Anchylorhynchus centrosquamatus Medeiros & Núñez-Avellaneda, 2013, sp. n.

Anchylorhynchus centrosquamatus sp. n.

Figs. 1 C, 2B, 3B, 4

Holoype: Male. Colombia, Casanare, Monterrey, Vereda la Tigrana, 07/VIII/2009, L. Núñez & J. Carreño col. In inflorescence of Syagrus orinocensis. Deposited in ICN.

Paratypes: Colombia, Casanare, Monterrey, Vereda la Tigrana, 15/VII/2008, L. A. Núñez col. (63 5Ƥ MZSP), 07/VIII/2009, L. Núñez & J. Carreño col. (73 25Ƥ ICN)

Description. Length of pronotum + elytra: 5.3–5.9 mm (3) or 4.7–5.7 mm (Ƥ).

Rostrum 1.5–1.6 (3) or 1.6–1.7 (Ƥ) times as long as pronotum; 1.3–1.4 (3) or 1.2–1.4 (Ƥ) times wider at apex than at base; brown to black; with seven longitudinal carinae, all well-defined at base. Head with brown integument, similar or slightly lighter-colored than rostrum. Antennae with straight scape, not reaching the anterior margin of eye; with second antennomere of funicle longer than first and 1.5 times as long as third; club approximately as long as last three funicular antennomeres and roughly as wide as last antennomere of funicle. Pronotum 1.7 (3) or 1.7–1.8 (Ƥ) times wider than long, with lateral margins evenly curved and convergent from base to apex; with brown integument entirely covered by yellow scales; with scales of the median basal area directed either to the center or obliquely to center-base. Prolegs similar in length to meso- and metalegs; with protarsomere I roughly as long as protarsomere III; with protarsomeres I and II slightly wider than long (3) or as wide as long (Ƥ). Elytra 1.4–1.5 (3) or 1.5–1.6 (Ƥ) times as wide as pronotum and 3.5–3.6 (3) or 3.8–3.9 (Ƥ) times as long as pronotum; 1.4–1.5 (3) or 1.4 (Ƥ) times longer than wide; evenly covered by yellow scales; with lateral margins clearly more separated in the middle. Aedeagus 1.9 times longer than wide; slightly wider at opening; with constricted and rounded apex. Apodemes approximately 4 times as long as aedeagus.

Etymology. Named after one of the main diagnostic characters of the species: the pronotal scales directed centrally.

Remarks. This species is very similar in general appearance to Anchylorhynchus amazonicus Voss, 1943. Nonetheless, it can be distinguished by the median basal scales of pronotum obliquely directed toward center-base. In A. amazonicus, these scales are clearly directed backward.

It can also be mistaken for Anchylorhynchus trapezicollis Hustache, 1940 by the elytra distinctly wider at middle and the trapezoidal pronotum. In the latter species, however, the third antennomere of the funicle is about as long as the second, and the pronotal scales are directed forward. Finally, it can be separated from species currently known to occur in Colombia by the seven-carinate rostrum. A. tricarinatus and A. bicarinatus have at most three carinae.

Biological information. Between 5–30 individuals of A. centrosquamatus were seen to visit staminate and pistillate flowers of Syagrus orinocensis (Spruce) Burret (Fig. 4). They enter into the flowers, where they eat pollen and copulate. Females lay their eggs on the staminate and pistillate flowers, at the beginning of anthesis.

Known host species. Syagrus orinocensis (Spruce) Burret.

Type locality. Colombia, Casanare, Municipio Monterrey, Vereda Tigrana baja

Geographical distribution. Known only from the Orinoquia region of Colombia (Casanare, Meta & Guainía), in lowland rain forest or gallery forest in elevations ranging from 150 to 500 m.