國立自然科學博物館

春夏是蜉蝣的季節。蜉蝣成蟲的口器退化不具取食功能，只有1~3天的壽命，在短暫的時間內完成擇偶、交配和產卵的任務，因其生命短暫而被形容為「朝生暮死」。其實，蜉蝣是很長壽的，生命週期可長達一年以上，期間經歷了卵、稚蟲、亞成蟲及成蟲4個階段。經過20多次脫皮來到亞成蟲，亞成蟲的形體與成蟲無異，再脫皮一次即為成蟲。在昆蟲的世界中，只有蜉蝣目有亞成蟲的階段，非常獨特。圖2、圖3可見亞成蟲時期與脫皮後的成蟲。

Spring and summer are mayfly season. Adult mayflies have vestigial mouthparts therefore do not feed. They live for one to three days, during which they mate and lay eggs. Due to the short lifespan of the adult they are considered as ephemeral. Actually, mayflies are long-lived insects with a life cycle of one year or more under the water. Their development consists four stages: egg, nymph, subimago, and adult. After having more than 20 times molds, they deverlop into the subimago stage, appearing very similar to adults. After a final mold, they become adults. The subimago is a unique stage, only occurs in the order Ephemeroptera. Images 2 and 3 are of mayflies in the subimago and adult stages, respectively.

劉政宜-長壽的蜉蝣1

劉政宜-長壽的蜉蝣2

劉政宜-長壽的蜉蝣3