has quality has quality in taxon develops from develops from capable of capable of mucus secretion Branchiostoma grooved surface structure Hatschek's pit UBERON:0009865 A deep ciliated fossa on the dorsal midline of the buccal cavity (the region of the gut behind the mouth). Among other things, it secrets mucus which entraps food particles from the water[WP]. Wikipedia:Hatschek's_pit Hatschek's left diverticulum ciliated pit