Trouessartia insularis, Hernandes & Licarião, 2025

Trouessartia insularis sp. nov.

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( Figs. 6–10 View FIGURE 6 View FIGURE 7 View FIGURE 8 View FIGURE 9 View FIGURE 10 )

Type material. Holotype male, paratypes 8 males, 6 females ex Vireo gracilirostris Sharpe, 1890 ( Passeriformes : Vireonidae ), BRAZIL, Pernambuco, Fernando de Noronha, Sancho Beach , -3.855044, -32.441128, 17 August 2023, coll. G. Sobral, #D168342; other paratypes: 2 males, 4 females, same data, #D168330, coll. C. Licarião; 6 males, 2 females, same data, #D168331, coll. C. Licarião; 1 male, same data, #D168329, coll. G. Sobral; 1 male, 1 female, same data, #D168340, coll. C. Licarião. GoogleMaps

Description. MALE ( holotype, range for 6 paratypes in parentheses) ( Figures 6 View FIGURE 6 , 8A–D View FIGURE 8 , 9A View FIGURE 9 , 10A, C–E View FIGURE 10 ). Length of idiosoma from anterior end to bases of setae h3 481 (464–496), greatest width of idiosoma at level of setae d1 212 (209–224). Length of hysterosoma from sejugal furrow to bases of setae h3 301 (286–300). Prodorsal shield: length along midline 137 (132–142), greatest width posterior to scapular setae 148 (139–155), lateral margins with two concavities at level of scapular setae, posterior part not fused with scapular shields, anterolateral extensions acute, not extending to bases of epimerites Ia between legs I and II, posterior angles acute, surface with faint reticulate pattern ( Figures 6A View FIGURE 6 , 10C View FIGURE 10 ). Vertical setae ve represented by alveoli. Internal scapular setae si thin setiform, 27 (25–34) long, separated by 55 (54–64); external scapular setae se 153 (133–165) long, separated by 95 (91–102). Humeral shield with setae c2 thin, setiform, 63 (51–59) long. Setae c3 lanceolate, without subapical tooth, 23 (14–23) long. Prohysteronotal and lobar shields completely split from each other. Prohysteronotal shield: length 188 (180–196), greatest width at level of humeral shields 154 (142–159), lateral margins roughly sinuous, with a few indentations and protrusions at level of trochanters III, dorsal hysterosomal apertures (DHA) and sclerotized parches absent, surface with faint reticulate pattern, posterolateral margins with U-shaped darker area from levels of setae d2 to e2. Dorsal setae d1, d2 present, minute. Setae h1 inserted dorsally between setae ps2 and h2. Length of lobar shield excluding lamellae 94 (93–99). Opisthosoma attenuate posteriorly; opisthosomal lobes fused to each other along midline forming a sclerotized median septum, with only apical parts of lobes posterior to setae h2 separated by narrow parallel-sided terminal cleft, length of cleft from anterior end to apices of lamellae 49 (42–58), width around level of setae ps1 10 (6–10). Lamellae semicircular, margins smooth, length from bases of setae h3 to lamellar apices 33 (23–30), width of each lamella at level of setae h3 33 (31–35). Setae h2 284 (257–298) long, setae h3 140 (126–175) long. Distance between levels of dorsal setae and setal pairs: c2:d2 70 (66–73), d1:d2 48 (37–56), e1: e2 46 (37–48), e2:h2 81 (77–86), h2:h3 24 (24–26), h2:h2 44 (42–48), h3:h3 36 (33–41).

Epimerites I free. Rudimentary sclerites rEpIIa present, small, shaped roughly as an inverted teardrop, with a small lacuna inside. Humeral shield ventrally fused with epimerites III. Genital apparatus situated between levels of trochanters III and IV, length 50 (48–53), greatest width 28 (23–28) ( Figures 6B View FIGURE 6 , 10D–E View FIGURE 10 ), aedeagus short, distal end thin, hook-like. Epiandrum present, small, roughly oval-shaped, situated at anterior end of genital apparatus. Postgenital plaque present, semicircular; genital shield absent; setae g thin, piliform, with bases not enlarged and not touching each other. Epimerites IVa present, their anterior ends not reaching the level of setae g. Apophyses of adanal apodemes shaped as small triangular extensions situated slightly anterior to the translobar apodeme. Translobar apodeme present. Setae ps3 on small triangular adanal shields situated anterior to adanal suckers.Adanal suckers 18 (16–20) in diameter, distance between centers of discs 27 (26–30). Setae 4b situated anterior to level of setae 3a, setae g slightly posterior to level of 4a. Distance between ventral setae: 4b:3a 12 (10–14), 4b:g 85 (72–100), g:ps3 46 (45–49), ps3:ps3 38 (34–41).

Legs IV with ambulacral disc extending to level of setae h3. Setae sR of trochanters III lanceolate, with acute apex, 17 (15–17) long. Modified setae d of tarsus IV barrel-shaped, with discoid cap, situated in distal half of the segment; modified setae e hemispheroid, without cap, situated apically, setae d and e inserted almost contiguously near tarsal apex ( Figure 8D View FIGURE 8 ). Length of solenidia: σ of genu I 44 (45–55), σ of genu II 14 (10–15), σ of genu III 32 (27–32), φ of tibia I 74 (62–74), φ of tibia II 82 (75–82), φ of tibia III 63 (58–66), φ of tibia IV 40 (40–47), ω1 of tarsus I 22 (20–23), ω3 of tarsus I 28 (31–35), ω1 of tarsus II 24 (23–28).

FEMALE (range for 5 paratypes) ( Figures 7 View FIGURE 7 , 8E View FIGURE 8 , 9B–C View FIGURE 9 , 10B, F, G View FIGURE 10 ). Length of idiosoma from anterior end of prodorsal shield to sclerotized tips of lobes, excluding lamellar lobar processes 486–517, greatest width 214–233. Length of hysterosoma from sejugal furrow to apices of lamellar lobar processes 347–376. Prodorsal shield: shape and surface as in male, 136–153 in length, greatest width 146–169 ( Figure 7A View FIGURE 7 ). Vertical setae ve represented by alveoli. Setae si thin setiform, 24–39 long, separated by 56–68; setae se 147–177 long, separated by 100–110. Humeral shields with setae c2 thin setiform, 53–56 long. Setae c3 narrowly lanceolate, without subapical tooth, 17–24 in length. Hysteronotal shield: length from anterior margin to bases of setae h3 293–316, width at largest part at the level of setae d1 148–173, lateral margins sinuous, with two irregular concavities at level of trochanters III, DHA and sclerotized patches absent, surface with faint reticulation on anterior half, and slit-like longitudinal lacunae between levels of setae e1 and supranal concavity, borders darker than remaining surface. Dorsal setae d1, d2 present, minute. Setae h1 thin spiculiform, 23–29 long, situated anteromesal to bases of setae h2. Distance between bases of h1 and lateral margins of hysterosoma 21–24. Width of opisthosoma at level of setae h2 104–117. Setae ps1 positioned dorsally on opisthosomal lobes, much closer to bases of h3 than to h2, equidistant from outer and inner margins of lobe. Distance from bases of setae h3 to membranous apices of lobes 55–60. Setae f2 present, minute, placed posterolateral to ps2. Setae h2 245–270 long, setae h3 215–259. Supranal concavity open posteriorly into terminal cleft. Length of terminal cleft including supranal concavity 153–168, width of cleft at level of setae h3 39–45. Interlobar membrane narrow. External copulatory tube short finger-shaped, situated on the free margin of interlobar membrane, 11–13 long. Primary spermaduct guide very short, half as long as supranal concavity, not reaching the level of setae h1. Spermatheca as in Figure 9C View FIGURE 9 , secondary spermaducts 17–28 long. Distance between levels of dorsal setae and setal pairs: c2:d2 74–85, d1:d2 41–49, d2:e2 92–100, e1: e2 32–40, e2:h2 67–75, h1:h1 47–55, h1:h2 15–20, h2:h2 83–94, h3:h3 61–69.

Epimerites I free. Epigynum 47–55 in length, 101–117 in width ( Figure 9B View FIGURE 9 ). Epimerites IVa present. Adanal sclerites absent. Setae ps3 situated at posterior level of anal opening. Setae sR of trochanters III lanceolate, with acute apex, 12–18 long. Legs IV with ambulacral disc extending to level of setae ps1. Length of solenidia: σ of genu I 47–61, σ of genu II 12–14, σ of genu III 28–32, φ of tibia I 66–73, φ of tibia II 70–82, φ of tibia III 55–63, φ of tibia IV 26–32, ω1 of tarsus I 20–23, ω3 of tarsus I 29–35, ω1 of tarsus II 24–28.

Differential diagnosis. The new species, Trouessartia insularis sp. nov., does not fit to any of the 11 species groups (Mironov 2022). Most of all, the new species resembles T. savanae Hernandes, 2014 in having setae si and c2 very thin (=piliform), setae c3 and sRIII lanceolate with acute apex, and the lateral margins of hysteronotal shield without any distinct dark patch at the level of trochanters III. In females of both species, setae h1 are thin lanceolate, the copulatory tube is short; and in males setae g are short filiform, and seta d of tarsus IV are positioned distally in the segment, close to seta e. The new species, T. insularis sp. nov., can be separated from T. savanae based on the following features: in males, the epiandrum is relatively smaller, roundish and placed near the parameres of the genital apparatus ( vs. larger, square-shaped and distinctly anterior from the parameres in T. savanae ); the postgenital plaque is present ( vs. absent); genital setae g are distinctly separated from each other ( vs. touching at bases), and the posterior part of the basal sclerite of genital apparatus is strongly sclerotized ( vs. unsclerotized). In females of T. insularis sp. nov., the opisthosomal lacunae between the levels of setae e1 and e2 are narrow slit-like ( vs. oval to rounded in T. savanae ), the reticulate pattern of ornamentation is present on the prodorsal shield and in the anterior half of the hysteronotal shield ( vs. reticulate ornamentation absent).

Remarks. This is the first description of Trouessartia species from a host of the Vireonidae (see Hernandes 2022; Mironov 2022). Silva et al. (2015) reported an undetermined species from another vireonid, Hylophilus amaurocephalus (Nordmann, 1835) .

Etymology. The specific name points out that the type locality of this species is an island (Fernando de Noronha).