The locations of all 24 bugs are as follows.

Ant: Kakariko Village. The male ant is located on a tree to the right of the hole in the back of the Kakariko graveyard and the female ant is in the house just prior to the bomb shop on the west side of the village.

Beetle: Faron Province, Hyrule Field. The male beetle is located on a tree in the southern portion of Hyrule Field. The tree is positioned between two raised land masses. As for the female, she is on a tree on the western side of the field. It is just south of the giant dirt patch.

Butterfly: Hyrule Field east of Castle Town. Just south of the east entrance of Castle Town is a small flower patch containing the male. To find the female, she is on a vine-covered ledge just northeast of the east castle town exit.

Dayfly: Gerudo Desert. To find the male you must search the southern part of the desert, almost dead center, north of the barricades. For the female, search the trenches at the southeast end of the desert (near the chunk of bridge). It is recommended that you do this at nightfall.

Dragonfly: Zora's Domain. The male is on top of the hill at the southwest end of the domain. The female is right in front of the boating game shack.

Grasshopper: Eldin Province, Hyrule Field. The male is at the entrance to Kakariko Village. The female is at the northeastern part of the map. This is best done at night.

Ladybug: South of Castle Town. The male is on the vine covered pillar southwest of the gate. The female is near the three trees of the left side of the balcony.

Mantis: Great Hylian Bridge. The male is on the wall of the northern half of the bridge. The female is on a rock just south of the bridge. It is easier to find her by looking at the bridge.

Phasmid: Eldin Bridge. The male is on the arch on the south end of the bridge. The female is on a cliff to the north of the bridge. You will need the Clawshot.

Pill Bug: Kakariko Gorge. The male is on the southern end of the bridge. The female is found by some flowers on the southwest corner, north of the bridge.

Snail: Sacred Grove. The male is on the inside of the southwestern alcove. The female is inside the Temple Of Time, on west side of the staircase.

Stag Beetle: Hyrule Field north of Castle Town. The male is near a tree on the east side of the bridge. The female is on the northern side of the field, above a bombable entrance to an icy cave.