Post-Kellwasser event recovery and diversification of phacopid trilobites in the early Famennian (Late Devonian)

Phacopid trilobites in post-Taghanic Givetian through Frasnian cephalopod limestones, Montagne Noire (France) and related areas (Thuringia, Morocco)

“…pronini Maximova, 1955 respectively. The biostratigraphical position of the latter species, occurring in the "Crickites Zone" according to Maximova (1955, p. 193), raises the question of whether an earliest Famennian ("post Iδ") age could be considered (Feist 2019). However, the species is said to be associated with the last scutelluids that became extinct at the terminal Frasnian Kellwasser crisis.…”

“…The terminal Frasnian Kellwasser Event severely affected the Phacopidae as no lower rank taxon survived into the Famennian (McNamara & Feist 2016). In sharp contrast the early Famennian recovery is characterised by high innovation rates when five new genera with some 38 species successively appear (Feist 2019).…”

“…ocular devices are still perceptible in the form of minute protuberances crossed by the facial suture in the anteriormost adaxial corner of the cheek. Such configuration is reminiscent of some species of early Famennian Pulvinocephalus, Trifoliops and Trimerocephalus though direct phyletic links between these taxa to latest Frasnian ones have not been established with certainty (Feist 2019).…”

The Hushoot Shiveetiin gol section (Baruunhuurai Terrane, Mongolia): sedimentology and facies from a Late Devonian island arc setting

“…During the Famennian, trilobite diversity was punctuated by several bioevents (Crônier et al 2013). In the late part of the Early Famennian, the significant post-Kellwasser event recovery marked a new step especially for phacopid trilobites with new blind phacopid genera from deep offshore habitats and eyed-phacopid genera from shallower habitats in the photic zone (Crônier et al 2013;Feist 2019).…”

“…Excluding the Americas, Famennian phacopids are characterized by a worldwide distribution (Chlupáč 1975;Crônier and François 2014;Feist 2019). However, if the majority of genera is apparently limited to a single cratonic margin, the other few genera are cosmopolitan (Crônier and François 2014).…”