Matrix-based key to the click beetle genera of Canada and USA with a summary of habitat use (Coleoptera, Elateridae).

The Elateridae, or click beetles are abundant and diverse in most terrestrial ecosystems in North America, acting as plant pests and filling many other ecological roles. The 112 genera of Elateridae Leach, 1815, or click beetles, known from Canada and USA are included in a first comprehensive digital interactive key to adults. A link to an online peer-reviewed LUCID key to elaterid genera and downloadable LUCID files are provided. Diagnostic morphological summaries using information from the 61 characters and 158 character states of the matrix key are presented for all genera. A table summarizes current understanding of habitat use by all elaterid genera in Canada and USA from literature, collections, citizen science, and our own observations. Diversity of elaterid genera was high throughout warm and cool temperate regions, especially in mountainous areas and mesic woodlands. Larvae of most genera were associated with soil, litter and decaying wood.

Limoniic Acid and Its Analog as Trap Lures for Pest Limonius Species (Coleoptera: Elateridae) in North America.

Four species of Limonius wireworms (Coleoptera: Elateridae), L. californicus, L. canus, L. infuscatus and L. agonus, are serious crop pests in North America. Limoniic acid, (E)-4-ethyloct-4-enoic acid, has been reported as a sex pheromone component of female L. californicus and L. canus, and a sex attractant for male L. infuscatus. In the same study, both limoniic acid and the analog (E)-5-ethyloct-4-enoic acid were highly attractive in field experiments. Moreover, six carboxylic acids in headspace volatiles of Limonius females elicited responses from male antennae but were not tested for behavioral activity. Here, we report trap catch data of Limonius spp. obtained in field experiments at 27 sites across North America. All four Limonius species were attracted to limoniic acid and to the analog but not to the carboxylic acids. Adding these carboxylic acids to limoniic acid, or to the analog, reduced its attractiveness. In dose-response studies, trap lures containing 0.4 mg or 4 mg of limoniic acid afforded large captures of L. californicus and L. infuscatus. Neither limoniic acid nor the analog were deterrent to other elaterid pest species. The broad attractiveness of limoniic acid to Limonius spp., and its non-deterrent effect on heterogeners, may facilitate the development of generic pheromone-based monitoring and management tools for multiple click beetle species.

Description of a new species of Platyparadonus Etzler and Ivie, 2019 (Coleoptera: Elateridae), with an updated key to species.

A new species of the genus Platyparadonus Etzler Ivie, 2019, is described from St. John (United States Virgin Islands). Taxonomic and diagnostic remarks are provided along with a map of distribution and a key to the species. The misinterpretation of female paratypes belonging to P. marleyi Etzler Ivie, 2019 from St. John is also clarified.

Review of the genus Paradonus Stibick, 1971 (Elateridae: Negastriinae), with three new North American species.

Three new North American species of Paradonus Stibick are described: Paradonus gallatinensis new species, Paradonus gustafsoni new species and Paradonus stibicki new species is described for specimens formerly called Paradonus pectoralis sensu Stibick, 1991. The type species of the genus, Paradonus pectoralis Say, 1839 is redefined, and the Holotype of Paradonus olivereae Stibick, 1991 is designated as the Neotype of P. pectoralis, a common, widespread species. The genus is redescribed, a checklist of species is included, and notes on the described species north of Mexico are given. Hypnoidus guatemalensis Champion, 1895 is removed from the genus and placed in Zorochros Thompson, 1858 as Zorochros guatemalensis (Champion, 1895) new combination. A key to all described species north of Mexico is provided, along with illustrations of characters used in identifying species.

Generic Reclassification of Limonius Eschscholtz, 1829 (Elateridae: Dendrometrinae) sensu Candèze 1860 of the World.

The genus Limonius Eschscholtz, 1829 was last treated as a whole by Candèze (1860). Since then, members have been placed in eight other genera: Cidnopus Thomson, 1859; Gambrinus LeConte, 1853; Elathous Reitter, 1890; Kibunea Kishii, 1966; Limoniscus Reitter, 1905; Nothodes LeConte, 1861; Pheletes Kiesenwetter, 1858; and Solskyana Dolin, 1978. Based on the examination of adult and larval characters, five genera are recognized: Elathous Reitter, 1890; Gambrinus LeConte, 1853; Limonius Eschscholtz, 1829; Pheletes Kiesenwetter, 1858; and Tetralimonius new genus. Limoniscus Reitter, 1905 and Sichuanelater Platia and Gudenzi, 2006 are new synonymies of Gambrinus LeConte, 1853; Micrathous Lane, 1971, Neoathousius Schimmel and Platia, 1991 and Solskyana Dolin, 1978 are all new synonymies of Limonius. A total of 84 new combinations are proposed: Nearctic: Elathous huguenini (Van Dyke, 1932) new combination; Gambrinus angulatus (Motschulsky, 1859) new combination; Gambrinus bicolor (Van Dyke, 1932) new combination; Gambrinus clypeatus (Motschulsky, 1859) new combination; Gambrinus confusus (LeConte, 1853) new combination; Gambrinus cribriceps (Van Dyke, 1943) new combination; Gambrinus crotchii (Horn, 1872) new combination; Gambrinus flavomarginatus (Knull, 1938) new combination; Gambrinus fulvipilis (Candèze, 1860) new combination; Gambrinus griseus (Beauvois, 1805) new combination; Gambrinus humidus (Lane, 1941) new combination; Gambrinus interstitialis (Melsheimer, 1846) new combination; Gambrinus lanchesteri (Lane, 1941) new combination; Gambrinus meridianus (Knull, 1947) new combination; Gambrinus mirus (LeConte, 1853) new combination; Gambrinus norahae (Al Dhafer, 2009) new combination; Gambrinus olentangyi (Knull, 1947) new combination; Gambrinus plebejus (Say, 1825) new combination; Gambrinus propexus (Candèze, 1860) new combination; Gambrinus rudis (Brown, 1933) new combination; Gambrinus rufihumeralis (Lane, 1941) new combination; Gambrinus seminudus (Van Dyke, 1932) new combination; Gambrinus shircki (Lane, 1965) new combination; Gambrinus sinuifrons (Fall, 1907) new combination; Gambrinus snakensis (Lane, 1965) new combination; Gambrinus stigma (Herbst, 1806) new combination; Gambrinus pictus (Van Dyke, 1932) new combination; Gambrinus ulkei (Horn, 1871) new combination; Gambrinus ursinus (Van Dyke, 1932) new combination; Gambrinus venablesi (Wickham, 1913) new combination; Limonius brevis (Van Dyke, 1932) new combination; Limonius sordidus (Van Dyke, 1932) new combination; Pheletes lecontei (Lane, 1971) new combination; Tetralimonius definitus (Ziegler, 1845) new combination; Tetralimonius humeralis (Candèze, 1860) new combination; Tetralimonius maculicollis (Motschulsky, 1860) new combination; Tetralimonius nimbatus (Say, 1825) new combination; Tetralimonius ornatulus (LeConte, 1857) new combination. Palearctic: Gambrinus elegans (Buysson, 1891) new combination; Gambrinus gibbosus (Platia and Gudenzi, 2006) new combination. Gambrinus henanensis (Schimmel, 2006) new combination; Gambrinus hinakurai (Kishii, 1998) new combination; Gambrinus katoi (Kishii, 2002) new combination; Gambrinus kawaharai (Kishii, 2002) new combination; Gambrinus kucerai (Schimmel, 2006) new combination; Gambrinus nanshanensis (Arimoto and Hiramatsu, 2013) new combination; Gambrinus naomii (Kishii, 1997) new combination; Gambrinus shaanxiensis (Schimmel, 2006) new combination; Gambrinus suturalis (Gebler, 1844) new combination; Gambrinus takabai (Kishii, 1997) new combination; Gambrinus violaceus (Müller, 1821) new combination; Gambrinus wittmeri (Chassain, 1998) new combination; Gambrinus yamato (Kishii, 1998) new combination; Gambrinus yujii (Arimoto, 2013) new combination; Gambrinus zhejiangensis (Schimmel, 2015) new combination; Limonius brancuccii (Schimmel and Platia, 1991) new combination; Limonius decorus (Gurjeva, 1975) new combination; Limonius exiguus (Schimmel and Platia, 1991) new combination; Limonius hartmanni (Schimmel, 1998) new combination; Limonius hiermeieri (Schimmel and Platia, 1991) new combination; Limonius hirtus (Dolin, 1978) new combination; Limonius hubeiensis (Kishii and Jiang, 1996) new combination; Limonius kubani (Schimmel, 1996) new combination; Limonius loebli (Schimmel and Platia, 1991) new combination; Limonius longicornis (Schimmel and Platia, 1991) new combination; Limonius macedonicus (Cate and Platia, 1989) new combination; Limonius marginellus brusteli (Leseigneur, 2004) new combination; Limonius manaliensis (Schimmel and Platia, 1991) new combination; Limonius miandamensis (Schimmel and Platia, 1991) new combination; Limonius minusculus (Schimmel and Platia, 1991) new combination; Limonius nigronitidus (Han and Lee, 2012) new combination; Limonius platiai (Mertlik, 1996) new combination; Limonius pseudopilosus (Platia and Gudenzi 1985) new combination; Limonius recticornis (Schimmel and Platia, 1991) new combination; Limonius riesei (Platia, 1988) new combination; Limonius rusticus (Schimmel and Platia, 1991) new combination; Limonius schurmanni (Platia and Gudenzi, 1998) new combination; Limonius sinensis (Schimmel and Platia, 1994) new combination; Limonius singularis (Schimmeland Platia, 1991) new combination; Limonius stapfi (Schimmel, 2007) new combination; Limonius turcicus (Platia, 2004) new combination; Limonius wittmeri (Schimmel and Platia, 1991) new combination; Tetralimonius quercus (Olivier, 1790) new combination; Tetralimonius reitteri (Gurjeva, 1976) new combination. The following 12 North American species are removed from synonymy and recognized as valid species: Gambrinus interstitialis (Melsheimer, 1846) status resurrected; Gambrinus propexus (Candèze, 1860) status resurrected; Gambrinus shircki (Lane, 1965) status resurrected; Gambrinus snakensis (Lane, 1965) status resurrected; Gambrinus ulkei (Horn, 1871) status resurrected; Limonius anceps LeConte, 1853 status resurrected; Limonius dubitans LeConte, 1853 status resurrected; Limonius infuscatus Motschulsky, 1859 status resurrected; Limonius pilosulus Candèze, 1891 status resurrected; Limonis semianeus LeConte, 1853 status resurrected. Tetralimonius humeralis (Candèze, 1860) status resurrected; Tetralimonius maculicollis (Motschulsky, 1860) status resurrected. New replacement names are proposed for three homynyms: Limonius schimmeli Etzler new name for Neoathousius ferrugineus Schimmel and Platia, 1991; Elathous malatyanus Etzler new name for Elathous bicolor Platia, 2010, not Elathous bicolor (LeConte, 1853); and Microdesmes carteri Etzler new name for Limonius angulatus Carter, 1939 (= Microdesmes angulatus). Limonius kondratieffi Al Dhafer, 2009 is a new synonymy of Elathous bicolor (LeConte, 1853). A key to genera, generic descriptions, notes on species, and definitions of important characters are provided.

DNA barcoding to improve the species-level management of wireworms (Coleoptera: Elateridae).

Economically important species of wireworms (Coleoptera: Elateridae) were successfully associated with adults using cytochrome oxidase I (COI) barcoding, proving the usefulness of this technique to associate life stages in taxonomically difficult pest groups. Previously unrecognized and morphologically difficult, even indistinguishable, pest larvae were shown to be identifiable using this technique. This is a critical step toward discovering effective species-based integrated pest management strategies for this resurgent pest group following the loss of Lindane seed treatments. Three new adult-larval associations were discovered for Hadromorphus callidus (Brown), Hemicrepidius carbonatus (LeConte) and Metanomus insidiosus (LeConte). Hypnoidus bicolor (Eschscholtz) was shown to comprise multiple divergent lineages at a level usually considered different species, indicating that the population structure of some pest species requires more investigation. The status of the prairie grain wireworm, Selatosomus destructor (Brown), as a full species or as a subspecies of Selatosomus aeripennis (Kirby) is called into question.