Prionobrachium Faust, 1894

Legalov, Andrei A., 2024, First record of the genus Prionobrachium Faust, 1894 (Coleoptera: Curculionidae) from Colombian copal, Ecologica Montenegrina 79, pp. 113-117 : 114-115

Genus: Prionobrachium Faust, 1894

Type species: Prionobrachium schoenherri Faust, 1894

Prionobrachium gusakovi sp. n. ( Fig. 1 )

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Type material: Holotype ( CVGM), Colombia, Colombian copal, Holocene.

Type strata and locality. Colombian Quaternary copal; Santander Department, Andes region, Columbia, South America .

Description. Body black. Antennae and legs brown. Body convex dorsally. Light scales located on forehead, sides of rostrum, base of pronotum, last interval on apical third of elytra, thorax, abdomen and legs. They thicken on interval 3 of elytra in the first half and metanepisterna. Head capsule not constricted behind eyes, 0.3 times as long as rostrum. Mandibles large. Rostrum long, distinctly curved, flattened on sides, with two lateral carinae, with one carina in middle, 3.6 times as long as wide at apex, 3.3 times as long as wide in middle, 2.7 times as long as wide at base; dorsal surface of rostrum with carina. Antennal scrobes directed under but not reaching eyes and not reach them. Antennae long, thin, geniculate, inserted in apical third of rostrum. Antennomeres subconical. Antennomere 1 not reaching eyes. Club compact, 2.3 times as long as wide in middle. Eyes oval, not protruding from head. Temples short. Forehead quite wide, narrow than rostrum base wide, flattened. Pronotum bell-shaped, with weakly arcuate sides, 1.1 times as long as length of rostrum, 1.1 times as long as wide at apex, 0.7 times as long as wide at middle and at base. Disc weakly flattened, very rarely and finely punctate. Elytra quite wide, 2.8 times as long as pronotum, 1.2 times as long as wide at base, 1.1 times as long as wide at middle, 1.9 times as long as wide at apical fourth; with slightly smoothed humeri. Interstriae flat, 4.0- 6.0 times as long as wide of striae, smooth. Punctate striae narrow. Striae 9 and 10 not merging at level of mesocoxae. Prosternum without ventral channel and postorbital lobe. Precoxal portion of prosternum quite long, 0.5 times as long as precoxal cavity length. Procoxal cavities rounded, located before base of prosternum, separated. Postcoxal portion of prosternum 0.4 times as long as length of precoxal cavity length. Mesocoxal cavities rounded and separated. Metacoxal cavities transverse, quite wide. Metaventrite convex, 1.7 times as long as metacoxal cavity. Metanepisterna 8.0 times as long as wide in middle. Abdomen flattened. Ventrites 1–5 oriented in one plane. Ventrites 1 and 2 fused. Ventrites 1- 3 subequal in length. Ventrite 1 0.8 times as long as metacoxal cavity. Ventrite 2 1.2 times as long as ventrite 1. Ventrite 3 0.9 times as long as ventrite 2. Ventrite 4 0.6 times as long as ventrite 3. Ventrite 5 2.1 times as long as ventrite 4, without anal setae. Legs long. Forelegs enlarged. Metacoxae much not reaching elytra. Trochanters not separating femora and coxae. Femora thickened and rarely punctate. Profemur with large triangular teeth serrate on anterior margin. Meso- and metafemur without teeth. Profemur 2.5 times as long as wide. Mesofemur 4.1 times as long as wide. Metafemur about 3.3 times as long as wide. Tibiae with apical comb of setae, with uncus and two distinct groups of setae. Uncus almost as long as claws. Protibia stark curved, 5.7 times as long as wide in middle, with mucro. Meso- and metatibia almost straight, without mucro. Mesotibia 4.3 times as long as wide in middle. Metatibia 6.0 times as long as wide in middle. Tarsi quite long, pseudoquadrisegmented. Tarsomeres 1 and 2 trapezoidal. Tarsomere 3 bilobed. Tarsomere 5 long. Protarsi: tarsomere 1 1.8 times as long as wide; tarsomere 2 subequal in length and wide, 0.7 times as long as and 1.2 times as wide as tarsomere 1; tarsomere 3 0.7 times wider than length, 0.8 times as long as and 1.3 times as wide as tarsomere 2; tarsomere 5 3.5 times as long as wide, 1.4 times as long as and 0.3 times as narrow as tarsomere 3; mesotarsi: tarsomere 1 1.8 times as long as wide; tarsomere 2 1.3 times as long as wide, 0.7 times as long as and of same width as width to tarsomere 1; tarsomere 3 0.8 times wider than length, 1.2 times as long as and 2.0 times as wide as tarsomere 2; tarsomere 5 5.0 times as long as wide, 1.7 times as long as and 0.3 times as narrow as tarsomere 3; metatarsi: tarsomere 1 1.2 times as long as wide; tarsomere 2 0.9 times wider than length, 0.8 times as long as and 1.1 times as wide as tarsomere 1; tarsomere 3 0.7 times wider than length, subequal in length and 1.3 times as wide as tarsomere 2; tarsomere 5 4.0 times as long as wide, 1.6 times as long as and 0.3 times as narrow as tarsomere 3. Claws free, dentate at base. Total body length (without rostrum) 4.1 mm. Length of rostrum 1.0 mm.

Etymology. The epithet of this new species is dedicated to Viktor A. Gusakov ( Moscow).

Localisation. Colombia ( Santander Department).

Comparison. The new species differs from Prionobrachium nigrum Hustache, 1938 in the rare and finely punctate pronotum, smooth elytral interstriae, white scales forming a stripe in the first half of the third elytral interstria, and the last interstria in the apical third of the elytra with white scales.

Figures

Figure 1. Prionobrachium gusakovi sp. n., holotype, habitus: A – lateral view, left; B – lateral view, right; C – dorsal view; D – ventral view. Scale bar = 1.0 mm.