Chieseiceras dolomiticum n. sp. (Ammonoidea) and its significance for the calibration of the Triassic platform interior stratigraphy at Latemar (Southern Alps, Italy)

Abstract

The species Chieseiceras dolomiticum n. sp. along with other ammonoid species (Latemarites latemarensis, Halilucites rusticus) helps constraining the age of the cyclic platform interior portion at Latemar (Dolomites, northern Italy). The comparison of ammonoids from the Latemar platform with the fossil record in basinal successions in the Southern Alps (including the Ladinian GSSP section at Bagolino) and Hungary suggests that the entire rhythmically bedded Latemar interval is entirely late Anisian in age. More than 400 stratigraphical metres of bedded shallow water carbonates at Latemar are found to correspond to less than 5 m of siliceous nodular limestone in the pelagic succession at Bagolino. The refined correlation will be significant for the reassessment of the cyclic Latemar stratigraphy in the light of new geochronological calibration of the South Alpine Middle Triassic.