Liogenys is a neotropical genus widely distributed in South America and characterized by rhizophagous feeding habits. Taxonomy survey of Liogenys from Chile revealed a species complex consisting of L. palpalis, L. obesula and an undescribed morphotype. Morphological data alone are not sufficient to distinguish between them. The three-species hypothesis was tested using phylogenetic and preliminary phylogeographic analyses, as well as unilocus delimitation methods using mitochondrial (COI) and nuclear (ITS2) markers. The tree-based PTP method based on ITS2 considers both L. obesula and the undescribed morphotype to be variants of L. palpalis, a single, polymorphic species. Haplotypes from 12 localities along central Chile revealed four genetically structured populations, with statistical variance (54.34%) only within them. Isolated populations occur in Southern Santiagan Region and coastal desert. There are eight species of Liogenys in Chile. Diagnoses are provided for five species. Liogenys elguetai sp. nov. is described. Five synonyms are proposed for three species. Liogenys pubisternis, a new synonym of L. palpalis, is transferred from Diplotaxis. Lectotypes are provided for four names (L. castaneus, L. grandis, L. pubisternis, and Melolontha palpalis). Liogenys boliviensis is recorded for the first time from Chile and Peru, extending the distribution of Liogenys to northernmost Chile.

The limited temporal completeness and taxonomic accuracy of species lists, made available in a traditional manner in scientific publications, has always represented a problem. These lists are invariably limited to a few taxonomic groups and do not represent up-to-date knowledge of all species and classifications. In this context, the Brazilian megadiverse fauna is no exception, and the Catalogo Taxonomico da Fauna do Brasil (CTFB) (http://fauna.jbrj.gov.br/), made public in 2015, represents a database on biodiversity anchored on a list of valid and expertly recognized scientific names of animals in Brazil. The CTFB is updated in near real time by a team of more than 800 specialists. By January 1, 2024, the CTFB compiled 133,691 nominal species, with 125,138 that were considered valid. Most of the valid species were arthropods (82.3%, with more than 102,000 species) and chordates (7.69%, with over 11,000 species). These taxa were followed by a cluster composed of Mollusca (3,567 species), Platyhelminthes (2,292 species), Annelida (1,833 species), and Nematoda (1,447 species). All remaining groups had less than 1,000 species reported in Brazil, with Cnidaria (831 species), Porifera (628 species), Rotifera (606 species), and Bryozoa (520 species) representing those with more than 500 species. Analysis of the CTFB database can facilitate and direct efforts towards the discovery of new species in Brazil, but it is also fundamental in providing the best available list of valid nominal species to users, including those in science, health, conservation efforts, and any initiative involving animals. The importance of the CTFB is evidenced by the elevated number of citations in the scientific literature in diverse areas of biology, law, anthropology, education, forensic science, and veterinary science, among others.

A new species of Coilodes Westwood, 1846 from the Cordillera Oriental of Colombia, Coilodes soledadae Arias-Buritica, Basilio, and Vaz-de-Mello, new species is described along with a diagnosis, photographs, and discussion of its taxonomic position in the genus. This new species is the fourteenth in the genus. . An update to the identification key to males of Coilodes species is presented.

Two new species, Pseudoazya mirabilis sp. nov. and Pseudoazya massayo sp. nov., both from Northeast Brazil, are described. Pseudoazya is distributed in other localities of Brazil.The new species of Pseudoazya Gordon, 1980 are described based on the external morphology and genitalia of the adults. The genus is distinguished from Azya Mulsant,1850, the only other genus of Azyini, by prosternum with intercoxal process flat, not elevated, and apex of penis bifid.

. A comprehensive overview of Scarabaeoidea in Brazil is provided based on the Taxonomic Catalogue of the Brazilian Fauna (CTFB). Data in CTFB include 2,532 valid species within 345 genera, belonging to 21 subfamilies and 10 families. Those have been described by 272 authors from 1758 to 2023. Among these authors, Moser (1863-1929), and Edgar von Harold (1830-1886) stand out as the most prolific, collectively accounting for approximately 43% of all known Brazilian species of Scarabaeoidea. For taxa occurring in Brazil, we also provide a dichotomous key for use identifying Scarabaeoidea families and subfamilies, along with diagnosis, remarks, and comments on their natural history.

In 2000, Cleide Costa published a paper presenting the state of knowledge of the Neotropical Coleoptera, with a focus on the Brazilian fauna. Twenty-four years later, thanks to the development of the Coleoptera section of the Taxonomic Catalog of the Brazilian Fauna (CTFB - Catalogo Taxonomico da Fauna do Brasil) through the collaboration of 100 coleopterists from all over the globe, we can build on Costa's work and present an updated overview of the state of knowledge of the beetles from Brazil. There are currently 35,699 species in 4,958 genera and 116 families known to occur in the country, including representatives of all extant suborders and superfamilies. Our data show that the Brazilian beetle fauna is the richest on the planet, concentrating 9% of the world species diversity, with some estimates accounting to up to 15% of the global total. The most diverse family in numbers of genera is Cerambycidae (1,056 genera), while in number of species it is Chrysomelidae (6,079 species). Conotrachelus Dejean, 1835 (Curculionidae) is the most species-rich genus, with 570 species. The French entomologist Maurice Pic is the author who has contributed the most to the naming of species recorded from Brazil, with 1,794 valid names in 36 families, whereas the Brazilians Ubirajara R. Martins and Maria Helena M. Galileo are the only ones among the top-ten authors to have named species in the 21(st) century. Currently, approximately 144 new species of Brazilian beetles are described each year, and this average is projected to increase in the next decade to 180 species per year, or about one new Brazilian beetle every two days.

The relationships among the Neotropical Diplotaxini and homology of revised and new taxa are revisited with parsimony analyses based on morphological characters, and probabilistic analyses based on concatenated ITS2 and COI genes. Neotropical Diplotaxini is now composed of five monophyletic genera: Pacuvia, Pachrodema, Homalochilus, Liogenys, and Careocallus gen. nov.. Pseudodiplotaxis is here transferred to incertae sedis of Melolonthinae. Careocallus is the sister genus of Liogenys and is composed of Careocallus tehuelche sp. nov. and Careocallus densicollis sp. nov. Sister phylogenetic relationship between Homalochilus and the rest of genera except Pacuvia is revealed. Homalochilussensu nov. is comprised by Homalochilus punctatostriatus and Homalochilus nigripennis sp. nov. This genus recovered its monophyly by transferring Homalochilus niger to Liogenys, as Liogenys nigercomb. nov. and this name is also synonymized with L. morio. The type species of Homalochilus is emended to be H. punctatostriatus. A neotype (Liogenys morio) and lectotypes (H. punctatostriatus, H. niger) are designated. Dichotomious key to Neotropical Diplotaxini genera and to species of Homalochilus and Careocallus are presented. Sequences and phylogenetic signals for Neotropical melolonthines are reported for the first time.

Hybosoridae comprise five extant subfamilies (Anaidinae, Ceratocanthinae, Hybosorinae, Liparochrinae and Pachyplectrinae). The phylogenetics of Anaidinae and Ceratocanthinae have been analysed previously. This is the first thorough analysis with greater representation of the entire family, especially regarding Hybosorinae. The present study tested the monophyly of Hybosoridae; the monophyly and relationships of its subfamilies and among the genera; and the ‘incertae sedis’ placement of the hybosorid genera Borrochrus and Daimothoracodes and of Orubesa, currently assigned to Scarabaeidae. The matrix consisted of 111 morphological characters and 76 taxa. The monophyly of Hybosoridae and three subfamilies (Anaidinae, Ceratocanthinae and Liparochrinae) was supported. Few changes were necessary to recover the monophyly of Hybosorinae and Pachyplectrinae: Brenskea is transferred from Pachyplectrinae to Hybosorinae, and Borrochrus and Daimothoracodes are allocated to Pachyplectrinae. Hybosorinae include two paraphyletic genera: Apalonychus and Hybosorus. To recover their monophyly, two monotypic genera were synonymized: Hapalonychoides is now a junior subjective synonym of Apalonychus (Apalonychus similis comb. nov.) and Hybosoroides a junior subjective synonym of Hybosorus (Hybosorus alluaudi comb. nov.). Orubesa is more closely related to Ochodaeidae than to Hybosoridae.

Coilodes Westwood, 1846 is a Neotropical genus of Hybosorinae. Despite being a morphologically homogeneous genus, it presents a great deal of intraspecific variation, especially with reference to the colour of integuments. This makes identification of species even more difficult, since the majority of original descriptions present the colour as the main diagnostic character. To solve this problem, the first taxonomic revision of Coilodes is presented. The genus now comprises 13 species. Redescriptions of C. castaneus Westwood, 1846, C. fumipennis Arrow, 1909, C. humeralis (Mannerheim, 1829), C. niger (Mannerheim, 1829), C. ovalis Robinson, 1948, C. parvulus Westwood, 1846, and C. punctipennis Arrow, 1909 are presented. Coilodes niger (Mannerheim, 1829) has its status revalidated and three new synonyms are proposed: C. gibbus (Perty, 1830) and C. chilensis Westwood, 1846 with C. humeralis, and C. nigripennis Arrow, 1903 with C. castaneus. Biological and geographical distribution data are expanded. Lectotypes are designated for C. humeralis and C. niger. Six new species are described: C. bezerrai Basílio & Vaz-de-Mello sp. nov., C. edeiltae Basílio & Vaz-de-Mello sp. nov., C. lunae Basílio & Vaz-de-Mello sp. nov., C. mayae Basílio & Vaz-de-Mello sp. nov., C. ravii Basílio & Vaz-de-Mello sp. nov., and C. skelleyi Basílio & Vaz-de-Mello sp. nov. An identification key for the males of the species is presented.

Among the 26 Hybosorinae genera, seven are present exclusively in the Neotropical region. However, Hybosorinae from the New World have been less studied. One new genus and new species collected in Brazil is herein described to this subfamily. The genus is recognizable by the following combination of characters: labium with semicircular mentum; mandibles with lateral projection excavated, separated in the middle by longitudinal carina, inner side sheltering the labrum; antennae with nine antenomeres; scutellar shield with strong punctures at the proximal half; elytra with single rows formed by punctures; and protibia without well-defined denticles.

The biodiversity of northern South American and Central American Liogenys Guérin-Méneville, 1831 (Coleoptera: Scarabaeidae: Melolonthinae: Diplotaxini) is reviewed. Four new species are described: L. clipeosetosa Cherman, new species; L. genieri Smith & Cherman, new species; L. granadina Cherman, new species; and L. schneiderae Cherman, new species. The male of L. quadridens (Fabricius, 1798) and the female of L. quadridentata Blanchard, 1851 are described for the first time. Liogenys gebieni Moser, 1921 is a new junior subjective synonym of L. macropelma Bates, 1887. The northernmost record of Liogenys is emended to Trinidad and Tobago for L. granadina Cherman, new species and L. schneiderae new species. Diplotaxis puberea cuprascens (Bates, 1887) new combination, Diplotaxis puberea puberea (Bates, 1887) new combination, and Diplotaxis pubisternis (Bates, 1887) new combination are all transferred from Liogenys to Diplotaxis Kirby, 1837. Lectotypes are designated for Liogenys gebieni Moser, 1921; Melolontha quadridens Fabricius, 1798; and Liogenys quadridentatus Blanchard, 1851. An identification key to northern South American Liogenys is presented.

A taxonomic revision of the Liogenys Guérin-Méneville, 1831 (Coleoptera: Scarabaeidae: Melolonthinae: Diplotaxini) from the Chacoan Biogeographical Province is presented. Liogenys now includes 92 species, including four new species described here: L. neoforcipata Cherman, new species; L. foveata Cherman, new species; L. isotarsis Cherman, new species; and L. truncata Cherman, new species; and the female of L. tarsalis Moser is described for the first time. Six new synonymies are proposed: L. denticulata Moser, 1918 is a new synonym of L. denticeps Blanchard, 1851; L. ophtalmica Frey, 1973 is a new synonym of L. bidenticeps Moser, 1919; L. mendozana incisa Frey, 1969 is a new synonym of L. mendozana Moser, 1918; L. flavicollis Blanchard, 1851 and L. fulvescens Blanchard, 1851 are new synonyms of L. pallens Blanchard, 1851; and L. densicollis Moser, 1921 is a new synonym of L. opacicollis Fairmaire, 1892. Liogenys cribricollis Moser, 1921 species status is revalidated from its synonymy with L. densicollis. A neotype is designated for Liogenys mendozana incisa Frey, 1969, as well as lectotypes for: L. bruchi Moser, 1924; L. cribricollis, L. denticulata, L. denticeps, L. fulvescens, L. latitarsis Moser, 1918; L. mendozana Moser, 1918; L. obscura Blanchard, 1851; L. opacicollis; and L. pallens. Redescriptions and/or diagnoses and updated geographical distributions are provided for 16 species. Six species previously known only from Argentina have their distribution expanded to Bolivia (L. mendozana; L. opacicollis; L. rectangula Frey, 1969), Paraguay (L. nigrofusca Moser, 1918; L. pallens), or to both of these countries (L. latitarsis).

Among the predatory ladybird beetles (Coccinellidae: Coleoptera), members of the Coccinellini, predators of aphids and psyllids, stand out. Although the beneficial status of these beetles has been acknowledged by biological control researchers, there are no keys or detailed studies on the immature stages of South American Coccinellidae, especially Coccinellini. We provide descriptions and illustrations of the immatures and adults of major predatory Coccinellini species in southern Brazil along with an identification key for fourth instar larvae and pupae. The following species are included: Cycloneda sanguinea (Linnaeus, 1763), Eriopis connexa (Germar, 1824), Harmonia axyridis (Pallas, 1773), Hippodamia convergens Guérin-Méneville, 1842 and Olla v-nigrum (Mulsant, 1866). The morphological study, which included the use of scanning electron microscopy, revealed new characters such as the type of tarsal claws, spiracles, chalazae, parascoli and strumae. The identification key provided here may be useful in biological control programs.