Toxorhinus Lacordaire, 1866

Anderson, Robert S., 2023, A new species of Toxorhinus Lacordaire (Coleoptera: Curculionidae: Dryophthorinae; Rhynchophorini) from Ecuador, Zootaxa 5270 (2), pp. 337-342 : 338

Toxorhinus Lacordaire, 1866

Toxorhinus Lacordaire, 1866: 304 . Type species Sitophilus banonii Guérin-Méneville, 1844 by monotypy.

Complete synonymy is given in Alonso-Zarazaga & Lyal 1999: 65.

Diagnosis: Dryophthorinae with scutellum rhomboidal in shape, the greatest width at or near the middle; rostrum extremely long and slender, as long as length of pronotum and elytra combined (or nearly so),male rostrum denticulate dorsally throughout most of length, apical region of rostrum in both sexes expanded, flat, spatulate; mandibles elongate subtriangular, with inner margins parallel-sided and lacking teeth, not or barely touching medially; antenna with club with basal glabrous part with slender, stalk-like base, width at apex 3–4 times width at base; legs long and slender, femora narrow at base, somewhat abruptly clavate towards apex, tibia narrow on all legs, tarsomeres 1 and 2 extremely long, making up most of tarsal length; color pattern on pronotum and elytra composed of concentrated patches of extremely dense micropilosity contrasted with areas lacking such vestiture.

Identification: The genus Toxorhinus can be recognized by the long, slender rostrum (about as long as the length of the pronotum and the elytra combined) ( Figs 4–6 ) and the mandibles elongate subtriangular, with the inner margins parallel-sided and lacking teeth, not touching medially. The slender, stalk-like base of the glabrous part of the antennal club ( Figs 4–6 ) is a character state not found in other Dryophthorinae . Anderson (2018) presented a key to Neotropical Litosomini .

Diversity: There are two rather widely distributed species of Toxorhinus known, T. banonii ( Guérin-Méneville, 1844) ( Fig. 4 ) and T. grallarius ( Lacordaire, 1866) ( Fig. 5 ). Both are widespread in South America, north into southern Central America ( Anderson 2002). The dorsal patterns of micropilosity are distinctive.

Natural history: Little is known about the natural history of species in this genus. A few specimens of T. grallarius have been associated with dead palms in Brazil ( Anderson 2018).

Figures

FIGURES 4–5. 4, Toxorhinus banonii, oblique habitus; 5, T. grallarius, oblique habitus.

FIGURES 6–7. Toxorhinus amarillo. 6, lateral habitus female paratype. 7, dorsal habitus female paratype.