GEOMETRIC MORPHOMETRIC APPROACH TO ESTABLISH PHYLOGENETIC AFFINITIES OF ENIGMATIC PTEROSAUR SPECIMENS FROM THE LOWER CRETACEOUS OF SOUTH KOREA

Abstract

Fragmentary but scientifically important pterosaur fossils have been reported in Lower Cretaceous strata such as the Jinju and Hasandong formations of South Korea. Recently, several large teeth and a second wing phalanx found in these strata have been suggested to have affinities with Boreopteridae, a clade in which has so far been reported only in the Yixian Formation of China. Here, the phylogenetic affinities of these proposed boreopterid specimens are reassessed, using two-dimensional geometric morphometric shape analyses. The morphometric analyses found the South Korean pterosaur teeth in different morphospaces from the Yixian Fm. boreopterids, and plot them closer to anhanguerians. An isolated second wing phalanx does plot close to a boreopterid Zhenyuanopterus longirostris in a morphospace defined by first two principal component axes, but taxa from different lineages are also plotted as closely, or even closer. Thus, there seems to be no clear evidence that these specimens belong to Boreopteridae, and the tooth fossils appear to be very different from those of established members of this clade. Therefore, the hypothesis that some South Korean pterosaur fossils can be referred to boreopterids, is here tentatively rejected.