Latest Ordovician-earliest Silurian chitinozoans from the Puna region, north-western Argentina (Western Gondwana)

Biostratigraphy and palaeogeographic implications of Ordovician and Silurian chitinozoa from the High Zagros Mountains, Northern Persian Gulf, Iran

“…The Spinachitina oulebsiri biozone has been recorded from the Hirnantian at numerous localities in the North Gondwana palaeo-province (Le Heron and Craig 2008; Abuhmida 2013; Le Hérissé et al 2013), Turkey (Steemans et al 1996; Paris et al 2007), and Iran (Ghavidel-Syooki 2008; Ghavidel-Syooki et al 2011b; Ghavidel-Syooki 2016, 2017, 2021; Ghavidel-Syooki and Borji 2018; Ghavidel-Syooki and Piri-Kangarshahi 2021). The co-occurrence of chitinozoan species in this biozone is Spinachitina verniersi Vandenbroucke et al, (2009), which has been recorded in the Soom Shale Member of the Cedarberg Formation from South Africa with the latest Hirnantian to probably earliest Rhuddanian age (Vandenbroucke et al 2009); from the Hirnantian, M'Kratta Formation (Well N1-2), northeast of the Algerian Sahara (Paris et al 2000a); Hirnantian, the Lower and Upper members of the Second Bani Formation in the central Anti-Atlas of Morocco (Bourahrouh et al 2004); Hirnantian, the Zapla Formation of northwestern Argentina (De La Puente 2009; De La Puente and Rubinstein 2013); Ordovician-Silurian boundary, northwestern Argentina (De La Puente et al 2020), and Upper Ordovician-Lower Silurian chitinozoans from the Upper Member of the Salar del Rincón Formation, northwestern Argentina (De Le Puente et al 2020).…”

Revision of Ordovician chitinozoan Lagenochitina esthonica sensu lato: morphometrics, biostratigraphy and paleobiogeography

“…However, alongside revised genus- and family-level systematics (Paris et al, 1999), and continuously expanding datasets from different regions in recent years, revisions of several well-known taxa are required. Sporadic discussions on index chitinozoans have been published in recent years, improving the usefulness of these taxa in biostratigraphy (Butcher, 2013; Nowak et al, 2016; Liang et al, 2017, 2019; de la Puente et al, 2020), but more work is required to further improve the chitinozoan biozonal schemes in general.…”