March flies and European Cenozoic palaeoclimates (Diptera: Bibionidae)

Abstract

The proportions of the different bibionid genera are used to estimate the temperature changes between the Late Eocene and the Late Miocene in Western Europe. The genus Plecia is a good indicator of the warm Cenozoic palaeoclimates. We propose a new approach for the estimation of the value of the palaeoclimatic information that could be obtained by actualistic inferences using extinct taxa. Other taxa (i.e. Mastotermitidae) that could appear a priori better palaeoclimatic indicators result to be less sensitive than bibionids to temperature changes. Intraspecifi c and intrageneric morphological diversity is explored for the genera Bibio, Penthetria and Plecia, showing the diffi culties to characterize the fossil bibionid species. Résumé. Les Bibionidae et le climat cénozoïque européen (Diptera).Les proportions des différents genres de Bibionidae sont utilisées afi n d'estimer les changements de temperatures entre l'Eocène terminal et le Miocène terminal en Europe de l'Ouest. Le genre Plecia s'avère un bon indicateur des paléoclimats chauds au Cénozoïque. Nous proposons une nouvelle approche d'estimation de la valeur des informations paléoclimatiques qui peuvent être obtenues par des inférences actualistes basées sur des taxons éteints. Des taxons (Mastotermitidae) qui peuvent apparaître a priori comme des indicateurs paléoclimatiques plus évidents que les Bibionidae sont en fait moins sensibles que ces derniers aux changements de température. La diversité morphologique intraspécifi que et intragénérique est explorée pour les genres Bibio, Penthetria et Plecia, montrant les diffi cultés de caractérisation des espèces fossiles dans cette famille.

The first fossil insect from the deep-water marine Early Miocene of Zillerleite, Germany

“…Fossil bibionid flies of the genus Penthetria have been more frequently found in Oligocene deposits than in Neogene deposits, possibly due to the continuous cooling of the climate in Europe during the Miocene (Collomb et al, 2008). Skartveit and Nel (2016) recorded seven species of Penthetria from French Oligocene deposits, and additional species of the genus that need revision, were described from the Oligocene of Germany (Statz, 1943;Wedmann, 1998).…”

First record of the march fly genus Plecia (Diptera: Bibionidae) in Dominican amber

“…Flies of the family Bibionidae are among the most abundant insects in Tertiary fossil assemblages (Wedmann 1998; Collomb et al 2008) and numerous species have been named from Palaearctic and Nearctic deposits. In contrast, bibionids are relatively uncommon in amber (brasero et al 2009;skartveit 2009;ZHerikHin et al 2009) and rather few species have been described from this medium (meunier 1907;Hardy 1971;Waller et al 2000;Gee et al 2001;skartveit 2009).…”

“…The genus Plecia Wiedemann, 1828 is a speciose, tropical and subtropical (skartveit 1997;Collomb et al 2008) group of flies with a particularly rich fossil record. In the current fauna, the genus is confined to areas with warm climates; its distribution extends north to the southeastern USA (denmark et al 2010) and to the Primorye region of Russia (krivosHeina & krivosHeina 1998).…”

Gaps and nodes between fossil and extant insects

“…The impact of climatic macro‐fluctuations on insect faunas can be investigated based on this record (Dumont et al, 2005). Climatic macro‐fluctuations themselves can even be inferred from the insect fossil record (Collomb et al 2008, and references therein). Ultimately, considering the dynamics of taxonomic diversity together with insect palaeoecological preferences, and palaeoenvironmental data, should allow identification of the major extrinsic factors responsible for the diversity of insects (Labandeira, 2005).…”