Merucata contiae Soares, Camargo & Lamas sp. nov.

(Figs 8, 9, 20)

Diagnosis (male). Easily recognized by the mystax composed of sparse macrosetae, not forming a dense ventral tuft (Fig. 8C, D); femora mostly reddish brown, except ventral surface, black (Fig. 8A, D); wing hyaline light brown, bifurcation of vein R 4 and R 5 distinctly distal to apex of discal cell (Fig. 8F); terminalia wider than tergite 8 in dorsal view (Fig. 9A); hypandrium with short concavity at middle of posterior edge, covered with long and slender tuft of setae (Fig. 9K); gonocoxite broad basally, slightly narrowing towards somewhat spear-shaped apex, mid-dorsal margin with a concave indentation at it mid-length, external surface sparsely setose (Fig. 9F).

Description. Holotype male (Fig. 8A). Body Length: 9.7 mm; wing length: 8.6 mm. Similar to M. caipora sp. nov., except as noted: Head (Fig. 8A, C, D). Face wholly silvery pruinose; mystax composed with sparse macrosetae mixed black dorsally and white ventrally, not forming dense tuft of macrosetae below. Frons covered with golden pruinosity, except by short triangular area between ocellar tubercle and base of antenna black in anterior view; orbital setae yellow; occipital setae black; upper-most 5–6 postocular macrosetae black. Thorax (Fig. 8A, B, D). Antepronotum with row of short black macrosetae. Scutum covered with long setae at posterior margin, with median black stripe narrow, and mostly divided into two stripes, not reaching posterior margin of scutum; 2–3 black postsutural dorsocentral macrosetae, 2 black postalar macrosetae, dorsal surface of scutellum covered with scattered mixed white and black short setae. Legs (Fig. 8A, C–E). Mostly reddish brown, except anteroventral surface of femora, apex of tibiae and apical tarsomeres black. Leg I. Anterior surface of coxa with dense, slender white macrosetae. Femur mostly covered with white setae; ventral surface with rows of white and slender macrosetae at basal 2/3. Tibia with ventral to anteroventral row of 2–3 white macrosetae from basal 2/3 to apex. Leg II. Femur II covered with short white setae, longer at basal 1/3; 3 short, strong anteroventral setae at apical 2/3, 1 short anterior seta at apical 1/2. Leg III. Femur covered with short white setae; ventral row with 3–4 short white macrosetae, and 1 short preapical black macroseta, 1 antero and 1 posterodorsal preapical short macrosetae. Wing (Fig. 8F). Hyaline light brown, veins brown. Bifurcation of vein R 4 and R 5 at distance of one crossvein m-m distal to apex of discal cell; petiole of cell cua short, as long as humeral vein. Abdomen (Fig. 8B). Lateral and posterior margins of tergites 2–6 covered with silvery pruinosity, except tergite 5 mostly coppery pruinose, and tergite wholly silvery pruinose.

Tergite 1 with 2–3 black lateral macrosetae and posterior row of short black setae; tergites 2–7 with lateral mixed black and white macrosetae, sternites wholly covered with weak silvery pruinosity. Tergite 8 narrowing at middle of anterior and posterior edges; posterior corners with black macrosetae (Fig. 9H). Sternite 8 somewhat rectangular, with narrow concavity at middle of anterior edge, and posterior row of long black macrosetae (Fig. 9I). Terminalia (Fig. 9). Orangish-brown (Fig. 9A, B). Epandrium broad in dorsal view, somewhat subrectangular in lateral view; inner edge with wide median short digitiform dorsal process, almost reaching apex of epandrium; inner margin of dorsal process covered with dense, short spine-like macrosetae; apical edge of epandrium with comb of short macrosetae (Fig. 9A–D). Hypandrium somewhat saddle-shaped, posterior margin with short concavity at middle, covered with dense black macrosetae; posterior corners with short setae (Fig. 9K). Gonocoxite mostly squared basally, abruptly narrowed at apical 1/2, with apicodorsal projection covered with spicules; basal 1/2 of outer edge covered with short setae, with a few macrosetae at basoventral margin (Fig. 9E, F). Gonostylus longer than gonocoxite, mostly knife-shaped, weakly sclerotized at middle; apicoventral margin and inner edge with short denticles; base with short concavity, forming short triangular lobe dorsally (Fig. 9E, J).

Female: Body length: 10.6–12.45 mm, wing length: 7.5–9.3 mm (n = 10). Similar to male, except as noted: face and frons mostly golden pruinose. Terminalia as in M. caipora sp. nov.

Variation. Body length: 9.7–11.8 mm, wing length: 7–9.4 mm (n = 10). Mystax with mixed black and white macrosetae, katatergite with mixed black and white macrosetae, femora almost entirely reddish-brown.

Type material. HOLOTYPE ♂ (MZUSP) labelled: “ BRASIL, MS [Mato Grosso do Sul], Aquidauana | Res. Ecol. UEMS—Mata Ciliar | Corrego Fundo | 20°26'07.2"S 55°39'32.8"W | Malaise 09 | 11–26.ix.2011 | Lamas, Nihei & eq. col. Holotype condition: Good, not dissected. PARATYPES: Same data as holotype (7 ♂, 1 ♀, MZUSP); Same data, except: 26.ix–11.x.2011 (8 ♂, 3 ♀, MZUSP); same data, except: 11–26.x.2012 (2 ♂, 3 ♀, MZUSP); same data, except: 11–26.x.2011 (2 ♂, MZUSP); same data, except: 26.x–11.xi.2011 (1 ♂, 2 ♀, MZUSP); same data, except: 26.xi–11.xii.2011 (2 ♂, 1 ♀, MZUSP); same data, except: 26.ix–11.x.2012 (1 ♂, 1 ♀, MZUSP); same data, except: 26.xi–11.xii.2012 (2 ♀, MZUSP); same data, except: 26.x–11.xi.2012 (2♂, MZUSP); same data, except: 11– 26.xi.2011 (2 ♀, MZUSP); same data, except: 11–26.ix.2012 (1 ♂, MZUSP); same data, except: Vegetação Aberta, Floresta Estacional Decidual 20°25'59.0"S 55°39'20.8"W, Malaise 08, 11–26.ix.2011 (8 ♂, 6 ♀, INPA); same data, except: 11–26.x.2012 (3 ♂, 4 ♀, MZUSP); same data, except: 26.ix–11.x.2011 (17 ♂, one dissected, 3 ♀, MZUSP); same data, except: 11–26.ix.2012 (5 ♂, MZUSP); same data, except: 11–26.x.2011 (4 ♂, 4 ♀, NHMW); same data, except: 26.x–11.xi.2011 (4 ♂, 1 ♀, MZUSP); same data, except: 11–26.xi.2011 (1 ♂, dissected, 3 ♀, MZUSP); same data, except: 26.viii–11.ix.2012 (2 ♂, MZUSP); same data, except: 26.ix–11.x.2012 (3 ♂, 2 ♀, MZUSP; 1 ♂, 1 ♀, NHMW); same data, except: 26.vi–11.vii.2012 (1 ♂, MZUSP); same data, except: 11–26.viii.2012 (1 ♂, MZUSP); same data, except: 11–26.xii.2011 (1 ♀, MZUSP); same data, except: Vegetação Fechada, 20°26'03.7"S 55°39'20.8"W, Malaise 07, 11–26.x.2012 (3 ♂, 2 ♀, MZUSP); same data, except: 11–26.x.2011 (4 ♂, 1 ♀, MZUSP); same data, except: 11–26.ix.2012 (2 ♂, 2 ♀, MZUSP); same data, except: 26.x–11.xi.2012 (2 ♂, MZUSP); same data, except: 11–26.xi.2011 (2 ♂, one dissected, 1 ♀, MZUSP); same data, except: 26.x–11.xi.2011 (1 ♂, NHMW; 1 ♀, MZUSP); same data, except: 11–26.viii.2012 (1 ♂, MZUSP); same data, except: 26.viii–11.ix.2012 (1 ♂, MZUSP); same data, except: 26.ix–11.x.2012 (1 ♀, MZUSP); Porto Murtinho, 21°40'59.7"S 57°46'42.5"W, Malaise 31, 10–25.i.2012, Lamas, Nihei & eq. cols. (1 ♀, MZUSP); Corguinho, Taboco, Reserva Quinta do Sol, 19°46'40.8"S 55°14'59.0"W, Malaise 12, 29.viii–12.ix.2012, Lamas, Nihei & eq. cols. (1 ♂, MZUSP).

Remarks. This new species is similar to M. pujoli sp. nov. based on the fact that both possess bicolored femora, however M. pujoli sp. nov. has a complete yellow scape and pedicel (Fig. 15D), epandrium narrower than tergite 8 in dorsal view (Fig. 16A), and gonocoxite without concave indentation on its mid-dorsal length (Fig. 16E, F), contrasting, the antenna is wholly black (Fig. 8D), the epandrium is wider than tergite 8 (Fig. 9A) and the gonocoxite abruptly narrowed at apical 1/2, with an apicodorsal projection covered with spicules (Fig. 9E, F) in M. contiae sp. nov. This new species can also be considered similar to M. cerradensis sp. nov. based on the shape of male epandrium, broad at distal half in lateral view. However, in the latter the epandrium is somewhat oval in dorsal view and the gonocoxite does not possess a concave indentation on its mid-length dorsally.

Merucata contiae sp. nov. was the most frequently sampled species of the genus, with a total of 143 specimens examined (94 males and 49 females). Interestingly, the vast majority of specimens (141) were collected in the Ecological Reserve of the State University of Mato Grosso do Sul (UEMS), located in the municipality of Aquidauana. Additional material is represented only by a single female specimen collected in the city of Corguinho and one male in Porto Murtinho. No specimens of M. contiae sp. nov. were found in the municipality of Corumbá, at the Pantanal Research Station ( Base de Estudos do Pantanal — BEP) of the Federal University of Mato Grosso do Sul (UFMS), nor in the municipalities of Bodoquena and Rio Verde, despite similar sampling efforts being conducted across all these localities (Lamas et al. 2023).

The high degree of endemism observed highlights the strategic importance of the UEMS Biological Reserve for biodiversity conservation. The municipality of Aquidauana, where the reserve is located, lies in the west-central portion of the state of Mato Grosso do Sul, between latitudes 18°35'18.2893"S and 20°30'50.3655"S, and longitudes 56°59'57.9281"W and 55°03'32.3429"W. A defining feature of this region is its location at the interface between the Pantanal lowlands and the Maracaju-Campo Grande Plateau, which contributes to its rich biodiversity typical of ecotonal environments (Rodrigues et al. 2017).

The concentration of endemic species in this reserve underscores its role as a critical refuge and reinforces the need for continued scientific investigation and conservation efforts aimed at preserving the ecological integrity of this biologically diverse transition zone.

Distribution. The new species is recorded only from the state of Mato Grosso do Sul, in Central-West Brazil, in biomes of Cerrado and Pantanal (Fig. 20)

Etymology. Named after Camila Conti, biologist and technician at the Laboratório de Diptera (MZUSP), in recognition of her essential contribution to the maintenance and organization of the Diptera collection, as well as her active involvement in the fieldwork, including the collection, sorting, and preparation of specimens.