Life History of E. imperialis
E. imperialis is one of the largest North American silk moths, with females having a wingspan of up to nearly 7". The larvae of E. imperialis be any color from red to green to brown. Early larval stages (known as instars) have large scoli protruding from their thorax and the tip of the abdomen. These scoli may be used as a defense mechanism, as larvae will wave them threateningly when stressed. The scoli will gradually get smaller each time the caterpillar molts. Later instars have fine hairs coming off the body and after the third instar the caterpillar will have eye spots down the side of its body. After 5 instars, the caterpillar will pupate, forming a brown chrysalis. After overwintering as a pupa, the adults emerge in late spring or early summer. Adults are yellow with brown markings and eye spots on each wing, but the overall coloration is incredibly variable. Adults have no digestive system, and only live for a very short amount of time. They emerge, mate, and die within a span of two days. |
Image 1: copyright Whatsthatbug.com, Image 2 and 3: copyright Donald W. Hall, Image 4: copyright Jacob Manley
|
|
Eacles imperialis specimens at Cornell
There are tons of specimens of Eacles imperialis in the Cornell University Insect Collection (CUIC). In fact, there are roughly 150 preserved adults! While many of them were collected in the past twenty or thirty years, some date back as far as 1924. |