A new viviparous species of Phrynocephalus from Guinan, Qinghai, China, is described. Phrynocephalus guinanensis sp. nov., differs from all congeners in the following combination of characters: body large and relatively robust; dorsal ground color of head, neck, trunk, limbs and tail brown with weak light brown mottling; lateral ground color of head, neck, trunk and tail light black with weak white-gray mottling in adult males, and green with weak white-gray mottling in adult females; ventral ground color of tail white-gray to black in the distal part of the tail in adult males, and totally white-gray in adult females; ventral surfaces of hind-limbs white-gray; ventral surfaces of fore-limbs brick-red in adult males, and white-gray in adult females; ventral ground color of trunk and head black in the center but, in the periphery, brick-red in adult males and white-gray in adult females. Phrynocephalus guinanensis sp. nov. typically uses desert habitats, whereas P. vlangalii, a species closely related to the new form, uses a variety of arid and semi-arid habitats. It is the nineteenth species of Phrynocephalus recorded from China.

Researchers from Nanjing Normal University,  Hangzhou Normal University and Chengdu Institute of Biology. Researchers from Natural Science Foundation of China and  Nanjing Normal University.