• McKinley Valentine

Case Moths Build Themselves Blanket Forts and Then Never Leave


Case moths are a native Australian moth that stays in their cocoon way past what any other moth would consider normal. So, #relateable.

They “spin their cases out of silk and most species attach leaves, twigs, sand or soil to the outside for protection and camouflage. There are a number of different species and each species builds a distinctive-looking case, using whatever materials are available to them.”

“Case moths spend most of their lives in the caterpillar phase; this part of their life cycle can last 1-2 years. As caterpillars, they never leave their cases. However, they can be very mobile, dragging their large cocoons along as they move around. They poke the front end of their bodies out the top of their case to feed, collect case decorations, and cling to surfaces as they move about.”

“As they grow, case moths expand their cases from the top (head) end, adding additional twigs as they go. They do this by cutting off appropriately-sized twigs, attaching them temporarily to the top of the case and then disappearing inside to cut a slit where they plan to attach the new stick. This is no mean feat. Case moth cocoons are incredibly tough; cutting a slit for a new stick can take over an hour!”

“If they feel threatened they can seal off the end of the cocoon, cutting a new opening once the threat has passed.”

“The females continue to live in their cases after they’ve pupated into adult moths, but the males leave their cases after pupation to fly off in search of females.”

Let us all forgive ourselves for our case moth ways.

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