Atlanticolycus Nascimento & Bocakova 2023, gen. nov.

Atlanticolycus gen. nov. Type species: Atlanticolycus camposgerais sp. nov.

Diagnosis: Atlanticolycus can be differentiated from all other Eurrhacini by the combination of the following characters: male antennae flabellate with length of branches increasing apically (Figs. 2–6) (filiform in Haplobothris and Neolinoptes Nascimento & Bocakova, 2017); pronotum trapezoidal, wider than long medially (longer than wide in Calocladon, as long as wide [or almost] in Emplectus Erichson, 1847, Neolinoptes and Currhaeus), longitudinal carina on pronotum forming lenticular areola (areola absent, or very slender in Lycoplateros and Neolinoptes) (Fig. 1); elytra with primary costa 3 absent in distal 1/3; male genitalia with short phallus, 1.4–1.5× longer than phallobase, curved ventrally in lateral view, with apical projections dorsally-oriented (unique among Eurrhacini), ventrally-oriented apex and with internal sac bearing apical sclerites (similar to some Lycoplateros); parameres as long as phallus, apically rounded with ventral subapical short thorns (unique among Eurrhacini), and joined basally by a strong ring-like bridge (similar to Calocladon and some Cladocalon), phallobase asymmetrical, as long as half of parameres length (Figs. 7–16). Female genitalia with coxites medially arcuately emarginate and basal portion of coxites forming slender transverse fusion (unique feature in Eurrhacini, similar character state present only in Caenia Newmann, 1838 (Calopterini)) (Figs. 17–18).

Description: Head partially covered by pronotum. Eyes medium to large, eye diameter 1.4–1.8× longer than interocular distance (Fig. 1). Male antennae flabellate, antennomeres 3–5 subequal, length of branches increasing apically. Female antennae serrate. Labrum anteriorly emarginate. Mandibles well developed, curved. Maxillary palps elongate, ultimate palpomere apically rounded, apical margin flattened dorsoventrally, palpomere 2 and 4 subequal, and 2–3.3× longer than 3. Labial palps short, ultimate palpomere apically rounded, apical margin flattened dorsoventrally. Pronotum trapezoidal, wider than long medially, basal margin bisinuous, median longitudinal carina with lenticular areola occupying median 1/2 to 2/3, connected to posterior margin often by a very short longitudinal carina, sometimes areola directly connected to posterior margin (Fig. 1). Scutellum distally straight to medially notched. Prosternum triangular to trapezoidal, mesoventrite trapezoidal. Elytra elongate, each elytron with four strong primary costae, costae 2 and 4 more elevated and costae 1 and 3 more elevated in basal 1/3, primary costa 3 absent in distal 1/3. Elytra with five weak secondary costae, intercostal intervals provided with irregular cells (Figs. 2–6). Legs slightly flattened, trochanters elongate, conical, hind tibiae as long as femora, 2.6–3.1× longer than trochanters. Male ventrite 8 elongate, quite asymmetrical, with the basal half mostly transparent. Male genitalia with phallus bent dorsally in lateral view, relatively short (comparing to phallobase), with hooked dorsoapical projections (Fig. 7a), and apex slightly to strongly ventrally-oriented (Fig. 7b); parameres elongate, as long as phallus taking into account the ventrobasal ring-like bridge joint, apically rounded with apical/subapical short thorns (Figs. 7, 9, 11, 13, 15c), phallobase asymmetrical, as long as half of parameres length (Fig. 7–16). Female genitalia with valvifers about twice as long as ventral bridge, coxites long, medially arcuately emarginate with basal portion transversely fused, styli about half the length of valvifers, dorsal elongate structures bearing a plate apically, positioned between the coxites (Figs. 17–18). Body length: 5.6–6.8 mm, humeral width: 1.3–1.6 mm.

Etymology: The name of the new genus refers to its known geographical distribution, the Brazilian Atlantic Forest.

Distribution: Brazil (Fig. 19).

Composition: Atlanticolycus gen. nov. comprises five new species described below.

Comments: All species of the genus have been collected in or near protected areas (Conservation Units) of the Brazilian Atlantic rainforest.