Oak silk moth

The oak silk moth (ヤママユガ, Yamamayuga) is a relatively rare insect found on trees during summer nights. It is notable for being very skittish, and will fly away much more willingly than other tree insects. When flying away, it makes a distinct loud flapping sound.

In City Folk
Upon donating to the Museum, Blathers the curator will say;

"While the oak silk moth has impressively large wings, it's said that this moth isn't a very skilled flier. ...I should think that might be the reason it developed such big, vulgar eyeballs..."

The oak silk moth can be found on the second level of the Insect exhibit, in the middle segment with the easternmost stump.

In New Leaf
Upon being donated, the creature can be found in the room of the bug exhibit with the Rafflesia in, resting on a tree on the east side of the room. It can be seen better if the camera is adjusted. The exhibit has this to say about the Oak Silk Moth:

"Oak silk moths are seen in the summer and are one of the largest moth species in the world. They make silk from their mouths as they transition into the pupa stage. As adults, they don't eat anything and only live off the nutrients they stored while they were caterpillars."

Encyclopedia Information
When the player has caught an oak silk moth, they can find information about the insect in the bug menu. Below is the information regarding the oak silk moth:

New Leaf

 * Size-328 mm (large)
 * Season- Summer
 * Time- Night

Further Information
The hercules Moth, named the Oak Silk Moth, not to confuse with the hercules Beetle, are among the largest moths in the world. Both their body and wings have the record, but their bodies are quite small compared to their wings. They are named after the hero of Greek Mythology. Like in game, when scared, they flee, releasing a very heavy flap. Transparent sections on the wings in some moths and butterflies help serve as a camouflage, so that predators, don't see the insect, but rather whatever is behind it. Atlas moths are a saturniid moth, a group that includes the famous luna moth. Despite what their common name suggests, they are only distant cousins of the domestic silk moth (Bombyx mori) which belong to the family Bombycidae.