Tyrannidectes falcklandicus Mironov & González-Acuña 2011, sp. n.

Tyrannidectes falcklandicus sp. n.

(Figs. 18 F–J, 19, 20)

Type material. Male holotype (ZISP 4652) 2 male and 7 female paratypes from the Austral Thrush Turdus falcklandii Quoy and Gaimard (Turdidae), CHILE: Bío Bío Region, Concepción Province, Santa Juana, 37°10'22"S 72°56'7"W, 0 3.11.2006, coll. D.A. González-Acuña.

Type depository. Holotype, 1 male and 6 female paratypes—ZISP, remaining paratypes—DGA.

Description. MALE (holotype, range for 2 paratypes in parentheses). Idiosoma, length × width, 378 (375–380) × 153 (144–155), length of hysterosoma 240 (238–240). Prodorsal shield: 126 (117–125) × 98 (95–100), lateral margins with incisions extending to bases of setae se, posterior margin slightly convex medially, antero-lateral extensions acute, surface without lacunae; scapular setae se separated by 57 (58–62) (Fig. 19 A). Setae ve absent. Humeral shields absent. Setae c2, cp situated on striated tegument. Subhumeral setae c3 lanceolate, 23 (23–24) × 7 (7–8). Hysteronotal shield: greatest length 240 (240–245), width in anterior part 88 (86–88), anterior margin slightly concave, posterior part with small circular lacunae. Distance between prodorsal and hysteronotal shields 22 (17–22). Opisthosomal lobes approximately as long as wide at base; posterior ends of lobes roughly rounded, with very short and blunt extensions at bases of setae h2 and h3. Terminal cleft shaped as an inverted U with strongly divergent branches, 29 (28–31) in length. Supranal concavity present, ovate. Setae f2 situated anterior to bases of setae ps2. Setae h1 situated at midlevel of supranal concavity. Setae h3 spiculiform, 24 (22–24) long; setae ps2 82 (80–82) long, slightly thickened in basal part; setae ps1 minute, filiform, about 5 long, situated near margin of terminal cleft, approximately at level of setae p2. Distance between bases of dorsal setae: c2:d2 93 (93–97), d2:e2 80 (80–82), e2:h3 60 (57–60), d1:d2 36 (32–36), e1:e2 26 (24–26), h1:ps2 29 (20–28), h2:h2 60 (55–60), h3:h3 42 (38–42), ps2:ps2 75 (70–75).

Epimerites I fused into a narrow U, fused part without lateral extensions (Fig. 19 B). Coxal fields I, II without extensive sclerotized areas. Rudimentary sclerites rEpIIa absent. Coxal fields I–III open. Coxal fields IV without sclerotized areas. Epimerites IVa absent. Genital arch of moderate size, with strongly divergent branches, 25 (24– 25) × 36 (35–36); posterior margin of basal sclerite semicircular; aedeagus sword-shaped, 73 (73–74) long, scarcely extending to anterior end of anal opening; genital papillae not connected by bases. Genital and adanal shields absent. Anal suckers 13 (13–15) in diameter, corolla smooth. Opisthoventral shields wide, occupying lateral parts of opisthosoma and extending to bases of setae ps2; inner margins of these shields with acute angular extension at level of anterior end of terminal cleft; setae ps3 situated at level of posterior margins of anal suckers. Distance between ventral setae: 3b:3a 10 (10–13), 3a:4a 36 (36–39), 4a:g 40 (38–40), g:ps3 55 (53–55), ps3:ps3 62 (54–60), ps3:h3 33 (30–33).

Femora I, II with narrow ventral crests, other segments of legs I, II without processes. Solenidion σ 1 of genu I 13 (12–13) long, situated at midlevel of segment; genual setae cG I, II and mG I, II filiform (Figs. 18 F, G). Seta d of tarsus II subequal to corresponding seta f, setae d of tarsus III shorter than corresponding seta f. Tarsus IV 28 (28– 29) long, without apical process; seta d situated in basal half of segment, solenidion φ of tibia IV extending to midlevel of ambulacral disc (Fig. 18 H).

FEMALE (6 paratypes). Idiosoma, length × width, 513–555 × 170–190, length of hysterosoma 352–390. Prodorsal shield: 133–144 × 118–130, lateral margins with deep incisions around bases of setae se, median part of posterior margin strongly convex, antero-lateral extensions acute, surface without lacunae; scapular setae se separated by 73–82 (Fig. 20 A). Setae ve absent. Setae cp, c2 situated on soft tegument. Setae c3 lanceolate, 24–25 × 7.5–9. Distance between prodorsal and hysteronotal shields 25–35. Anterior and lobar parts of hysteronotal shield completely separated (Fig. 20 B). Anterior hysteronotal shield enlarged anteriorly, anterior margin slightly concave, greatest length 272–285, width at anterior margin 120–130, posterior half with numerous circular lacunae up to 5 in diameter. Length of lobar region 88–100, greatest width 78–93; lobar shield split longitudinally into two pieces by narrow median band of soft tegument; each piece of lobar shield bearing 1–3 small circular lacunae; supranal concavity indistinct. Setae h2 closer to lobar apices than to anterior margin of lobar shield. Terminal cleft as a narrow V, extending slightly beyond level of setae h2, 62–71 long, width at level of lobar apices 12–22. Setae h1 on lobar shield, distant from anterior margins; setae h1 and f 2 in trapezoid arrangement. Setae h2 with spindle-like enlargement in basal part and with filiform apical part, total length 90–100, greatest width 8–9. Setae ps1 near inner margins of opisthosomal lobes. Setae h3 9–11 long, about 1/8th the length of terminal appendages. Distance between dorsal setae: c2:d2 122–126, d2:e2 106–122, e2:h2 88–104, h2:h3 28–32, d1:d2 36–44, e1:e2 37–44, h1:h2 33–40, h2:ps1 9–15, h1:h1 31–33, h2:h2 65–71.

Epimerites I fused into a narrow U; fused part without lateral extensions (Fig. 20 B). Coxal fields I without sclerotized areas, lateral parts of coxal fields II with large sclerotized areas. Epimerites IVa absent. Translobar apodemes of opisthosomal lobes present, narrow, not fused to each other anterior to terminal cleft. Epigynum with short extension on lateral margins, greatest width 62–73; apodemes of oviporus separated from epimerites IIIa. Pseudanal setae ps2, ps3 modified into suckers, arranged in transverse rectangle and situated approximately at midlevel of anal opening, distance between setae: ps2:ps2 31–42, ps3:ps3 30–38, ps2:ps3 7–12. Primary spermaduct with small ampuliform enlargement near head of spermatheca; secondary spermaducts 18–20 long, approximately twice as long as enlargement of primary spermaduct (Fig. 18 J).

Femur I without crest, femur II with narrow ventral crest, other segments of these legs without processes. Solenidion σ 1 of genu I 15–18 long, situated at midlevel of segment. Genual setae cG I, II and mG I, II filiform. Seta d of tarsus II subequal to corresponding seta f, setae d of tarsi III, IV shorter than corresponding setae f. Genu IV dorsally inflated, with low longitudinal dorsal crest (Fig. 18 I), genu III without dorsal crest.

Differential diagnosis. Among the three previously known species of the fissuratus species group, Tyrannidectes falcklandicus sp. n. is most close to T. amaurochalinus (Hernandes and Valim, 2006) described from Turdus amaurochalinus Cabanis in Brazil by having the dorsal shields without a median groove and scapular setae se, si arranged in a transverse row. Tyrannidectes falcklandicus differs from that species by the following features. In both sexes, the prodorsal shield has deep lateral incisions and its surface is devoid of any pattern; in males, lateral incisions of prodorsal shield extend to bases of setae se, epimerites IVa and rudimentary sclerites rEpIIa are absent; in females, lateral incisions of prodorsal shield encircle bases of setae se, the lobar shield is split longitudinally into two pieces, and the supranal concavity is indistinct. In both sexes of T. amaurochalinus, the prodorsal shield has no lateral incisions, both the prodorsal and hysteronotal shields are entirely covered with numerous circular lacunae; in males, epimerites IVa and rudimentary sclerites rEpIIa are present; in females, the lobar shield is entire, and the supranal concavity is clearly visible.

Etymology. The specific epithet derives from the specific name of the type host.