Notes on the taxonomy of some "Astaena" species described by Burmeister (Coleoptera: Scarabaeidae: Melolonthinae).

In the framework of the taxonomic revision of South American Sericini (Coleoptera: Scarabaeidae: Melolonthinae), we examined the type specimens of the species described by Burmeister (1855) in the genus Astaena Erichson, 1847. A few taxa resulted to not belong to the South American Sericini fauna, either due to different geographical provenience or due to incorrect systematical placement within Sericini. Two new combinations and one new synonymy are proposed: Neoserica pubescens (Burmeister, 1855), new combination (= Neoserica subsetosa Ahrens Fabrizi, 2016: 121, new synonymy) and Manonychus robustus (Burmeister, 1855), new combination.

Key to Mexican and Central American genera of Acanthocinini (Coleoptera, Cerambycidae, Lamiinae) with erect setae on elytral surface, excluding the Caribbean Islands.

A key for identification of the 34 genera of Acanthocinini with erect setae on the elytra occurring in Mexico and Central America (excluding the Caribbean Islands) is provided. Leptrichillus Gilmour, 1960 is synonymized with Lepturgotrichona Gilmour, 1957, and Leptrichillus minutus Gilmour, 1960 is synonymized with Lepturges stigmaticus Bates, 1881 (currently, Lepturgotrichona stigmatica).

Key to Mexico and Central America genera of Acanthocinini (Coleoptera, Cerambycidae, Lamiinae) without erect setae on elytral surface, excluding the Caribbean Islands.

A key for identification of the 46 genera of Acanthocinini without erect setae on the elytra and which occur in Mexico and Central America is provided. The 46 genera include 809 species of which 302 in Mexico and Central America. Diagnosis for each genus is provided, as well as type-locality and geographical distribution of the type-species.

Key to South American genera of Acanthocinini (Coleoptera, Cerambycidae, Lamiinae) without erect setae on elytra; synonymies, transferences, revalidation, and notes on genera with erect setae on elytra.

A key for identification for the 54 South American genera of Acanthocinini (Cerambycidae, Lamiinae) without erect setae on the elytra is provided. Diagnosis for each genus is provided, as well as type-locality and geographical distribution of the type species, and of the transferred species. Cristurges Gilmour, 1961 is considered a junior synonymy of Lophopoeum Bates, 1863.

On the enigmatic genus Oectropsis Blanchard (Coleoptera, Cerambycidae, Lamiinae): tribal allocation, synonymy, and new species.

The species of the genus Oectropsis Blanchard, 1851 (Cerambycidae, Lamiinae) are exclusively distributed west of the central Andes region (Chile) and were probably isolated due to phenomena caused by the Andes Mountains. Recent taxonomic revisions of the genus revealed that the species do not have the main features of Acanthocinini, the tribe in which this genus is currently allocated. Instead, they share characteristics with Pogonocherini, especially Pogonocherus Dejean, 1821, whose majority of species are distributed in North America.