A new bothriolepid antiarch, Vietnamaspis trii gen. et sp. nov., is described from the Middle-Upper Devonian sandstones of the Dô Son peninsula, near Haiphong, Vietnam. The site is north of the Song Ma suture zone on the South China Terrane, and contains a fauna including Bothriolepis and groenlandaspids. Vietnamaspis gen. nov. is characterized by having a long, parallel-sided posterior median dorsal plate, and an anterior median dorsal plate with a narrow anterior margin. Vietnamaspis gen. nov. is regarded as a sister taxon to Bothriolepis and Grossilepis because it has a relatively large axillary foramen on the anterior ventrolateral plate. The Australian bothriolepid Bothriolepis warreni Long 1983 is referred to a new genus, Briagalepis gen. nov., because it has very short overlap surfaces for the anterior dorsolateral plate on the anterior median dorsal plate, and lacks a reticulate dermal ornament.
- New genus