Any shapes with icosahedral or octahedral symmetry will also contain tetrahedral symmetry. Assembly of the icosahedral capsid occurs on modified membranes from the endoplasmic reticulum. HSV is a double-stranded DNA virus that has icosahedral capsid. The RNA is surrounded by a three-layered icosahedral protein capsid. The capsid is an arrangement of 60 protomers in a tightly packed icosahedral structure. Picornaviruses are non-enveloped, with an icosahedral capsid. The envelope covers the T = 4 icosahedral capsid. For both octahedral and icosahedral symmetry there are six forms. Viruses in this family have small protein virions that exhibit T=1 icosahedral symmetry. All of these consist of regular tetrahedral and icosahedral cells. Viruses in Flavivirus are enveloped, with icosahedral and spherical geometries. It is nonconvex with 60 golden rhombic faces with icosahedral symmetry. These can also be seen in these 4 convex polyhedra with icosahedral symmetry. The viral particle is about 30 nm in diameter with icosahedral symmetry. Other morphologies have also been described&colon; spindle shaped, rod shaped, filamentous, icosahedral and spherical.