Fossil Genera in Elateridae (Insecta, Coleoptera): A Triassic Origin and Jurassic Diversification

Abstract

Insect fossils bear important information about the evolutionary history of the group. The fossil record of Elateridae, a large cosmopolitan beetle family, has been greatly understudied and the available data are often replete with ambiguity and uncertainty. The research of Elateridae evolution cannot be done without solid genus-group name concepts. In this study we provide an updated comprehensive summary of the fossil genera in Elateridae, including their systematic placement and information on the type species, gender, number of species, age range, and relevant bibliography. We list seven valid fossil genera in Agrypninae, one in Cardiophorinae, two in Dendrometrinae, five in Elaterinae, two in Negastriinae, one in Omalisinae, one in Pityobiinae, and 36 in Protagrypninae. Additional 19 genera are tentatively classified as Elateridae incertae sedis, and their placements are discussed. Further, we move genera Babuskaya Martins-Neto & Gallego, 2009, Cardiosyne Martins-Neto & Gallego, 2006, Fengningia Hong, 1984 and Gemelina Martins-Neto & Gallego, 2006 from Elateridae to Coleoptera incertae sedis. We also discuss the genera previously placed in Elateridae, which are currently not included in the family. The data on the fossil generic diversity suggest that Elateridae originated in the Triassic and rapidly diversified and became comparatively abundant through the Jurassic. We call for further research on the fossil Elateridae from various deposits in order to increase our knowledge on the origin, evolution, and palaeodiversity of the group.

X-ray micro-computed tomography reveals a unique morphology in a new click-beetle (Coleoptera, Elateridae) from the Eocene Baltic amber

“…Regarding the Elateridae, exceptionally preserved fossils from Eocene ambers provide significant information about the evolution and diversification of this beetle family 2,6,28,53 . During the mid-Paleogene, all major presentday subfamilies already existed and had diversified 51 , which is documented by the fossil record of Agrypninae, Elaterinae, Dendrometrinae, Cardiophorinae, Negastriinae, Pityobiinae, and Omalisinae (Table 1), and further supported by recent dated molecular phylogenies, which date back the origin of the main Elateridae lineages to the Mesozoic [66][67][68] . However, although Elateridae are quite common in various Mesozoic and Cenozoic amber deposits 1,2,28,69 , their true diversity remains underexplored.…”

“…This is mainly a result of their extremely homogeneous external appearance which is constrained by the development of the pro-mesothoracic clicking mechanism 41 . The problems surrounding a uniform morphology and multiple independent origins of various characters historically used for the delimitation of suprageneric taxa have greatly affected the classification of the group, which has been in a constant state of flux for both extinct and extant lineages [41][42][43]51,70 . This also affects the dating of the oldest known fossils for the subfamilies and hence for the whole family, since the placement of some earliest representatives of e.g., Protagrypninae (e.g., Elaterophanes Handlirsch, 1906), Dendrometrinae (Alaodima Dolin, 1980) and Cardiophorinae (Mionelater Becker, 1963) has recently been questioned 51 , and needs critical evaluation (Table 1).…”

“…This included a majority of described species from ambers. For the remaining described fossil species, we used information from extensive literature, including the original descriptions (see Kundrata et al 51 , and references therein). The ZooBank LSID number for this publication is: urn:lsid:zoobank.org:pub:B56223D7-57A5-4543-863D-5CF845DAED3A.…”

“…Elateridae comprise more than 10,000 extant species worldwide 42 , and the fossil record includes approximately 300 species, although the placement of many of them needs thorough investigation 48,49 . They originated and greatly diversified during the Mesozoic 2,50,51 , and are among the most common beetle families recorded in Baltic amber 28,52 . Until now, 16 click-beetle species have been described from Baltic amber, with one classified in Agrypninae, one in Cardiophorinae, two in Dendrometrinae, 10 in Elaterinae, and one incertae sedis 51,53,54 .…”

“…They originated and greatly diversified during the Mesozoic 2,50,51 , and are among the most common beetle families recorded in Baltic amber 28,52 . Until now, 16 click-beetle species have been described from Baltic amber, with one classified in Agrypninae, one in Cardiophorinae, two in Dendrometrinae, 10 in Elaterinae, and one incertae sedis 51,53,54 . Additionally, representatives of more than 20 genera have been reported from Baltic amber without detailed descriptions 28,52,[55][56][57][58][59] , and many yet unstudied specimens are waiting to be examined in various collections.…”