Morphological variability and phylogeny of the upper Tithonian–Berriasian Vallupinae (Radiolaria) from the Mariana Trench

Abstract

As one of the highly diversified radiolarian groups in the Mesozoic, Vallupinae occurred widely in the tuffaceous claystone from the Mariana Trench of the upper Tithonian–Berriasian where the specimens are extremely well-preserved. The occurrence of diversified Vallupinae presented here is further evidence that the range of Vallupinae extends to Berriasian. The stratigraphic range and proposed possible phylogenetic relationships within the Subfamily Vallupinae are provided and 17 radiolarian species of this subfamily are presented, including three new species: Vallupus gracilis, Mesovallupus brevispina, and Neovallupus mediforma.