abnormal digestive system development abnormal buccopharyngeal membrane morphology csmith 2014-01-01T17:21:59Z MPheno.ontology MP:0012521 abnormal pharyngeal membrane morphology any structural anomaly of the thin bilaminar membrane derived from the prechordal plate that is devoid of mesoderm and formed by the apposition of the stomodeal ectoderm with the foregut endoderm; after the embryonic head fold has evolved it lies at the caudal limit of the stomodeum, forming a septum between the primitive mouth and pharynx; the membrane eventually disappears, and thus a communication is established between the mouth and the future pharynx abnormal oral plate morphology abnormal oral membrane morphology abnormal pharyngeal septum morphology abnormal oropharyngeal membrane morphology