First complete specimens of Karslanus (Trilobita, Dameselloidea) from Longha Formation (Cambrian: Guzhangian) , Yunnan, South China

<spacing diaeresis> The trilobite Karslanus Ozdikmen, 2009 (replacement name for Ariaspis Wolfart, 1974, preoccupied) is a presumed dameselloid genus reported from Afghanistan and South China. Until now, it has been known only from fragmentary material. A new species, Karslanus leishuae, from the Fulu Biota in the Longha Formation (Cambrian: Guzhangian) of Yunnan, South China, is represented by complete exoskeletons, the first such material recovered for the genus. Karslanus is unusual among dameselloids in having an holaspid thorax of 10 segments; it is also characterized by a pygidium with the pleurae extended into marginal spines that decrease in length rearward and a natant hypostome. This discovery adds to growing evidence that both conterminant and natant hypostomal conditions are represented among taxa in the superfamily Dameselloidea. (c) 2023 Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. All rights are reserved, including those for text and data mining, AI training, and similar technologies.