An Early Triassic conodont with periodic growth?
- 1China University of Geosciences, 29 Xueyuan Road, Beijing 100083, China
- 2Department of Geology, University of Leicester, Leicester LE1 7RH, UK
Abstract. Elements of a new Triassic conodont genus Parapachycladina, from the Lower Triassic Beisi Formation of western Guangxi Province, China, show a characteristic pattern of lamellar edges in the recessive basal margin. The lamellae are grouped in sets of 8–10, with broad interlamellar spaces between each set. If this apparent periodicity reflects annual cycles, the specimens were not more than four years old when they ceased growing.