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

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.

The Neotropical genus Portelmis Sanderson, 1953 (Coleoptera: Elmidae): three new species, new records and updated key.

Elmidae is one of the most diverse families of aquatic beetles, with more than 1500 species in 151 genera. The Neotropical genus Portelmis formerly comprised five species known from Central and northern South America, divided into two species groups. Three new Brazilian species from the nevermanni group are described and illustrated here: Portelmis vanini sp. nov., Portelmis krolowi sp. nov. and Portelmis fusariae sp. nov. New species records for the North, Central-West and Southeast of Brazil are presented. We also provide first SEM images and an updated key for Portelmis species.

Sensibilidad de Elmidae (Insecta: Coleoptera) a la perturbación del hábitat y la calidad fisicoquímica del agua en ambientes lóticos de los Andes colombianos / Sensitivity of Elmidae (Insecta: Coleoptera) to habitat disturbance and physicochemical water quality in lotic environments of the Colombian Andes

Introducción: Los élmidos son organismos acuáticos frecuentemente asociados con aguas corrientes, limpias y bien oxigenadas. Sin embargo, algunos géneros de esta familia también se encuentran en aguas moderadamente contaminadas, lo cual puede ser un reflejo de su tolerancia a algún grado de deterioro del hábitat. Objetivo: Determinar la sensibilidad o tolerancia a la contaminación y los principales factores que influyen en la presencia y composición taxonómica de Elmidae en microcuencas colombianas. Métodos: Se muestrearon 60 localidades entre 450 y 4 000 msnm, principalmente en la región Andina, los muestreos se realizaron entre 2002 y 2013 con 70 eventos no simultáneos en cinco zonas. En un transecto de 100 m, se registraron datos físico-químicos, bacteriológicos y de calidad del hábitat (ICH), se hicieron arrastres con red D y Surber, y se determinaron los géneros de Elmidae. Se realizó un Análisis de Correspondencia Canónica entre las variables ambientales y la composición de Elmidae, las relaciones significativas se confirmaron con una prueba de Mantel y se realizó una prueba Mantel parcial incluyendo la ubicación geográfica como tercera matriz. Se calcularon los Índices de Contaminación ICOs y de Calidad de Agua ICA-FSN y se definieron intervalos de aparición de géneros para variables ambientales e índices. Para obtener las significancias estadísticas, se realizaron Análisis de Varianza ANOVA, pruebas t de Student y Modelos Lineales Generalizados MLG con distribución Poisson. Resultados: Se encontraron 22 géneros y 15 especies que representan el 78.5 % de la riqueza nacional conocida. Tyletelmis y las especies Gyrelmis pusio, G. simplex, Xenelmis sandersoni, X. leechi, X. granatoides y X. teres, corresponden a nuevos registros para Colombia. Los principales factores que influyeron en la riqueza y composición de Elmidae fueron: saturación de oxígeno, deposición de sedimentos,sólidossuspendidos, disponibilidad de sustratos, altura, ubicación geográfica, conductividad, alcalinidad, turbidez, nitratos, nitrógeno amoniacal y fósforo. Conclusiones: Los géneros de Elmidae difieren en su tolerancia a la contaminación y, por lo tanto, no pueden ser clasificados bajo el mismo grado de sensibilidad. Esta información puede ser útil para la clasificación de los géneros de Elmidae de acuerdo con su sensibilidad a los cambios en las condiciones ambientales y la degradación del hábitat, lo cual será un primer paso para la incorporación en un índice biótico de calidad de agua adaptado para las condiciones locales o el ajuste de los índices preexistentes.

Introduction: Riffle beetles are aquatic organisms frequently associated with well-oxygenated clean running water. However, some genera of Elmidae can also be found in moderately polluted streams proving their tolerance to certain degree of habitat degradation. Objective: To determine the pollution sensitivity and tolerance of each genus of Elmidae in Colombian streams, and the main factors that influence its presence and taxonomic composition. Methods: Sixty locations between 450 and 4 000 m.a.s.l. were sampled, mainly in the Andean Region of Colombia. Collection was carried out between 2002 and 2013 with 70 non-simultaneous events in five zones. In a 100 m transect, physicochemical, bacteriological and environmental quality information was recorded. Samples of Elmidae were collected with D and Surber nets and determined taxonomically. A Canonical Correspondence Analysis of the Elmidae assembly and environmental data was carried out, significant relationships were confirmed with a Mantel test and a partial Mantel test was carried out including the geographic location as the third matrix. The Pollution (ICO) and Water Quality (ICA-NSF) Indices were calculated, and the occurrence intervals by genus were plotted for environmental variables and indices. Analysis of Variance ANOVA, Student's t-test and Generalized Linear Models GLM with Poisson distribution, were calculated in order to establish the significance of the results. Results: Twenty-two genera and 15 species were found in the evaluated streams; which represent 78.5 % of known national generic richness. Tyletelmis and the species Gyrelmispusio, G. simplex, Xenelmis sandersoni, X. leechi, X. granatoides and X. teres correspond to new records for Colombia. The most important factors influencing the presence and composition of Elmidae were: oxygen saturation, sediment deposition, suspended solids, epifaunal substrate availability, altitude and geographic location, conductivity, turbidity, alkalinity, nitrates, ammonia nitrogen and phosphorus. Conclusions: The genera of Elmidae differ in their tolerance to contamination and therefore cannot be classified in the same degree of sensitivity. This information can be useful for classifying genera of Elmidae according to their sensitivity to changes in environmental conditions and habitat degradation, which will be a first step to incorporate Elmidae in water quality biotic indices adapted to local conditions or to adjust preexisting indices.

Notes on Stenhelmoides and description of the true male genitalia of S. strictifrons Grouvelle, 1908 (Coleoptera: Elmidae) / Notas sobre Stenhelmoides e descrição da genitália verdadeira do macho de S. strictifrons Grouvelle, 1908 (Coleoptera: Elmidae)

The genus Stenhelmoides comprises 15 species spread over all Central and South America and its greatest species richness is clearly associated with Amazonian regions. Based on examination of type specimens and additional material, we describe and illustrate the true male genitalia of Stenhelmoides strictifrons, which had until now been incorrectly illustrated in the literature. We also report new records of the genus Stenhelmoides from Brazil and Guyana. In addition to pictures of the species habitus, we provide pictures of the type specimens of Stenhelmoides grandis, S. grouvellei, S. guyanensis; S. strictifrons and S. submaculus. Based on the International Code of Zoological Nomenclature, we recognize additional paralectotypes for S. guyanensis and for S. grouvellei(AU)

O gênero Stenhelmoides compreende 15 espécies espalhadas por toda a América Central e do Sul e sua maior riqueza de espécies está claramente relacionada às regiões amazônicas. Com base no estudo de espécimes-tipo e material adicional, nós descrevemos e ilustramos a genitália verdadeira do macho de Stenhelmoides strictifrons, que, até então, estava representada de maneira equivocada na literatura. Nós também reportamos novos registros de Stenhelmoides para o Brasil e Guiana. Além de imagens do habitus das espécies, fornecemos fotografias dos espécimes-tipo de Stenhelmoides grandis, S. grouvellei, S. guyanensis; S. strictifrons e S. submaculus. De acordo com as regras e recomendações do Código Internacional de Nomenclatura Zoológica, reconhecemos paralectótipos adicionais das espécies S. guyanensis e S. grouvellei(AU)

The genus Cylloepus Erichson, 1847 (Coleoptera: Elmidae: Elminae) new species and combinations.

Elmidae is one of the most diverse families of aquatic beetles, with more than 1500 species in 148 genera. Cylloepus is the genus with the most species in Americas, with 52 species and 2 subspecies currently known. The genus is easily recognised by external morphology; body elongate, pronotum with a longitudinal impression on the disc and elytra striate and punctate. In this paper, based on the study of several international reference collections, we propose two new combinations, and describe two new species of Cylloepus (C. bispoi sp. nov. and C. segurae sp. nov.) from Ecuador and Bolivia.

First records of the genera Neocylloepus and Pilielmis (Coleoptera: Elmidae: Elminae) from Venezuela, with the description of Pilielmis shepardi sp. nov.

Neocylloepus Brown, 1970 and Pilielmis Hinton, 1971 are Neotropical genera of riffle beetles, mainly distributed in Central America and the north of South America. These genera are here reported for the first time from Venezuela, and a new species, Pilielmis shepardi sp. nov. is described and illustrated. The type material is housed in Museu de Zoologia da Universidade de São Paulo, São Paulo, Brazil (MZSP), Natural History Museum, London, UK (BMNH), Museo del Instituto de Zoología Agrícola, Maracay, Venezuela (MIZA), Michael A. Ivie Collection, Bozeman, Montana, USA (MAIC), and National Museum of Natural History, Smithsonian Institution, Washington DC, USA (USNM).

Four new species of Hexanchorus Sharp from Ecuador (Coleoptera, Elmidae) with DNA barcoding and notes on the distribution of the genus.

The riffle beetle genus Hexanchorus Sharp, 1882 is distributed from Mexico to Argentina, forming an important component of the freshwater invertebrate fauna of Latin America. With 21 described species, Hexanchorus represents one of the most speciose Larainae genera, but its real diversity is likely much higher. We analysed material from a relatively small area in Ecuador, resulting in the first record of H.cordillierae for Ecuador and discovery of four new species and one subspecies: Hexanchorusvirilis sp. n., Hexanchorusrostratus sp. n., Hexanchorusshepardi sp. n., Hexanchorusonorei sp. n. and Hexanchorusonoreisagittatus ssp. n. For delimiting and characterizing species, both morphological and molecular (mtCOI DNA barcodes) data were used. A distribution map of Hexanchorus species is provided based on published records.

A new species and a key for the Brazilian species of the genus Heterelmis Sharp, 1882 (Coleoptera: Elmidae, Elminae)

Heterelmis Sharp, 1882, comprises 22 species and subspecies with 3 species assigned to Brazil so far. Here the forth species, Heterelmis debilis sp. nov. from Brazil, is described and illustrated. The type material is deposited in the Museum of Zoology of the University of São Paulo, São Paulo, Brazil (MZSP) and Natural History Museum, London, UK (NHMUK). Additionally, an identification key with distributional data for Brazilian species is proposed.

A new species and a key for the Brazilian species of the genus Heterelmis Sharp, 1882 (Coleoptera: Elmidae, Elminae)

Heterelmis Sharp, 1882, comprises 22 species and subspecies with 3 species assigned to Brazil so far. Here the forth species, Heterelmis debilis sp. nov. from Brazil, is described and illustrated. The type material is deposited in the Museum of Zoology of the University of São Paulo, São Paulo, Brazil (MZSP) and Natural History Museum, London, UK (NHMUK). Additionally, an identification key with distributional data for Brazilian species is proposed.(AU)

Description of the mature larva of Austrolimnius nyctelioides (Germain, 1892) and A. elatus Hinton, 1941 (Coleoptera: Elmidae).

Mature larvae of two species of the riffle beetle genus Austrolimnius Carter & Zeck, 1929 are described and illustrated for the first time: Austrolimnius nyctelioides (Germain, 1892) and A. elatus Hinton, 1941. A larval diagnosis for the genus is presented and both larvae are compared with each other and with the previously described larva of A. mucubajiensis Gómez & Bello, 2006. Comments on the species' habitats are included.

Taxonomic key for the genera of Elmidae (Coleoptera, Byrrhoidea) occurring in Goiás State, Brazil, including new records and distributional notes

A taxonomic key for the genera of Elmidae (Coleoptera, Byrrhoidea) occurring in Goiás State, Brazil, including new records and distributional notes. Despite their great diversity and high abundance in Neotropical aquatic environments, the fauna of Elmidae remains practically unknown in some areas and even entire biomes in this region. In this work we bring, for the first time, faunistic data for the Elmidae of central Brazil. The aim of this work was to inventory the Elmidae fauna in central, southwestern and southeastern Goiás State, Brazil and to produce a taxonomic key, at genus level, for adults from the studied region. The taxonomic key presented herein offers means for the identification of all the 13 genera known to occur in Goiás, 11 of them being new records for the State. Moreover, the number of named species registered for Goiás increased from one to nine.

Elmidae (Coleoptera, Byrrhoidea) larvae in the state of São Paulo, Brazil: Identification key, new records and distribution.

The family Elmidae Curtis, 1830 has cosmopolitan distribution and most species inhabit riffles on streams and rivers, hence the name "riffle beetle". In recent years, this family has been featured in papers addressing the assessment and environmental monitoring of water quality. In Brazil, studies on the family remain scarce and the present investigation is a pioneering study in the state of São Paulo. This study aims to propose a taxonomic key for the identification of larvae of Elmidae genera known to occur in the State, as well as to report new records and the distribution of these genera. The material analyzed was collected from various locations in each of 15 drainage basins from 2005 to 2010. The identification key includes 12 genera (Austrolimnius Carter & Zeck, 1929, Heterelmis Sharp, 1882, Hexacylloepus Hinton, 1940, Hexanchorus Sharp, 1882, Huleechius Brown, 1981, Macrelmis Motschulsky, 1859, Microcylloepus Hinton, 1935, Neoelmis Musgrave, 1935, Phanocerus Sharp, 1882, Potamophilops Grouvelle, 1896, Stegoelmis Hinton, 1939 and Xenelmis Hinton, 1936) known in Brazil as well as three morphotypes designated herein as Genus A, Genus M and Genus X. The genus Hexanchorus is recorded for the first time in the state of São Paulo.