Have you seen these bugs Crossing?

Common Butterfly
Price: 90 Bells
Location: Near Flowers
Available: March-Sept
Morn-Noon
Peak Catching: Apr-June Noon

Yellow Butterfly
Price: 90 Bells
Location: Near Flowers
Available: March-Sept
Morn-Noon
Peak Catching: Apr-June Noon

Tiger Butterfly
Price: 160 Bells
Location: Near Red and Pink Flowers
Available: March-Sept
Morn-Noon
Peak Catching: May-June Noon

Peacock
Price: 220 Bells
Location: Near Blue, Violet and Black Flowers
Available: March-Sept
Morn-Noon
Peak Catching: May-June Noon

Monarch
Price: 140 Bells
Location: Near Flowers
Available: Sept-Nov
Noon

Emperor
Price: 2,500 Bells
Location: Near Flowers (Rare)
Available: June-Sept
Noon

Agrias Butterfly
Price: 3,000 Bells
Location: Near Flowers (Rare)
Available: June-Sept
Noon

Birdwing
Price: 3,000 Bells
Location: Near Flowers (Rare)
Available: June-Sept
Noon

Moth
Price: 60 Bells
Location: Near Outdoor Lights
Available: May-Sept
Night
Peak Catching: June-Aug Night

OakSilkMoth
Price: 1,200 Bells
Location: On Trees (Rare)
Available: June-Sept
Night
list from here here