part_of part of part of adjacent to adjacent to adjacent_to multi-tissue structure embryo cloacal membrane embryonic cloacal fold uberon EHDAA2:0004009 One of the pair of mesenchymal swellings (folds) located on either side of the cloacal membrane during the indifferent stage of embryonic development; cranial to the cloacal membrane the folds unite to form the genital tubercle; caudally the folds are subdivided into urogenital folds anteriorly and anal folds posteriorly. cloacal fold UBERON:0012292 We presume this is distinct from AAO:0001003, an external integumentary structure - check with amphibian anatomy ontology developers. AO notes: the text def states mesenchymal swelling, EHDAA2 splits into mesenchymal and epithelial parts One of the pair of mesenchymal swellings (folds) located on either side of the cloacal membrane during the indifferent stage of embryonic development; cranial to the cloacal membrane the folds unite to form the genital tubercle; caudally the folds are subdivided into urogenital folds anteriorly and anal folds posteriorly external anal region