Merucata Soares, Camargo & Lamas gen. nov.

Type species: Merucata caipora Soares, Camargo & Lamas sp. nov. by present designation. Type locality: Brazil, state of Mato Grosso, Poconé .

Etymology. From the Tupi-guarani meru = fly and cata = savanna-like vegetation, alluding to the known distribution of the genus occurring mainly in the Cerrado biome (Brazilian Savanna). The gender is feminine.

Included species. Merucata caipora Soares, Camargo & Lamas sp. nov. (Brazil, states of Goiás, Mato Grosso, Mato Grosso do Sul and Tocantins), M. capixaba Scorpione, Soares & Camargo sp. nov. (Brazil, state of Espírito Santo), M. cerradensis Soares, Camargo & Lamas sp. nov. (Brazil, state of Mato Grosso), M. contiae Soares, Camargo & Lamas sp. nov. (Brazil, state of Mato Grosso do Sul), M. curupira Soares, Camargo & Lamas sp. nov. (Brazil, state of Piauí), M. elliptica (Scarbrough & Perez-Gelabert, 2010) comb. nov. (Trinidad and Tobago and newly recorded from Venezuela), M. pujoli Scorpione, Soares & Lamas sp. nov. (Brazil, Federal District), and M. vieirai Soares, Camargo & Lamas sp. nov. (Brazil, state of Mato Grosso do Sul).

Diagnosis. Head (e.g., Figs 1C, D, 6C, D, 8C, D). Scape about 2 times longer than pedicel; postpedicel lanceolate, slightly tapered distally, about as long as scape and pedicel combined, apical 2/3 covered with squamiform setae; stylus with two bare elements, slightly longer than postpedicel and abruptly tapered at apex; frons with convergent slopes; face slightly gibbose at lower 1/3 to 1/2 with dorsal margin sloping very gradually to facial plane; mystax dense to sparse, occupying entire facial gibbosity; palpus short, one-segmented. Thorax (e.g., Figs 1A, B, 12B, D, 17A, B). Scutum tumid, 1–6 pairs of postsutural dorsocentral macrosetae (sometimes slightly thinner than other macrosetae of thorax), 2 notopleural macrosetae, 1 supra-alar and 1–2 postalar macrosetae; dorsal anepisternal seta absent, posterior anepisternal setae white; scutellum tumid as scutum, without impressed rim on posterior border; 2 scutellar macrosetae on posterior border, with sparse, fine, short setae on disc; anatergal setae absent; katatergite with row of white or mixed white and black macrosetae, meron + metanepisternum with slender white setae; postmetacoxal bridge absent, postmetacoxal area entirely membranous. Wing (e.g., Figs 1E, 4E, 8F, 10E). Cell r 1 closed before wing margin; without costal dilatation; bifurcation of R 4+5 at level or after apex of discal cell; R 5 ending after wing apex; supernumerary stump crossvein on R 4 absent (sometimes present only in one wing, but not forming cell (Figs 10E, 12E)); cells m 3 and cua closed. Legs (e.g., Figs 1A, 10A, 15A). Femora mostly covered with short white setae (except in M. capixaba sp. nov. with anterior and dorsal surfaces wholly covered with black setae (Fig. 4A, D)); empodia and pulvilli present. Abdomen (e.g., Figs 1A, B, 2A, B, 3A, B, 10A, B). Mostly covered with black setae; tergite 1 with distinct macroseta laterally; tergites 2–8 with row of macrosetae at posterior margin (usually longer laterally and diminishing in size towards dorsal posterior margin, sometimes indistinguishable from remaining dorsal setosity); sternites without macrosetae. Terminalia (Figs 2, 5, 7, 9, 11, 14, 16, 18). Narrow (as wide as tergite 8 (e.g., Figs 1A, 14A)) or wide (wider than tergite 8 (e.g., Figs 7A, 9A)) in dorsal view. Epandrium with inner dorsal process, covered with short spiniform macrosetae, with apicoventral projection in M. curupira sp. nov. (Fig. 11B, D); hypandrium usually with posterior row of slender to strong macrosetae (e.g., Figs 2L, 5J, 9K); phallus divided into three long prongs, encompassing about half of phallus length (e.g., Figs 2G, 5G, 9G).

Female. Similar to male, except abdomen tapering towards apex and presence of three spermathecae (Fig. 3).

Remarks. In the identification key provided by Papavero et al. (2009), the new genus runs to the Myaptex group, based on the following set of characters: antennal stylus bare; subalar sclerite without conical projection; anatergite bare; scutellum with at least one pair of well-developed marginal macrosetae and without an impressed rim; wing with only two submarginal cells; costal section between tips of veins R 5 and M 1 subequal to or much shorter than costal section between tips of veins R 4 and R 5 (i.e., R 5 ends after wing apex); claws acute; abdominal tergites 2–8 with posterolateral macrosetae; male terminalia not forming an angle of 90° with body axis.

Using the most recent key for the Myaptex group of genera (Soares et al. 2025), Merucata gen. nov. keys to couplets 8 and 9. To avoid ambiguity and facilitate accurate identification, the final two couplets of the key have been revised and updated to accommodate the new genus. This revision was necessary primarily due to variability at the base of vein R 4, which can lead to misidentification. In some species of the new genus, this vein is slightly angled, while in others it appears nearly straight. Additionally, one of the characters used in couplet 8 of the key by Soares et al. (2025), “mystax restricted to middle of face, resembling a mohawk”, was based on a misidentified specimen. The specimen shown in figure 12 (A, B) of that work does not belong to Martintella, but is in fact a representative of Nevadasilus Artigas & Papavero, 1995 .

At first glance, without running the specimens through a key, they may resemble representatives of Eicherax Bigot. However, they can be easily differentiated by the presence of posterolateral macrosetae on abdominal tergites 2–8. The genus may also resemble Eichoichemus Bigot, but differs by the presence of only two submarginal cells and acute claws. Interestingly, the phallus of the new genus is similar in general shape to that of Triorla Parks, with about half of its length composed of three divided prongs, including a similarly shaped short fan-like ejaculatory apodeme directed anteriorly in both genera. However, Triorla can be easily separated from the new genus by the longer distance between tips of veins R 5 and M 1, and absence of ocellar setae.

Distribution. The new genus is mainly distributed in Brazil, ranging from the state of Piauí (Northeast region) to Mato Grosso do Sul (Central-West region), near to the border with Paraguay. It occurs across multiple biomes, including the Atlantic Forest, Caatinga, Cerrado and Pantanal. Merucata elliptica comb. nov. is the only species recorded outside Brazil; originally described from Trinidad and Tobago, it is newly recorded from Venezuela (Figs 19, 20).

Key to males of species of Merucata gen. nov.

1 All femora and tibiae black (e.g., Figs 1A, 4A).............................................................. 2

- Femora and/or tibiae partly yellow to orangish (e.g., Figs 8A, E, 10A, 12A)....................................... 5

2 Face mostly covered with golden pruinosity (Fig. 4C); anterior surfaces of femora II and III covered with black setae (Fig. 4A, D); epandrium glove-shaped in lateral view (Fig. 5B, D) [Brazil: Espírito Santo]................... M. capixaba sp. nov.

- Face mostly covered with silvery pruinosity (e.g., Figs 1C, 6C); anterior surfaces of femora II and III mostly covered with white setae (e.g., Figs 1A, 6A); epandrium subrectangular in lateral view (e.g., Figs 2B, D, 7B, D).......................... 3

3 Mystax occupying 2/3 of face, composed of mixed black and white macrosetae, not forming dense tuft of macrosetae on ventral margin (Fig. 6C, D); male terminalia wider than tergite 8 in dorsal view (Fig. 7A); inner margin of inner process of epandrium obscured by dense, short and black macrosetae (Fig. 7C) [Brazil: state of Mato Grosso]........... M. cerradensis sp. nov.

- Mystax occupying 1/2 of face, composed of white macrosetae (only a few black setae at middle of face) forming dense tuft of white macrosetae on ventral margin (Figs 1C, D, 17C, D); male terminalia as wide as tergite 8 in dorsal view (Figs 2A, 18A); inner margin of inner process of epandrium not obscured by dense, short and black macrosetae (Figs 2C, 18C)........... 4

4 Anterior surface of femur I with short black setae (rarely with a few sparse white setae), ventral surface mostly bare, with a few sparse short white setae (Fig. 1C); 1 postalar macroseta; apical 1/3 of anterior surface of femora II and III covered with short black setae (Fig. 1A); hypandrium with apical tuft of black macrosetae at middle of posterior edge (visible without dissection) (Fig. 2B, L) [Brazil: Goiás, Mato Grosso, Mato Grosso do Sul and Tocantins]...................... M. caipora sp. nov .

- Anterior surface of femur I with short white setae, ventral surface with short white setae and row of slender white macrosetae at basal 1/2 (Fig. 17C); 2 postalar macrosetae; anterior surface of femora II and III wholly covered with white setae (Fig. 17A); hypandrium only with sparse posterolateral macrosetae (Fig. 18K) [Brazil: Mato Grosso do Sul]........ M. vieirai sp. nov.

5 Femora dark brown to black anteroventrally and pale brown to orangish dorsally and posteriorly; tibiae entirely orangish or brownish with basal third slightly orangish (Figs 8A, D, 15 A, C)............................................... 6

- Femora wholly dark brown to black; tibiae entire orangish or with orangish basal half and brownish distal half (Figs 10A, 12A)............................................................................................... 7

6 Antenna with scape and pedicel mostly yellow to orangish (Fig. 15C, D); abdominal sternites pale brown (Fig. 15A); male terminalia as wide as tergite 8 in dorsal view (Fig. 16A); hypandrium almost bare, only with a few short and slender setae (Fig. 16K) [Brazil: Federal District].............................................................. M. pujoli sp. nov.

- Antenna wholly black (Fig. 8C, D); abdominal sternites dark brown to black; male terminalia wider than tergite 8 in dorsal view (Fig. 9A); hypandrium with dense macrosetae (Fig. 9K) [Brazil: Mato Grosso do Sul]................. M. contiae sp. nov.

7 Wings with bifurcation of R 4 and R 5 at apex of discal cell (Fig. 12E); apicoventral margin of epandrium not projected (Fig. 14D); inner margin of epandrium with short digitiform dorsal process (Fig. 14C) [Trinidad and Tobago and Venezuela]........................................................ M. elliptica (Scarbrough & Perez-Gelabert, 2010) comb. nov.

- Wings with bifurcation of R 4 and R 5 after apex of discal cell (Fig. 10E); apicoventral margin of epandrium projected, forming rounded lobe (Fig. 11B, D); inner margin of epandrium with wide dorsal process (Fig. 11C, D) [Brazil: Piauí]................................................................................................. M. curupira sp. nov.