 However, a more complete phylogenetic analysis showed that "Sinopterus" may actually be an intermediate step in the grade between "H. jii" and the other two "Huaxiapterus" species, making "Sinopterus" paraphyletic if "H. jii" is included.In 2016, another species, "S. lingyuanensis", was named.It differs from other species in the proportions of its nasoantorbital fenestra, its rostral index, the relative sizes of its femur and tibia, and the relative sizes of the first and second wing digits.