A revision of the neotropical click beetle genera Semiotinus Pjatakowa and Semiotus Eschscholtz (Coleoptera: Elateridae)

The Neotropical click beetle genera Semiotinus and Semiotus are monophyletic groups within the subfamily Campsosterninae. Semiotinus is defined by the connate meso- and metasterna, presence of three membranous tarsal pads, and straight or recurved pronotal margins meeting the hypomera at an acute angle, without sulci. Semiotus is defined by the connate meso- and metasterna, presence of three membranous tarsal pads, and either sulcate, undulate, tuberculate, rounded or incrassate pronotal margins. A cladistic analysis of the genus was carried out using 40 characters from external morphology and male and female genitalia. Apomorphic states were identified using the genus Oistus as an outgroup. The 17 known species of Semiotinus and 82 species of Semiotus are described and keyed. Fifteen species, formerly placed in Semiotus are transferred to the genus Semiotinus , which formerly included only S. banghaasi. Semiotinus maculatus is newly described. Semiotus straminious is designated as a synonym of Semiotinus brevicollis, n. comb.; S. dyptichus and S. subvirescens are designated as synonyms of S. quadricollis, n. comb.; S. juveniles and S. borrei are designated as synonyms of S. fusiformis, n. comb.; S. elegantulus is designated as a synonym of S. trilineatus, n. comb.; S. pulchellus is designated as a synonym of S. quadrivittis , n. comb.; S. staudingeri is designated as a synonym of S. aeneovittatus, n. comb.; Semiotus aliciae, S. angustus, S. catei, S. chassaini, S. clarki, S. colombianus, S. cyrtomaris, S. gibbosus, S. kathleenae, S. kondratieffi, S. lacrimiformis, S. melleus, S. pallicornus, S. perangustus, S. pilosus, S. rileyi, S. rubricollis, S. spinosus, S. trinitensis, S. triplehorni, and S. woodi are newly described. Semiotus superbus reductus is designated as a synonym of S. acutus; S. candezei is designated as a synonym of S. affinis Guerin; S. multifidus is designated a synonym of S. fascicularis; S. bifasciatus is designated a synonym of S. fulvicollis; S. melanocephalus is designated as a synonym of S. antennalis; S. dohrni is designated as a synonym of S. badeni; S. illigerii bifidus Schwarz is designated a synonym of S. illigeri; S. imperialis subtilis and S. i. schenklingi are designated synonyms of S. imperialis; S. horvathi is designated a synonym of S. limatus; S. nigrolineatus is designated a sysnonym of S. nigriceps; S. distinctus is designated a synonym of S. serraticornis; S. superbus championi is designated as a synonym of S. exsolutus; S. punctatus is designated as a synonym of S. germari; S. nigrolineatus is designated a synonym of S. nigriceps; S. hispidus lamotei is designated as a synonym of S. hispidus; S. langei is designated as a synonym of S. schaumi; S. jansoni and S. jansoni bipunctatus are designated as synonyms of S. taeniatus; S. splendidus is designated a subspecies of S. cuspidatus; and S. sanguinolentus is designated as a synonym of S. virgatus. Semiotus superbus kirschi is designated a valid species and S. exsolutus panamensis is recognized as a valid subspecies. The five genera of the subfamily Campsosterninae are also keyed.