part of part of develops from contributes to morphology of upper lip medial nasal prominence philtrum philtral region of upper lip UBERON:0005402 Philtrum is modelled as the groove rather than the surface structure itself. EHDAA:9280 infranasal depression lip philtrum Wikipedia:Philtrum EMAPA:17926 VHOG:0000862 The vertical groove found on the median line of the upper lip, extending to the nose. FMA:59819 MA:0001577 medial cleft SCTID:362087004 EHDAA2:0001462 surface groove