Warm-water Dasycladaceae algae from the Late Ordovician of the Parahio Valley, Spiti, India

Warm-water Dasycladaceae algae Mastopora and Cyclocrinites were for the first time recorded from the Takche Formation (Upper Ordovician-lower Silurian), Parahio Valley, Spiti, India. They are preserved as external and internal moulds of the non-globular or possibly bulb-like cortical skeleton showing flattened thalli with a high degree of compaction. The occurrence of abundant cyclocrinitid remains in the Takche Formation indicates that the Spiti region of the northwestern Himalaya must have been located at about 30° palaeolatitude during the Late Ordovician and early Silurian. The cyclocrinitids were warm-water algae and their extinction at the end of the Ordovician is related to cooling and glaciations. The cyclocrinitids in the Ordovician are known from several localities in central and southern Asia, including Kazakhstan and western China.