Mberu lamasi sp. nov.

(Figs 12, 13)

Description. Male. Body length: 2.66–2.87 mm. Wing length: 2.60–2.74 mm long, 0.70–0.84 mm wide (n = 10) (Fig. 12A). Similar to Mberu amorimi sp. nov. in both general habitus and chaetotaxy, except as noted. Body mostly black to dark brown, with slight blue or green reflections. Head (Fig. 12B). Frons width 1/3 head width; vertex slightly excavated dorsally; face with dense silver pruinosity; clypeus dark brown, with silver pruinosity on edges; palpus dark brown, yellowish on edges and apex; postpedicel brown, triangular and pubescent, about 1.4 times longer than basal width; stylus about 4.1 times longer than postpedicel. Thorax. Dark brown, with some green or blue reflections, as long as abdomen; 4–5 dc s, increasing in size posteriorly; one presut spal s and two large psut spal s; two dark pprn s, one strong and one tiny. Wing. RMx ratio = 4.5, CuAx ratio = 0.3. Legs. Completely brown, coxa II and III sclerotized. Leg I. Coxa I with dorsal hook-shaped projection at apex (Fig. 12C) (MSSC); femur I with ventral excavation at apex; tarsomere 1 elongated, as long as remaining tarsomeres combined, with 5–6 small dark av, similar to spines (Fig. 12D). Leg II. Femur II with row of dark setae on anterior surface; ventral surface bare, except av row of dark setae on apical half and one strong, brown pv seta near apex; with ventral excavation at apex (all MSSC). Leg III. Femur III with apical pv and ventral excavation at apex; tibia III (Fig. 12E) with dorsal swelling at apical half, row of dorsal and ventral white setae and comb of posterior pale setae projecting into IIIt1; IIIt1 with comb of posterior white setae projecting into IIIt2, with ventral excavation at base (MSSC). Relative podomere ratios: I: 8.7/ 8.6/ 4.8/ 2.3/ 1.6/ 1.3/ 1; II: 8.6/ 8/ 5.7/ 3.1/ 2.1/ 1.3/ 1; III: 7.9/ 8.1/ 2.8/ 3/ 2/ 1.3/ 1. Abdomen. Mostly black to dark brown, with some dark blue to green reflections. Hypopygium (Fig. 13). Epandrium elongate, twice longer than high, dark (Fig. 13A, B). MEp digitiform, with two small dorsal setae near apex (Fig. 13C, E). DSur and VSur covering internal appendages (Fig. 13A, B); VSur (Fig. 13C) enlarged, twice higher than DSur, with one internal seta at apex, probably being LEp fused with VSur (see Quevedo et al., 2025); DSur (Fig. 13D) irregularly shaped and robust, with curved ventral margins and truncated, rounded distal lobe, 3.2 times wider than height. Hypandrium basally fused to epandrium. Phallus with short dorsal projection near apex (Fig. 13G). Cercus (Fig. 13F) divided in two parts, ventral part rounded and stout, with 4–5 spines ventrally, dorsal part rounded and covered by fine setae, with flattened seta apically. Female. Body length: 2.83–2.90 mm. Wing length: 2.89 mm long, 0.95–0.97 mm wide (n = 5). Similar to male, except as noted. Head. Face broader (about as broad as ocellar tubercle). Wing. RMx ratio = 5.3, CuAx ratio = 0.3. Legs. Leg II. Tibia II with av at 1/4, 1/2, 3/4 and at apex, one anterior seta at apex, two ad at 1/3 and 2/3, and two dorsal setae at 2/3 and at apex. Relative podomere ratios: I: 8.6/ 8.3/ 4.8/ 3/ 1.6/ 1/ 1.1; II: 13.6/ 13.2/ 8.9/ 4.9/ 3.3/ 2/ 1; III: 9.4/ 11.1/ 3.2/ 4.1/ 2.3/ 1.5/ 1. Abdomen. Tergites 1–5 covered by short setae. Oviscapt as in M. bodoquena sp. nov.

Type material. HOLOTYPE ♂, “SISBIOTA - | CNPQ/FAPESP [Vertical line] | BRASIL, MS [Mato Grosso do Sul], Bodoquena | 20º41′55.9″S 56º52′49.4″W | Malaise 6, 5-20.ii.2012, | Lamas, Nihei et al. leg.”; “HOLOTYPE | Mberu lamasi | Silva, Capellari & Oliveira [red label]” (MZUSP) . Holotype in good condition, genitalia not dissected. PARATYPES. Brazil. Mato Grosso do Sul. Same data as holotype (6 ♂, 4 ♀, MZUSP) . Same data, 21.iii–06.iv.2012 (1 ♀, MZUSP) . Same data except, 20º41′49.9″S 56º52′54″W, Malaise 4 - 6–21.i.2012 (6 ♂, one dissected, 2 ♀, MZUSP) . Rio Grande do Sul. Arroio Corrientes, Fazenda Corrientes, Paleodunas, Malaise - 29.x– 6.xi.2011, 31°33′51.7″S 52°08′22.2″W, F.D. Kirst & R.F. Kruger col. (1 ♂, INPA) ; Arroio Pelotas, 27.x–04.xi.2011, Malaise Areal, 31°43′18.3″S 52°15′15.2″W, F.D. Kirst & R.F. Kruger col. (1 ♂, dissected, MZUSP) . Paraguay. Caaguazú. Coronel Oviedo, 1971, L Peña leg. (2 ♂, one dissected, MZUSP) .

Additional material. Argentina. Corrientes. Corrientes City, 27°25′26.6″S 58°43′55.4″W, 09.xi.2022, Matias Ignacio Dufek col., hand net, Universidad Nacional del Nordeste (1♂, 1♀, UNNE) .

Etymology. Named after the Brazilian dipterist Carlos Lamas (MZUSP), one of the collectors of the type series of this species.

Remarks. Mberu lamasi sp. nov. is similar to M. soaresi sp. nov., both have tibia III with dorsal swelling on apical half, comb of posterior pale setae projecting into IIIt1, projecting towards tarsal excavation (Figs 12E, 18E), and the hypopygial morphology is similar to the pepocatu group, but can be differentiated by coxa I with conspicuous hook-shaped projection in M. lamasi sp. nov. (Fig. 12C) and It1 with distinct row of setae similar to spines (Fig. 12D) (coxa I without conspicuous projection (Fig. 18C) and It1 without distinct row of setae (Fig. 18D) in M. soaresi sp. nov.).

Matias Dufek (pers. comm.) reported that he collected this species emerging from a cactus in a region of the Argentinian Chaco, and the identification was confirmed with photos sent by him. Parent (1933) described a female from San José (Northern Bolivia) as an uncertain genus (“Genre?”) suggesting it would be placed in Medeterinae . Photos of the specimen (currently in the Staatliches Museum für Naturkunde Stuttgart, Germany) proved that it belongs to Mberu and is probably conspecific with M. lamasi sp. nov.

Distribution (Fig. 24). Argentina: Corrientes; Paraguay: Coronel Oviedo (Chaco biome); Brazil: states of Mato Grosso do Sul (Cerrado biome) and Rio Grande do Sul (Pampa biome).

Comments. Mberu lamasi sp. nov. is one of the morphospecies collected in Mato Grosso do Sul (Brazil) during SISBIOTA-Diptera Brazilian Network (see Lamas et al. 2023).