Hygronemobius nigrofasciatus Desutter-Grandcolas, 1993

(Figs. 19–24, Map 1)

Hygronemobius nigrofasciatus Desutter-Grandcolas, 1993: 17 . Holotype: male, FRENCH GUIANA, Cayenne. Depository: Museum National d’Histoire Naturelle, Paris (MNHN).

Hygronemobius nigrofasciatus: Pereira, Miyoshi, Martins, Fernandes, Sperber & Mesa, 2013: 1, 4, 16, 17.

Material examined. 41 males and 12 females. Brasil [Brazil], Piauí, Piracuruca, Parque Nacional de Sete Cidades, 4°5'3.48"S 41°41'58.751"W [~ 200m], 24. VI.2007, Carvalho, Albuquerque & Oliveira-Neto leg. Pitfall de invertebrados [Pitfall for invertebrates] / Campo limpo [open field]/ PTFCL7 (MPEG) . 1 female. Same data as preceding, but Pitfall de invertebrados [Pitfall for invertebrates] / Mata de galeria [galery forest]/ PTFGAL7 . 1 male. Same data as preceding, but Rede de varredura [sweep net] / Campo limpo [open field] / PTFCL7 (MPEG) . 8 males and 6 females. Same data as preceding, but Pitfall de invertebrados [Pitfall for invertebrates] / Cerrado rupestre / PTFCR7 (BOTU) . 7 males and 6 females. Same data as preceding (INPA) .

Revised diagnosis. Complementing what was mentioned by Desutter-Grandcolas (1993), this species is distinguished by the coloration of the maxillary palps and head, the shape and color of the pronotum, and the male genitalia. Regarding the maxillary palps, the last three segments are white, while the first two are spotted in brown. Our extensive series also showed that the brown coloration of the basal segments could extend up to half of the third segment (Fig. 19F). The head has a dark brown to blackish stripe that extends from the frons, across the genae and reaches the area posterior to the eyes, almost continuous with the stripe on the lateral lobe of the pronotum (Figs. 19E; 20A). Three parallel, longitudinal brown stripes mark the vertex (Fig. 19B), while the fastigium is lighter (Fig. 19E). The pronotum is wider than long, with a disc spotted in brown and with a longitudinal stripe on each lateral margin (Fig. 20A). Regarding the genitalia, the apical lobes are reduced, truncated, smaller than those of any other species in the stellatus group, and covered with small scale-like setae. The pseudepiphallic sclerite is well differentiated from the pseudepiphallic apical lobes, bearing a row of long setae that starts at the posterior portion and runs obliquely to the proximal portion of the median pseudepiphallic lobe (Fig. 23A); in lateral view, the distal margin is slightly elevated and the ectophallic fold is reduced (Fig. 23D). Females have an almost straight ovipositor (Fig. 24D), with the supra-anal and subgenital plates being light brown, almost translucent, and featuring a dark brown longitudinal median stripe (Fig. 24G). It differs from Hygronemobius stellatus Desutter-Grandcolas, 1993 and Hygronemobius nanus Desutter-Grandcolas, 1993, which have acuminated apical lobes extending beyond the posterior edge of the phallic complex, whereas, in H. nigrofasciatus, these lobes are truncated and not projected.

Redescription. Head triangular in frontal view, with eyes taller than wide, antennal orbits close to the lower portion of the eyes, and three dark longitudinal linear marks at the vertex (Fig. 19B). A continuous dark mark without reticulation extends from the upper base of the antenna, across the clypeus, gena, and labrum, till the surface posterior to the eyes (Fig. 19E). First two segments (proximal) of the maxillary palps almost identical, cylindrical, and spotted in brown; third segment as long as the two first summed, usually light brown proximally and distally white; fourth smaller than the third and entirely white; fifth also entirely white but apically truncated and longer than the previous segments (Fig. 19F). In frontal and lateral views, eyes taller than wide (Figs. 19D, E).

Thorax. Pronotum, in dorsal view, rectangular and truncated, wider than long, and slightly narrower near the head. Pronotal disc with whitish longitudinal lines flanking a dark central irregular mark with a characteristic pattern (Fig. 20A). Lateral lobes predominantly dark in most of the area, forming a linear mark contiguous with the darker surface of the head; ventral border concave medially (Fig. 20C). AS formed by three almost aligned macrochaeta. MSG formed by four setae, being a medial mesochaeta, followed by an oblique-positioned macrochaeta, another almost aligned macrochaeta, and an anteriorly positioned macrochaeta. PS formed by seven macrochaeta and four mesochaeta, extending laterally to the anterior half of the lateral lobes. LS formed by five macrochaeta (Fig. 20B). The pattern of each set of setae can be seen in Figs 20B, D. Prosternum almost concolorous, with a dark oblique anterior line and another arched posterior one. Mesosternum square-shaped, with the anterior area darker. Metasternum hexagonal, with a slightly darkened triangular spot on the anterior region (Fig. 19G).

Wings. Tegmina longer than wide, almost hyaline, with darkened spots in the anal, post-cubital, harp, and distal apex regions, starting from the cubito-anal region and radiating along the entire extension along the medial + cubito-anal vein. An+PCup veins weakly visible (Fig. 21A). All four C+Sc not connected, with a slight curvature in the first vein (Fig. 21B, white circle). Stridulatory file with 40 teeth (N = 1; Fig. 21C).

Legs. Fore tibia with two ventral-apical spurs and a well-visible tympanum on the outer surface (Figs. 22A–B); predominantly brown, with two whitish spots on each surface (Figs. 22A–B). Fore femora dark brown, with a distal ochre spot on the outer surface (Fig. 22A) and an irregular spot extending from the distal portion to the mid portion of the outer surface (Fig. 22B). Mid femora similar to the fore femora but darker, with lighter spots almost inconspicuous (Figs. 22C–D). Hind femora predominantly dark brown, proximal portion and some distal spots ochre (Figs. 22E–F). All tarsi whitish or ochre, with a brown ring on the proximal and distal portions of the basitarsi, second tarsal segments, and proximal and distal portions of the third segments (Figs. 22A–F).

Abdomen, in dorsal and ventral views, darkened in color, with wings covering up to the sixth segment (Figs. 19A–B). Six pairs of whitish spots precede the tenth tergite, with the third pair smaller than the previous ones, light brown. Abdominal sternites light brown and with darkened edges; sternites V, VI, and VII with a centered and slightly darkened spot (Fig. 19B). Supra-anal plate lighter than the preceding segments, with a convex posterior border (Fig. 22G). Subgenital plate dark brown and pubescent, in ventral view, almost as long as wide, with widely convex posterior border and larger anterior border (Fig. 22H); and in lateral view, longer than tall, with a convex posterior border (Fig. 22I).

Phallic complex. Pseudepiphallic apical lobe truncated and curving inward, covered by small scale-like setae; laterally surrounded by the pseudepiphallic median lobe (Figs. 23A–B); in lateral view, badly surpassing the pseudepiphallic median lobe (Fig. 23D). Pseudepiphallic median lobe well-sclerotized and distinguishable from the pseudepiphallic sclerite and apical lobes; most distal ventral portion projected posteriorly (Figs. 23A– D). Pseudepiphallic sclerite anterior margin, in dorsal view, sinuous, medially incised, and wider than posterior margin; posterior margin slightly incised medially; in lateral view, posterior margin slightly elevated (Fig. 23D). Pseudepiphallic parameres, in ventral view, laterally covered by the pseudepiphallic median lobe (Fig 23B); in axial view, with an oblique sharp edge, bearing several punctuations (Fig. 23C). Ectophallic fold reduced (Fig. 23D). Endophallic cavity very small (Fig. 23A). Endophallic sclerite large and well-sclerotized, with central part connected to lateral appendages only distally and laterally clearly separated (fig. 23A). Endophallic apodeme elongated (Fig. 23A). Rami straight and well-sclerotized (Figs. 23A–B, D).

Female. Similar to the male in coloration and form, differing in the reduced tegmina and sexual structures (Figs. 24A–B). Abdomen, in dorsal view, with first abdominal tergite dark brown (Fig. 24B) and, in lateral view, with a longitudinal dark brown line extending from the base to the apex (Fig. 24A). Supra-anal and subgenital plates light brown, almost translucent, and featuring a dark brown longitudinal median stripe (Fig. 24G). Subgenital plate, in ventral view, wider than long and with the posterior margin bilobed (Fig. 24I); in lateral view, longer than tall and with a convex posterior margin (fig. 24H). Supra-anal plate longer than wide and with a convex posterior margin (Fig. 24G). Ovipositor almost straight, with lateral edges of the ovipositor apex slightly serrulated (Figs. 24E–F).

Measurements (mm).

Males. TL: 4.5–6.1; PL: 0.9–1.1; PW: 1.3–1.4; Tg: 2.2–2.8; HF: 2.9–3.6; HT: 2.4–2.7.

Females. TL: 5.3–6.2; PL: 1.0–1.4; PW: 1.0–1.5; Tg: 0.5–1.3; HF: 3.2–3.7; HT: 2.2–2.9; Ov: 2.1–2.3.

Distribution. This species was originally recorded in the Northern French Guiana (Desutter-Grandcolas 1993), and this is the first record in Brazil, in the Parque Nacional de Sete Cidades, a Brazilian conservation unit dedicated to the integral protection of nature, located in the northern region of the state of Piauí (Map 1). It comprises areas of arid savanna (babassu forests) and transitional zones between savanna, arid savanna, and seasonal forest.