If the the sun were on the left in an eclipse it would make a CONCAVE shape but this drawing shows what appears to be a larger circle on the left with a CONVEX shape. The only answer I could come up with is are we to believe the body on the left, even though drawn as a larger circle, is supposed to be the moon? Would this represent their importance placed on the moon? Otherwise, this glyph makes no sense. 
Reference my remark, “I regard 99 percent of archaeoastronomy claims as absurd”. :’)