Lower-Middle Triassic Conodont Biostratigraphy of the Mountain Lilu, Timor-Leste

Mountain Lilu in Timor-Leste archives one of the most distinct and continuous Lower to Middle Triassic marine successions along the northeastern margin of Gondwana. We investigated the biostratigraphic framework of this site and established six conodont biozones. They are, namely, the Sweetospathodus kummeli, Neospathodus dieneri, Novispathodus waageni, Chiosella timorensis, Nicoraella kockeli and Paragondolella excelsa zones. These biozones constrain the age of the Mountain Lilu succession from the Griesbachian to the late Anisian. The Induan-Olenekian Boundary is defined by the first appearance of Nv. waageni, while the Olenekian-Anisian Boundary is placed by the first occurrence of Ch. timorensis. The Smithian-Spathian Boundary cannot be precisely defined due to the absence of a key boundary marker. Our results provide a chronobiostratigraphic framework of Timor-Leste, facilitating supra-regional correlation of coeval strata across the Gondwanan and Tethyan domains.