28), length of posterior incision of lobe 20 (19–20), length of terminal lamellae 8 (8–10). Distance between idiosomal setae: c2–d2 74 (64–74), d2– e2 66 (64–74), e2–h2 64 (54–64), h2–h3 36 (32–36), f2–f2 105 (92–105), h3–h3 62 (52–62), ps1–ps1 26 (24–26), ps2–ps2 82 (72–84).

Epimerites I fused as a V, with 1 pair of short extensions at basis, epimerites II connected to epimerites III, coxal fields II closed, coxal fields III opened. Epimerites IV with large, sclerotized areas along outer and inner margins and at base of trochanters IV. Genital apparatus well developed, genital arch length 24 (24–26), width 23 (20–24), length of aedeagus 38 (30–46) ( Fig. 6 ). Paragenital apodemes fused like an inverted U, their posterior ends enlarged and extended to mid-level of trochanters IV. Setae 4a at level of genital apparatus base, setae g slightly posterior to this level. Adanal apodemes fused at anterior ends into large arch encircling anal field, their inner margin with two rounded sclerotized areas. Diameter of anal suckers 21 (18–21). Distance between ventral setae: 3a–4b 54 (46–54), 4a–g 32 (28–34), g–ps3 76 (70–78).

Tibiae I and II with pair of well-developed acute ventral spines ( Fig. 7 A, B). Tibia III with long paraxial spur 16 (14–16) at base of solenidion φ, and with poorly developed antiaxial spine ( Fig. 7 C). Tarsus IV 17 (14–17) long, with finger-like and claw-like apical processes, seta d barrel-shaped, with cap, situated between apical processes, setae e strongly reduced, situated on blunt apex of finger-like process ( Fig. 7 D).

FEMALE ( Fig. 8 , Fig. 9 ; Fig. 10 A–D, ranges for 4 paratypes) Idiosoma 300–315 long, 185–200 wide, length of hysterosoma 200–215. Prodorsal shield: length along midline 100–105, width 92–100, general form as male except for posterior margin that has acute extension in median part and longitudinal crests reaching only to midlevel of this shield. Setae si and se on striated tegument, setae se separated by 86–88. Length of hysterosoma 200–215. Hysteronotal shield with anterior margin concave, posterior margin convex, lateral margins at level of trochanters IV concave, anterior angles rounded, posterior angles acute, greatest length 125–135, width at anterior margin 80–84, width at posterior margin 92–96 ( Fig. 8 ). Setae cp three times longer than setae c3. Setae d1 and d2 at same transverse level, setae e1 at level of openings gl, setae d2 on lateral margins of hysteronotal shield, setae e2 near posterior angles of this shield. Distance between dorsal setae: c2–d2 64–74, d2– e2 73–78, e2–h2 54–58, d2–d2 78–84, e2– e2 82–90, h2–h2 80–90, h3–h3 60–66.

Epimerites I fused into a narrow U-shape, with pair of short posterior extensions ( Fig. 9 ). Epigynum semiovate, 46–52 long, 62–76 wide, lateral margins with acute extensions directed towards inner tips of epimerites III. Setae g situated at short distance from tips of epigynum. Setae h2 and h3 long, their bases conical, setae ps1, ps2 and f2 minute, 8–12 in length. Legs I and II as in male, setae d of tarsi III and IV very long, length of tarsi III 38 –41, length of tarsi IV 40 –45.

Type Material. Male holotype (ANA310), 3 male (ANA312, ANA313, ANA314) and 4 female paratypes (ANA311, ANA315, ANA316, ANA317) from Psilopogon virens (Boddaert) ( Piciformes : Megalaimidae ) [large feathers of the tail], INDIA: Meghalaya, Jaintia Hills, Shnongrim village, 25°21'12.36"N, 92°31'3.06"E; 1151 m alt; subtropical forest, 25 January 2014, coll. D.K.B. Mukhim.

Etymology. This species is named in honor of speleologist Thomas Arbenz (Matzendorf, Switzerland), one of the main organizers of the expeditions “Caving in the Abode of the Clouds - Meghalaya, India ”, for his support of our first studies on ectoparasites of birds from Jaintia Hills (Meghalaya, Northeastern India).

Differential diagnosis. Picalgoides arbenzi sp. nov. is closest to P. capitonis Černý, 1974 from Capito niger (Müller) ( Piciformes : Capitonidae ). Males of both species have epimerites I fused as a V, with a pair of short extensions at the basis, the opisthosomal lobes are short, with reduced anterior and posterior incisions, the lateral and the terminal lobar digits are short, the terminal lamellae on the inner and outer margins of the terminal lobar digit is well developed, the paragenital apodemes are fused like an inverted U, tibia III has a long paraxial spur at the base of solenidion φ, and a poorly developed antaxial spine. Picalgoides arbenzi sp. nov. can be readily differentiated from P. capitonis by the following features of males: the adanal apodemes are fused at the anterior ends into a large arch encircling the anal field and the terminal cleft is like an inverted V. In males of P. capitonis the adanal apodemes are separated and the terminal cleft is like an inverted U. In females of both species, epimerites I are fused into a narrow U with a pair of the short posterior extensions, the hysteronotal shield has the anterior and lateral margins concave, the posterior margin of this shield is convex and the anterior angles rounded, setae g are situated at a short distance from the tips of epigynum, and, setae d2 are situated on the hysteronotal shield. Picalgoides arbenzi sp. nov. can be readily differentiated from P. capitonis by the following female features: the hysteronotal shield has acute posterior angles, and setae d2 are on the lateral margins of the hysteronotal shield. In females of P. c ap i t o ni s, the hysteronotal shield has the posterior angles rounded, and setae d2 are situated at a short distance from the lateral margins of the hysteronotal shield.

Figures

FIGURE 5. Picalgoides arbenzi sp. nov., male idiosoma, dorsal view. Abbreviations: ld, lateral lobar digit; pa, postero-lateral angle of opisthosoma; td, terminal lobar digit.

FIGURE 6. Picalgoides arbenzi sp. nov., male idiosoma, ventral view.

FIGURE 7. Picalgoides arbenzi sp. nov., male legs, dorsal view. A—leg I, B—leg II, C—tibia and tarsus of leg III, D—tibia and tarsus of leg IV.

FIGURE 8. Picalgoides arbenzi sp. nov., female idiosoma, dorsal view.

FIGURE 9. Picalgoides arbenzi sp. nov., female idiosoma, ventral view.

FIGURE 10. Picalgoides arbenzi sp. nov., female legs, dorsal view. A—leg I, B—leg II, C—leg III, D—leg IV.