labial sensillum morphology variant dauer sensillum variant dauer labial sensillum variant WBPhenotype:0001557 C_elegans_phenotype_ontology Dauer stage animals exhibit variations in the quantity, structure or organization of the sensilla of the mouth compared to control. In C. elegans, these sensillum are arranged in two (inner and outer) concentric rings around the mouth. dauer labial sensillum abnormal