genus enterovirus Type species Human enterovirus C Virion properties morphology CPs 1B, 1C and 1D of the human enteroviruses and rhinoviruses are among the largest in the family (VP13 chain lengths, 238–302 aa), and this is reflected in the typically long interβstrand loops, the larger than average thickness of the capsid wall (46 Å), and a surface relief that is strongly pronounced compared to most other picornaviruses.