ABSTRACT: Moscovian conodont assemblages of South China are dominated by P1 elements of the untroughed genus Idiognathodus and the troughed genus Swadelina. The Eurasian species Sw. cf. Sw. concinna (Kossenko), Sw. subexcelsa (Alekseev and Goreva), and Sw. makhlinae (Alekseev andGoreva), aswell as the North American species Sw. nodocarinata (Jones), have been recovered fromMoscovian strata at theNaqing and Fengtin sections in Luodian (southern Guizhou, SouthChina). Two new species, the early Moscovian Sw. lancea n. sp. and the lateMoscovian Sw. lanei n. sp. are described. Two Swadelina species, Sw. dissecta (Kossenko) and Sw. neoshoensis (Lambert, Barrick and Heckel), were not recorded in South China. The stratigraphically oldest species of Swadelina, Sw. einori (Nemirovskaya and Alekseev) and Sw. subdelicata (Wang and Qi), appeared in the middle Bashkirian. Swadelina einori is interpreted to have given rise to Sw. lancea n. sp. and perhaps Sw. subexcelsa and Sw. concinna in the early Moscovian. The older forms, Sw. einori, Sw. subdelicata, and Sw. lancea n. sp., disappeared in the early Moscovian. Swadelina subexcelsa probably evolved into Sw. makhlinae and Sw. lanei n. sp. in the late Moscovian. Swadelina nodocarinata may be related to Sw. einori or the similar Sw. cf. Sw. nodocarinata. The younger species, Sw. cf. Sw. concinna, Sw. subexcelsa, Sw. makhlinae, Sw. nodocarinata, and Sw. lanei n. sp., became extinct in the late Moscovian.

Files