Biting Midges (Diptera: Ceratopogonidae) from Cambay Amber Indicate that the Eocene Fauna of the Indian Subcontinent Was Not Isolated

Abstract

India’s unique and highly diverse biota combined with its unique geodynamical history has generated significant interest in the patterns and processes that have shaped the current distribution of India’s flora and fauna and their biogeographical relationships. Fifty four million year old Cambay amber from northwestern India provides the opportunity to address questions relating to endemism and biogeographic history by studying fossil insects. Within the present study seven extant and three fossil genera of biting midges are recorded from Cambay amber and five new species are described: Eohelea indica Stebner & Szadziewski n. sp., Gedanohelea gerdesorum Stebner & Szadziewski n. sp., Meunierohelea cambayana Stebner & Szadziewski n. sp., Meunierohelea borkenti Stebner & Szadziewski n. sp., and Meunierohelea orientalis Stebner & Szadziewski n. sp. Fossils of species in the genera Leptoconops Skuse, 1889, Forcipomyia Meigen, 1818, Brachypogon Kieffer, 1899, Stilobezzia Kieffer, 1911, Serromyia Meigen, 1818, and Mantohelea Szadziewski, 1988 are recorded without formal description. Furthermore, one fossil belonging to the genus Camptopterohelea Wirth & Hubert, 1960 is included in the present study. Our study reveals faunal links among Ceratopogonidae from Cambay amber and contemporaneous amber from Fushun, China, Eocene Baltic amber from Europe, as well as the modern Australasian and the Oriental regions. These findings imply that faunal exchange between Europe, Asia and India took place before the formation of Cambay amber in the early Eocene.

Peer Review #1 of "Lygistorrhinidae (Diptera: Bibionomorpha: Sciaroidea) in early Eocene Cambay amber (v0.1)"

“…However, given the overall similarity of the three species in proportions of body regions, appendages, and wing venation, these differences do not warrant erecting a separate genus. The finding adds another record to the pattern of apparently shared fossil taxa between Cambay and Baltic amber, as already been reported from the Diptera (Grimaldi & Singh, 2012;Stebner et al, 2017), bees (Engel et al, 2013), and termites (Engel et al, 2011). The most unexpected finding is Lygistorrhina in Cambay amber.…”

Baltic amber impact on historical biogeography and palaeoclimate research: oriental rove beetleDysanabatiumfound in the Eocene of Europe (Coleoptera, Staphylinidae, Paederinae)

“…Stebner et al . ). The latest radiometric attempt by Ritzkowski () who dated the glauconitic marine sediments of the Prussian Formation on Sambian Peninsula using the K–Ar method, inferred its middle Eocene age, with the lower layer of the Blue Earth being 44.1 ± 1 Ma and the underlying Wild Earth 47.0 ± 1.5 Ma.…”

“…and Rovno amber, while the comparison with Fushun amber implied the early Eocene age for Baltic amber (Stebner et al . ). Considering that the amber forests in the Baltic region could have persisted for several million years up to the end of the Eocene (e.g.…”

“…Weitschat & Wichard ), this finding does not contradict the faunal similarities between Baltic amber and the middle Eocene Eckfeld Maar (Stebner et al . ). However, Vitali & Daamgard () suggested an Early Oligocene age for Baltic amber, due to the temperate nature of Opsimini (Coleoptera), that are found there.…”

“…Szwedo & Sontag , ; Alekseev & Alekseev ; Stebner et al . ) and the high palaeontological and palaeoenvironmental significance of their resolution, we undertake a succinct review of this complex matter in this paper. Also, we provide a summary of problems associated with the use of systematically poorly known Paederinae in general in palaeobiology.…”