Late Ordovician and Early Silurian stromatoporoid sponges from Anticosti Island, eastern CanadaCrossing the O/S mass extinction

2010 ◽  
Author(s):  
Heldur Nestor ◽  
Paul Copper ◽  
Carl Stock
Keyword(s):  
Mass Extinction ◽  
Late Ordovician ◽  
Eastern Canada ◽  
Anticosti Island

Five new genera of Late Ordovician-Early Silurian brachiopods from Anticosti Island, eastern Canada

1995 ◽  
Vol 69 (5) ◽  
pp. 846-862 ◽  
Author(s):  
Paul Copper
Keyword(s):  
New Taxa ◽  
Mass Extinction ◽  
Type Species ◽  
Late Ordovician ◽  
Present Knowledge ◽  
Early Evolution ◽  
New Genera ◽  
Eastern Canada ◽  
Anticosti Island ◽  
First Time

Uninterrupted, ~800 m thick, Ashgill through Llandovery carbonate strata from Anticosti Island (eastern Canada) reveal five new brachiopod genera, enhancing present knowledge about the early evolution of the spire-bearing order Atrypida, spanning some 10.2 million years of time, and a global mass extinction crisis. New taxa include smooth-shelled forms such as the Late Ordovician genus Xysila, type X. astaca n. sp., and two new Early Silurian genera, Becscia, type B. scissura n. sp., and Cerasina, type C. pycnata n. sp. New costate genera include the Early Silurian reef-dwelling form Dihelictera, type D. acrolopha n. sp., and a deeper water inhabitant, Joviatrypa, type J. brabyla n. sp. For comparison with these new taxa, the spiralia and jugal processes of the type species of the Llandovery genera Protatrypa and Meifodia are illustrated and described for the first time.

A Hirnantian (latest Ordovician) reefal bryozoan fauna from Anticosti Island, eastern Canada: taxonomy and chemostratigraphy

2009 ◽  
Vol 46 (3) ◽  
pp. 207-229 ◽  
Author(s):  
Andrej Ernst ◽  
Axel Munnecke
Keyword(s):  
Patch Reef ◽  
Stable Carbon Isotope ◽  
Late Ordovician ◽  
Stable Carbon ◽  
Eastern Canada ◽  
Generic Level ◽  
Rugose Corals ◽  
Stratigraphic Position ◽  
Yield Values ◽  
Anticosti Island

The Natiscotec outcrop on Anticosti Island, Canada (Ellis Bay Formation, Laframboise Member, Hirnantian, Late Ordovician), exposes a patch reef some 20–30 m in diameter, 2–3 m thick, with abundant rugose corals, as well as favositids and heliolitids. Reef capping and flanking sediments include typical Hirnantian brachiopods, such as Hirnantia , Hindella , and Eospirigerina . Within the reef peloidal microbialites encrusting bryozoan colonies are common. The bryozoan fauna includes three cystoporates, seven trepostomes, and three phylloporines. Two genera and two species are new: the cystoporate Natiscotecella tenuis n. gen. and n. sp. and the phylloporine Dilaminocladia natiscotecensis n. gen. and n. sp. Three more species are also new: the cystoporates Ceramopora clara n. sp. and Acanthoceramoporella spinigera n. sp. and the trepostome Revalotrypa honguedensis n. sp. Furthermore, we identify the three trepostomes Atactoporella aff. ortoni (Nicholson, 1874), Hallopora elegantula (Hall, 1852), and Monotrypella cf. aequalis Ulrich, 1882, and a phylloporine Parachasmatopora porkunensis Lavrentjeva, 1985. Four species are identified at generic level and in open nomenclature: the three trepostomes Lioclemella sp., Calloporella sp., and Trepostomata sp. and a phylloporine ? Ralfinella sp. The bryozoan fauna shows some affinities with the Late Ordovician fauna of Scandinavia. Stable carbon isotope investigations from brachiopod shells of the same outcrop yield values for δ13C of up to +6.7‰, which represent the highest values reported from the Anticosti succession so far. This indicates that the stratigraphic position of the outcrop is at or close to the peak of the globally recognized Hirnantian δ13C excursion.

scholarly journals Early athyride brachiopod evolution through the Ordovician-Silurian mass extinction and recovery, Anticosti Island, eastern Canada

2017 ◽  
Vol 91 (6) ◽  
pp. 1123-1147 ◽  
Author(s):  
Paul Copper ◽  
Jisuo Jin
Keyword(s):  
Mass Extinction ◽  
Early Group ◽  
Eastern Canada ◽  
Internal Structures ◽  
Stratigraphic Ranges ◽  
Anticosti Island ◽  
Extinction Events ◽  
Mass Extinction Events ◽  
Shed Light

AbstractThe subfamily Hindellinae is an early group of athyride brachiopods, characterized by a simple jugum that connects the laterally directed spiralia, which are disjunct from the crura. Four genera (Hindella, Cryptothyrella, Koigia, and Hyattidina) are reexamined on the basis of their internal structures, such as the crura and their connection to the hinge, the jugum, and spiralia. The internal brachidium and shell of the Aeronian genus Cryptothyrella differ substantially from those of Hindella. Elkanathyris pallula n. gen. n. sp. is recognized as a posteriorly ribbed hindellide of Aeronian age. These genera are transferred from the Meristellinae to the subfamily Hindellinae (family Hindellidae). On Anticosti Island, Hindella is confined to the Hirnantian (latest Ordovician): it became extinct at the end Ordovician during the last of several mass extinction events that also extinguished the Laframboise reefs at the top of the Ellis Bay Formation. Post-extinction recovery of athyrides was pioneered by small-shelled Koigia, which are abundant in the basal Silurian Becscie Formation. Hyattidina, with a simple brachidium, is abundant in the Aeronian and Telychian of Anticosti, but absent earlier. True meristellines, as envisioned here, first appeared in the Aeronian Gun River Formation. The revised taxonomy and stratigraphic ranges of these earliest athyrides shed light on the nature of the Ordovician–Silurian mass extinction and recovery, and help refine the biostratigraphy of the O-S boundary interval.

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