An Early Ordovician (late Tremadocian) bivalve fauna from Iran

Abstract

A small bivalve fauna is described from the late Tremadocian of Iran, adding to the very few localities in the world where bivalves of this age are known. In addition to indeterminate praenuculids, the fauna includes the praenuculid Pensarnia and the pteriomorphian genus Glyptarca. The former is otherwise known from South Wales and the latter, from South and Mid‐Wales and West Yunnan, China.

Ordovician of North Iran: New lithostratigraphy, palaeogeography and biogeographical links with South China and the Mediterranean peri-Gondwana margin

“…18 -rhyolite agglomerate tuffs; 19 -rhyolite tuffs, 20 -basalt volcanic rocks. Global geochronological scale and conodont biozonation are mainly after Cooper et al (2012) with emendations, chitinozoan biozonation for Mediterranean peri-Gondwana is after Paris (1990).…”

“…Their Late Ordovician age was 1 -diamictites/olistostrome horizons; 2 -conglomerate and siltstone intercalations; 3 -sandstones; 4 -sandstones and siltstones; 5 -sandstone, siltstone and argillite intercalations; 6 -siltstones and argillites; 7 -green and light grey argillites; 8 -black shales; 9 -limestone and argillite intercalations; 10 -oolitic ironstones; 11 -calcareous argillites and siltstones; 12 -argillaceous limestones; 13 -limestones; 14 -tuffs; 15 -basalt volcanic rocks. International Chronostratigraphical Scale and conodont biozonation are mainly after Cooper et al (2012) with emendations.…”

The first Early Ordovician graptolites and marine incursions in eastern Alborz, Iran

“…semnanensis Popov et al 2009, bivalve Glyptarca sp. (Cope & Ghobadi Pour, 2020) and numerous unidentified ostracods.…”