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Fossil materials are shown to be important for testing phylogenetic and biogeographic hypotheses based on extant insects. Fossil records indicate that paraphyletic groups are common in classification of insects. Extant genera of biting midges (Ceratopogonidae) noted in the fossil record are reviewed and their age and distribution analyzed. The oldest extant genera are at least 125 million years old. The share of extant genera in the fossil record gradually grows from 20% in the Lower Cretaceous to 100% in the Oligocene -Miocene. Most of the extant genera have or had a wide (mostly global) distribution. Limited distributions on the Southern Hemisphere concern the relict genera Austroconops, Metahelea, Meunierohelea and Physohelea, which have fossil records on the Northern Hemisphere. A wide distribution, present or past, of most genera of the biting midges analyzed, indicates that complete land bridges or continental drifts did not have a significant influence on their migrations onto new territories. The distribution of biting midges supports views that ecological conditions determined mostly by climate and competition are the most important factors influencing insect distribution. Biogeographic scenarios based exclusively on recent distributions of extant fauna should be treated with great caution.
The Late Cretaceous belemnite family Belemnitellidae Pavlow, 1914, which includes nine genera and two subgenera, occurs only in the Northern Hemisphere, that is in the North European and North American palaeobiogeographical Provinces of the North Temperate Realm, in addition to the northern margin of the Tethyan Realm in Europe. The North European Province is subdivided into the Central European, Central Russian and Baltoscandian Subprovinces. The centre of origin and dispersal of the belemnitellids lay in the North European Province and all known genera and subgenera occur there. The belemnitellids immigrated intermittently into the Tethyan Realm (at least nine times) and the North American Province (at least six times). The majority of the species occurring in the Tethyan Realm are conspecific with those from the North European Province, whereas the species occurring in the North American Province are endemic, with a few exceptions. The endemic species probably evolved by allopatric speciation from initial migrants. More than a score migrations have been recognized within the subprovinces of the North European Province. The palaeogeographical distribution and migration patterns of the belemnitellids were to a certain extent controlled by eustatic sea-level changes, cool or warm climatic phases and competition, although the cause of several migration events cannot be satisfactorily explained at present.
Chitinozoans from seven cores in the Middle Ordovician upper Goldwyer and Nita formations are documented, and three assemblages are delineated. Six out of twelve species found in the Canning Basin, in eastern Gondwana, are also found in Laurentia, confirming the close relationship between chitinozoans in the two palaeocontinents. The assemblages correlate with Zone 05 of Combaz & Peniguel, and the undefined zone immediately overlying the Cyathochitina jenkinsi Zone in the biozonation designed for Laurentia. The relationship between contemporaneous assemblages in Baltica, Avalonia and the northern Gondwana Domain is discussed with a small number of species in common with Baltica and Avalonia, and no definite links with northern Gondwana. Two new species Calpichitina windjana, and Belonechitina vibrissa are described.
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