This histological study of the proventriculus of the Yemen honey bees, Apis mellifera jementica illustrates the
complexity of this structure. It was differences found between queens and workers, as well as between different stages
within the same caste. The proventriculus has growth degrees in the different growth stages during metamorphosis. For
queens, the first to third day of pupal stage, were studied, whereas virgin worker pupae were observed at days one, four
and seven. In addition, queens and workers were examined throughout the adult stage. The results indicated that the
proventriculus tissue in the pupal stage is characterized by reformation of the foregut (crop and proventriculus), with the
proventriculus gaining spines, teeth and a noticeably thicker chitin layer. The adult stage is characterized by caste-specific
tissue changes based on food type. Furthermore, in adults, the proventriculus terminates with four moving, triangularshaped
flanges fitted with a number of spines and teeth and covered by a thick layer of chitin.