0000000000928871
AUTHOR
Ivars Zupiņš
Galvenā devona lauka osteolepiformu kārtas daivspurzivis (Sarcopterygii, Osteolepiformes)
GALVENĀ DEVONA LAUKA OSTEOLEPIFORMU KĀRTAS DAIVSPURZIVIS (SARCOPTERYGII, OSTEOLEPIFORMES) Ivars ZupiĦš ANOTĀCIJA Revidēts osteolepiformu kārtas daivspurzivju taksonomiskias sastāvs un stratigrāfiskā izplatība Galvenā devona lauka (Austrumeiropas platformas ziemeĜrietumu daĜas) teritorijā. Kritiski izvērtēts morfoloăisko pazīmju kopums un sniegtas sugu precizētas diagnozes. Konstatēts, ka darbā apskatāmajā teritorijā kārta pārstāvēta ar 16 sugām, kas pieder 9 ăintīm. Aprakstīta jauna tristihopterīdu suga Eusthenopteron kurshi sp. nov., izvērtējot osteolepiformu iespējamo pielietojamību devona nogulumu biostratigrāfijā, konstatēts, ka grupai ir zināma nozīme kā vienam no mugurkaulnieku faunas…
Taphonomy of the vertebrate bone beds from the Klūnas fossil site, Upper Devonian Tērvete Formation of Latvia
Combined sedimentological and taphonomical study of the siliciclastic sequence of the Tērvete Formation in the stratotypical area was aimed at revealing the formation of the three oryctocoenoses discovered and related structural and textural features of the deposits, as well as at detailed observation of the taphonomical peculiarities of the obtained palaeontological material. The fossil vertebrate assemblage is represented by 14 taxa comprising placoderms, acanthodians, sarcopterygians and actinopterygians. The three oryctocoenoses, first recognized in 2010, differ in the proportions of repeatedly buried material, in the number and degree of preservation of small and fragile skeletal eleme…
Ventastega curonica and the origin of tetrapod morphology.
The gap in our understanding of the evolutionary transition from fish to tetrapod is beginning to close thanks to the discovery of new intermediate forms such as Tiktaalik roseae. Here we narrow it further by presenting the skull, exceptionally preserved braincase, shoulder girdle and partial pelvis of Ventastega curonica from the Late Devonian of Latvia, a transitional intermediate form between the 'elpistostegids' Panderichthys and Tiktaalik and the Devonian tetrapods (limbed vertebrates) Acanthostega and Ichthyostega. Ventastega is the most primitive Devonian tetrapod represented by extensive remains, and casts light on a part of the phylogeny otherwise only represented by fragmentary ta…