Hexacylloepus Hinton, 1940 rises again; 18 new species of a neglected genus (Coleoptera: Byrrhoidea: Elmidae)

Abstract

The genus Hexacylloepus extends from the Neotropical region to the southwestern United States of America. At present, 25 species are known from 20 countries, with no new species proposed since 1972. In this paper, we describe and illustrate 18 new species (H. barrae; H. calori; H. casariae; H. froehlichi; H. geiseri; H. grandis; H. iassu; H. keitai; H. maierae; H. manauara; H. metapa; H. phalluspilosus; H. shorti; H. taylorae; H. thoracica; H. tibialis; H. ubirajarai; H. zaninii), from eight countries and give the first records of the genus from Suriname and Guyana.

A revision of Onychelmis Hinton, 1941 (Coleoptera: Elmidae), with description of new species, DNA barcoding and notes on the geography of the genus

“…Numerous recently published descriptions of new species document the high diversity of Elmidae in the Neotropical region (e.g., Manzo & Archangelsky 2015;Passos et al 2015;Čiampor et al 2016;Shepard & Barr 2016;Barr 2018;Martínez-Román et al 2019;Polizei et al 2020), and although our knowledge of the elmid fauna of the tropics improves and interest in riffle beetle taxonomy grows, the information on the real diversity of the family is still far from complete.…”

Spanglerelmis, a new genus of Elmidae (Insecta: Coleoptera) from Brazil with new species and biological notes

“…The knowledge of Neotropical Elmidae has increased in recent years with the description of several new species (Polizei & Barclay 2018, 2019a, 2019bLinský et al 2019Linský et al , 2021Polizei et al 2020aPolizei et al , 2020bČiampor et al 2021), and two new genera: Amazonopsis Barr, 2018 from Peru, Venezuela, and French Guiana; and Ictelmis Čiampor, Linský & Čiamporová-Zaťovičová reported from Ecuador. In Brazil, although new species have been regularly described in recent years (Polizei 2018a(Polizei , 2018bAlmeida et al 2020;Polizei et al 2020b;Polizei & Fernandes 2020;Polizei & Hamada 2021), the last genera, Tolmerelmis Hinton, 1972 andTyletelmis (Hinton, 1972), were described approximately 50 years ago.…”

“…Elmidae is one of the most diverse families of aquatic beetles, including approximately 1550 species worldwide in 149 genera (Jäch et al 2016;Polizei et al 2020a). Both larval and adult members of this family are aquatic and more diverse in montane areas of tropical and subtropical regions (Jäch & Balke 2008).…”

“…Thus, it is highly likely that the richness of species of Elmidae within Brazil has been strongly underestimated. Despite this, knowledge has advanced, including the description of new species and the development of taxonomic keys (Fernandes et al 2011;Fernandes & Hamada 2012;Sampaio et al 2012;Barbosa et al 2013;Ferreira-Jr et al 2014;Passos et al 2015;Polizei 2018aPolizei , 2018bPolizei & Barclay 2018, 2019a, 2019bLinský et al 2019;Almeida et al 2020;Polizei et al 2020aPolizei et al , 2020bPolizei & Fernandes 2020).…”

Aquatic beetle diversity from Volcán Tacaná, Mexico: altitudinal distribution pattern and biogeographical affinity of the fauna

“…Note. This genus is distributed in the southwestern United States and the Neotropical region, with 25 described species (Jäch et al 2016;Silva-Polizei et al 2020), seven of which are recorded from Mexico (Santiago-Fragoso and Spangler 1995; Jäch et al 2016;Silva-Polizei et al 2020). There are no previous records of altitude for H. metapa, herein the species was collected at levels 1 (670 m), 2 (934 m), 3 (1,126-1,194 m), 4 (river 2, 1,619 m), and 5 (1,763-1,776 m).…”