Towards a comprehensive taxonomic revision of the Neotropical dung beetle subgenus Deltochilum (Deltohyboma) Lane, 1946 (Coleoptera: Scarabaeidae: Scarabaeinae): Division into species-groups

Abstract

Deltochilum Eschscholtz, 1822 is perhaps the most speciose genus of the tribe Deltochilini sensu Tarasov & Dimitrov (2016) (Scarabaeidae: Scarabaeinae) and has been traditionally divided into eight subgenera. Among them, the subgenus Deltohyboma Lane, 1946, is the most speciose with 47 species, five of which are described here (D. genieri sp. nov., D. gilli sp. nov., D. susanae sp. nov., D. bolivariensis sp. nov. and D. inesae sp. nov.), and at least 165 species still undescribed. Due to the large number of species, and for practical purposes, the subgenus is here divided into 19 species-groups, with D. inesae sp. nov. left as incertae sedis. This division into species-groups will help in the reliable identification of species and will aid in the completion of the revision of subgenus. This report is the first part of the taxonomic revision of the subgenus Deltohyboma; it is based on the examination of all type specimens and almost 9,800 specimens of which approximately 1,200, mostly males, had their genitalia studied. The 19 species-groups recognized here are based mainly on characters described for the first time for Deltohyboma, namely, the state of a) the anterior margin of the clypeus (between the clypeal teeth), b) the internal margin of hypomera, c) the ventral face of the protibia, d) the posterior margin of the metafemur, and e) several new characters resulting from the first detailed study of the aedeagus and the endophallus of the group. Diagnosis, description, geographic distribution, composition and identifications keys (for males as well as males and females) for the species-groups are provided.

Taxonomic identification accuracy from BOLD and GenBank databases using over a thousand insect DNA barcodes from Colombia

“…In contrast, the identification was incorrect for some species with restricted distributions in Colombia such as Canthon arcabuquensis , Dichotomius andresi , Uroxys cuprescens , and Deltochilum susanae , the latest was first identified as the morphospecies Deltochilum sp. 12H [ 42 ] and later described as a new species [ 43 ] or species with Andean distributions as in Dichotomius protectus , Eurysternus marmoreus and Ontherus brevicollis [ 44 – 49 ]. In the case of Scarabaeinae dung beetles, the barcode results helped to confirm at least five species that were assigned as morphospecies in the dung beetles of Colombia “Reference Collection” hosted at of IAVH Entomological Collection.…”

Taxonomic identification accuracy from BOLD and GenBank databases using over a thousand insect barcodes from Colombia

“…In contrast, the identification was incorrect for some species with restricted distributions in Colombia such as Canthon arcabuquensis, Dichotomius andresi, Uroxys cuprescens, and Deltochilum susanae, the latest was first identified as the morphospecies Deltochilum sp. 12H [39] and later described as a new species [40] or species with Andean distributions as in Dichotomius protectus, Eurysternus marmoreus and Ontherus brevicollis [41][42][43][44][45][46]. In the case of Scarabaeinae dung beetles, the barcode results helped to confirm at least five species that were assigned as morphospecies in the dung beetles of Colombia "Reference Collection" hosted at of IAVH Entomological Collection.…”

Taxonomic revision of the Deltohyboma Lane, 1946 gilli species group (Coleoptera: Scarabaeidae: Scarabaeinae: Deltochilum)

“…The dung beetles (Scarabaeinae) of the genus Deltochilum Eschscholtz, 1822 are widely distributed in the Neotropical region, comprising 114 valid species (including four new species described here). Deltochilum is divided into eight subgenera (Génier 2012;González-Alvarado et al 2019;González-Alvarado & Vaz-de-Mello 2014, 2021Silva et al 2015). Within those subgenera, two are monospecific Euhyboma Kolbe, 1893 andRubrohyboma Paulian, 1938; one has two species Parahyboma Paulian, 1938; three have been taxonomically revised Aganhyboma Kolbe, 1893, Deltochilum s. str.…”

“…Within those subgenera, two are monospecific Euhyboma Kolbe, 1893 andRubrohyboma Paulian, 1938; one has two species Parahyboma Paulian, 1938; three have been taxonomically revised Aganhyboma Kolbe, 1893, Deltochilum s. str. and Hybomidium Shipp, 1897 (Génier 2012;The methodology as well as the terminology, pertaining to the external morphology and male genitalia follow those described in González-Alvarado & Vaz-de-Mello (2021). The material examined was prepared following the Material Citations Formatting Guide provided by this journal.…”

“…A complete description of the subgenus Deltohyboma and a short description of the gilli species group were provided in González-Alvarado & Vaz-de-Mello (2021); here, a more comprehensive description of the species group is presented, in which the characters shared by all species are described and are not repeated in the species descriptions. For species diagnoses, each species is compared to species belonging to the gilli species group only.…”