part of overlaps start stage end stage entopterygoid The entopterygoid is a dermal bone that forms the anteroventral and ventral surface of the orbit. It develops as a long sliver of bone developing in the membrane dorsomedial to the palatoquadrate cartilage (3.8 mm NL). endopterygoid mesopterygoid zebrafish_anatomy ZFA:0000657 TAO:0000657 dermatocranium palatoquadrate arch dermal bone quadrate-entopterygoid joint unknown adult