Permian radiolarian biostratigraphy

Abstract

The Permian Period is one of the most varied times, not only in oceanic environments, but also for the evolution of the radiolarian assemblages. Permian radiolarians have been extensively studied, and great progress has been achieved recently in their biostratigraphy. Seventeen Permian radiolarian zones are summarized here. Among these, seven zones are assigned to the latest Carboniferous–early Permian, namely (in ascending order): the Pseudoalbaillella bulbosa Assemblage Zone, the Pseudoalbaillella u-forma–Pseudoalbaillella elegans Assemblage Zone, the Pseudoalbaillella lomentaria–Pseudoalbaillella sakmarensis Assemblage Zone, the Pseudoalbaillella rhombothoracata Interval Zone, the Albaillella xiaodongensis Assemblage Zone, the Albaillella sinuata Abundance Zone and the Pseudoalbaillella ishigai Abundance Zone. Five zones are attributed to the middle Permian, including the Pseudoalbaillella globosa Interval Zone, the Follicucullus monacanthus Interval Zone, the Follicucullus porrectus Interval Zone, the Follicucullus scholasticus Interval Zone and the Follicucullus charveti Interval Zone. Five zones belong to the middle Permian–late Permian, including the Albaillella cavitata Interval Zone, the Albaillella levis Interval Zone, the Albaillella excelsa Interval Zone, the Albaillella triangularis Interval Zone and the Albaillella yaoi Abundance Zone. These Permian radiolarian biozones and their correlations with conondont zones or other chronostratigraphic schemes are discussed. The phylogenetic model of radiolarians through the Permian Period is also revised.

New Permian radiolarians from east Asia and the quantitative reconstruction of their evolutionary and ecological significances

“…The short range and limited distribution of Longtanella might be related to some climatic changes. Although our data are insufficient to specify this prediction, the early Kungurian is known for the end of late Artinskian–early Kungurian warming and maximum marine flooding event in east Gondwana 89 and the early Capitanian is the time of diversification of Follicucullus species 90 . We hypothesized that Longtanella evolved near east Gondwana to adapt to warmer waters with less input of fresh water around the early Kungurian and lost the competition for survival against the newly diversified Follicucullus species around the early-middle Capitanian.…”

Verifiability of genus-level classification under quantification and parsimony theories: a case study of follicucullid radiolarians

“…A time tree was constructed with the paleotree package (Bapst 2012) in R, with stratigraphic ranges of species from their first and last appearance data. We considered only those 38 species with known stratigraphic ranges (Xiao et al 2018; Zhang et al 2018), and Holdsworthella annulata and Holdsworthella nodosa were chosen as outgroup taxa because of their greater stratigraphic age. Then, an ancestral state reconstruction (ASR) of phylogenetically informative characters was conducted at the genus level in R with the ape package (Paradis and Schliep 2019) to track models of trait change.…”

Integrated Radiolarian and Conodont Biostratigraphy of the Middle to Late Permian Linghao Formation in Northwestern Guangxi, South China

“…Six radiolarian zones are reported from this section. Since the type section, definition and modification histories of these zones are discussed in detail by Zhang et al (2018), we follow their work here and only repeat essential information for this section. The detailed descriptions of each zone are provided below:…”

“…Coming into the 21 st century, these assemblage zones have gradually been replaced by the more detailed interval or lineage zones (Ishiga, 1990;Zhang et al, 2014). Besides southern China and southwestern Japan, Permian radiolarian zones have also been widely recognized, in Italy, Japan, Russia, USA, and South East Asia Reed, 1992, 1995;Kuwahara, 1997;Sashida et al, 2000;Xia et al, 2004;Wang et al, 2006Wang et al, , 2012Jin et al, 2007;Feng, 2008, Feng et al, 2009;Wu et al, 2010;Zhang et al, 2014Zhang et al, , 2018Xiao et al, 2018;Nestell et al, 2019). In recent years, the number of Permian radiolarian zones has gradually increased from the original 9 to 17 zones (Zhang et al, 2018).…”

“…In general, Permian radiolarian biostratigraphy is more complete and detailed than that of any other epoch of the Paleozoic era (see Aitchison et al, 2017). However, a series of problems have arisen, which can be summarized as follows: 1) the accuracy of the radiolarian zones, such as Neoalbaillella and Albaillella interval zones, is not always consistent and different authors apply differing definitions to these zones (Yao et al, 2001), resulting in many obstacles to correlate between these zones in their studies (e.g., Zhang et al, 2018, but also see Xiao et al, 2018); 2) the resolution of Permian radiolarian zones is still low compared to conodont zones, and precise age constraints for most radiolarian zones remain undetermined (Feng et al, 2009;Zhang et al, 2018). A high-resolution correlative framework is still needed for sections that contain both radiolarian and conodonts, or other standard fossil groups.…”