Gymnalloptes latihumeralis, Hernandes, Fabio A. & Mironov, Sergey V., 2015

Hernandes, Fabio A. & Mironov, Sergey V., 2015, The feather mites of the hoatzin Opisthocomus hoazin (Müller) (Aves: Opisthocomiformes), with the description of two new genera and six new species (Acari: Analgoidea, Pterolichoidea), Zootaxa 4034 (3), pp. 401-444 : 409-415

Gymnalloptes latihumeralis sp. nov.

( Figs. 6–10 )

Type material. Male holotype (DZUNESP-RC #3120) and 1 male paratype from Opisthocomus hoazin (Müller, 1776) (Opisthocomiformes: Opisthocomidae ), BRAZIL, Pará State, Fazenda Fartura, 09°40'S / 50°23'W, Santana do Araguaia, 0 8 September 2013, D.V. Boas-Filho coll. (#1112); other paratypes: 1 male and 1 female, same data (#1110); 2 females and 1 nymph, same host, BRAZIL, Rondônia State, Machadinho d’Oeste 08°56′48′′S / 61°59′54′′W, 0 8 October 2014 (#MC153), F. Schunck & V.Q. Piacentini colls.

Depository. Holotype, 1 male, 3 female and 1 nymphal paratypes at DZUNESP-RC; 1 male paratype at ZISP.

Description. MALE (holotype, values for 1 paratype in parentheses). Gnathosoma modified: subcapitulum strongly enlarged basally, with convex lateral margins. Idiosoma, length × width, 322 × 197 (318 × 185), length of hysterosoma 187 (199). Propodosoma enlarged in anterior part, its greatest width at bases of trochanters II. Prodorsal shield: anterior part roughly rectangular, posterior part with rectangular lateral extensions, with pair of longitudinal lateral ridges slightly divergent posteriorly, posterior margin slightly concave, lateral and posterior borders of the shield poorly distinct, greatest length 84 (79), width in posterior part 44 (39). Setae se situated on soft tegument near postero-lateral angles of prodorsal shield, separated by 91 (89). Scapular shields narrow, without suprategumental extensions. Humeral shields narrow, their posterior ends fused with metapodosomal shields. Hysteronotal shield represented by two pieces: anterior piece shaped as equilateral triangle directed backward by one of apices, and posterior piece represented by a narrow median band stretching from posterior margins of opisthosomal lobes to midlevel between trochanters III and IV; anterior end of this band rounded.

Length of anterior piece 78 (80), greatest width 91 (94). Length of posterior piece from anterior tip to level of bases of setae h3 [sclerotized posterior margins of opisthosomal lobes] 78 (87). Supranal concavity present, poorly distinct. Median hysteronotal setae c1, d1, e1, and h1 absent. Setae c2, d2, e2 situated on soft tegument. Opisthosomal lobes small, represented by a pair of bluntly rounded extensions not longer than wide at base, separated by narrow almost slit-like terminal cleft, distal halves of lobes bearing complex of lobar setae poorly sclerotized (membranous). Terminal cleft short, about 10 long, lateral margins almost touching. Distance between dorsal setae: c2: d2 72 (69), d2: e2 73 (86), c2: c2 119 (119), d2: d2 58 (57), e2: e2 21 (22), h2: h2 22 (23), h3: h3 16 (15).

Epimerites I fused into a Y, sternum about 1/4 of length of epimerites. Area between free parts of epimerites I and anterior parts of coxal fields II sclerotized. Epimerites IIIa long, extending to level of setae cp, widely separated from each other, their anterior ends small sclerotized plates bearing setae 4b. Epimerites IVa very long, their anterior ends continuous with paragenital apodemes flanking genital apparatus laterally and fused with epimerites IIIa. Genital apparatus elongate, 38 (36) long, 21 (22) wide at base, its base approximately at midlevel of trochanters III. Setae g situated posterior to level of setae 3a. Adanal suckers circular, 11 (8) in diameter, corolla with numerous denticles. Distance between ventral setae: 4b: 4b 40 (40), 4b: 3a 20 (21), 4b: g 29 (26), g: ps3 66 (71), ps3: ps1 57 (55).

Legs I noticeably larger than legs II. Tibiae of legs I, II with a pair of small apico-ventral spines and with apico-dorsal spine at base of solenidia φ. Tarsi I, II with a pair of apico-dorsal spines, tarsus I with ventral claw-like extension at base of ambulacral stalk. Ambulacral discs of tarsi I, II circular, subequal; discs of tarsi III, IV also circular, approximately 1/5th the diameter of those on tarsi I, II. Ambulacral stalk of tarsus I slightly thicker and longer than that on tarsus II. Setae vF of femora I with membranous extension in basal part, setae vF of femora II filiform. Length of posterior legs, excluding ambulacrum: III 168 (167), IV 227 (215). Tarsus III 47 (50) long, ambulacral stalk with 2 ventral spines ( Fig. 8 D). Tarsus IV conical, with thick and rounded apical extension, length including extension 53 (52), setae e absent ( Fig. 8 F).

FEMALE (range for 3 paratypes). Idiosoma, length × width, 341–359 × 149–159, length of hysterosoma 237– 265. Prodorsal shield: roughly rectangular, anterior margin deeply concave, posterior margin straight, posterior angles with minute oblique extensions, 61–66 long, 25–29 wide. Distance between scapular setae se 71–75. Scapular shields narrow, inner margin with narrow suprategumental extension. Hysteronotal shield shaped as small longitudinally elongate plate, attenuate posteriorly, with rounded anterior and posterior ends, length along midline 64–68, greatest width 19–22. Posterior margin of opisthosoma slightly convex between bases of setae h3. Copulatory opening situated terminally on small conical extension. Distance between dorsal setae: c2: d2 79–91, d2: e2 88 –101, e2: h 3 30–43, c2: c2 113–133, d2: d2 66–82, e2: e2 64 –71, h2: h2 58–61, h3: h3 38–50.

Epimerites I fused into a Y, sternum about ½ of length of these epimerites. Epimerites IIIa short, directed transversely. Epimerites IVa present, short. Bases of trochanters III, IV not flanked by sclerotized bands. Epigynum bow-shaped, thickened in medial part, bearing bases of setae 4b on posterior margin, 9–13 long, 42–45 wide. Apodemes of oviporus with long and wide posterior extensions, reaching midlevel of trochanters IV. Setae g situated posterior to level of coxal setae 3a. Distance between ventral setae: 4b: g 23–30, g: 4a 46–52.

Legs I, II smaller than those in male. Tarsi I, II with small apico dorsal extension. Femur I with rounded lateroventral extension. Tibiae I–IV with a pair of small ventral spines. Seta sR III filiform, shorter than corresponding femoragenu. Seta kT of tibia III shorter than this segment. Tarsus III 59 –61 long, tarsus IV 69 –72 long. Ambulacral discs of tarsi I, II circular, subequal; discs of tarsi III, IV circular or slightly ovate, about half the width of those of tarsi I, II. Ambulacral stalks of tarsi III, IV about 1.5 times longer than corresponding ambulacral discs. Setae d of tarsi III, IV filiform, much shorter than corresponding segments.

Differential diagnosis. The new species Gymnalloptes latihumeralis sp. n. is close to G. lacrimosus described above by the absence of four pairs of median hysteronotal setae (c1, d1, e1, and h1) in both sexes, by having the hysteronotal shield split into anterior and posterior pieces in males, and by the presence of a small hysteronotal shield in females. Males of G. latihumeralis differ from those of G. lacrimosus by a number of features: the propodosoma is hypertrophied with the largest part at the level of trochanters II, the subcapitulum is strongly enlarged with convex lateral margins, legs I are noticeably longer and thicker than legs II, the prodorsal shield is represented by a wide trapezium-like plate, the anterior piece of the hysteronotal shield is roughly triangular, opisthosomal lobes are short and rounded posteriorly, the terminal cleft has almost touching lateral margins, the paragenital apodemes connecting the inner ends of epimerites IIIa and anterior ends of epimerites IVa are present, tarsi I, II have two dorso-apical spines, tibiae I, II have acute dorso-apical extensions at bases of solenidia φ, tarsus IV is half as long as corresponding tibia and with bluntly-rounded apical extension. In females of G. latihumeralis , the anterior margin of prodorsal shield is deeply concave, the hysteronotal shield is shaped as a small longitudinal sclerite narrowed posteriorly, the scapular shields have suprategumental hyaline extension along inner margin, the epigynum is represented by a slightly curved sclerite with very thin tips.

In males of G. l a cr i m o s u s, the propodosoma is normal, gradually narrowed anteriorly, the subcapitulum is nearly rectangular, legs I and II are subequal, the prodorsal shield is represented by a rectangular plate, the anterior piece of the hysteronotal shield is shaped as an inverted tear-drop, the opisthosomal lobes are 2.5–3 times longer than wide and with tongue-shaped apices, the terminal cleft is rectangular (9–12 in width), the paragenital apodemes connecting epimerites IIIa and epimerites IVa are absent, tarsi I, II are rounded apically, tibiae I, II do not have dorso-apical extensions, tarsus IV is subequal to tibia IV and with bidentate apical extension. In females of G. lacrimosus , the anterior margin of prodorsal shield is straight, the hysteronotal shield is shaped as an inverted teardrop, the scapular shields do not have suprategumental hyaline extension on the inner margin, the epigynum is represented by an almost semicircular bow.

Etymology. The specific epithet refers to the strong, bulky appearance of males of this mite, noticeably enlarged in the anterior part of the body.

Figures

FIGURE 6. Gymnalloptes latihumeralis sp. n., male. A—dorsal view, B—ventral view.

FIGURE 7. Gymnalloptes latihumeralis sp. n., male. A—opisthosoma, dorsal, B—genital apparatus, C—opisthosoma, ventral.

FIGURE 8. Gymnalloptes latihumeralis sp. n., male. A—leg I, dorsal, B—tarsus I, ventral, C—leg II, dorsal, D—tarsus III, ventral, E—leg III, dorsal, F—leg IV, dorsal.

FIGURE 9. Gymnalloptes latihumeralis sp. n., female. A—dorsal view, B—ventral view.

FIGURE 10. Gymnalloptes latihumeralis sp. n., female. A – D—legs I – IV, dorsal, E—spermatheca.