Tree Frog and Thin-winged Longicorn Beetle: Behind the Scenes | Wild Korea 2

In this video, I found and observed a single tree frog. At first, I identified it as a Japanese tree frog, but after taking a closer look, I noticed that it was smaller than expected and unusually pale green, which made it seem slightly different. However, its body markings and lateral pattern were closer to the features commonly seen in Japanese tree frogs. The calls recorded in the previous video, "Wild Korea | Nature & Wildlife 1," were also those of Japanese tree frogs and boreal digging frogs.

I remained cautious because the individual's body and head appeared slightly smaller and more slender than those of a typical Japanese tree frog. In particular, Suweon tree frogs have been reported near the filming location, so I could not rule out that possibility. Japanese tree frogs can also vary in size and coloration depending on growth stage, sex, condition, and environment. Pale green and relatively small individuals are not unusual, so those features alone are not enough to identify a Suweon tree frog. The two species are very similar in appearance, and even experts may find it difficult to distinguish them accurately from photographs or video alone. Males can be distinguished by their calls, but genetic analysis is required to determine whether hybridization has occurred. In this case, neither the species nor possible hybridization could be confirmed from appearance alone. However, because I could not completely rule out the possibility that it was a Suweon tree frog, which is designated as Endangered Wildlife Class I in South Korea, I limited the encounter to observation and returned the frog to the exact place where it was found. Suweon tree frogs are generally smaller than Japanese tree frogs and are known for their low, metallic calls. The male vocal sac may appear yellow to golden. Before collecting a wild tree frog, the species should be identified carefully. If a frog is unusually small, or its vocal sac color and call differ from those normally heard, making it difficult to distinguish from a Suweon tree frog, it is safer to leave it in place and document it with photographs and audio. If it has already been moved, it should be returned promptly to the original location. The Suweon tree frog is a protected species designated as Endangered Wildlife Class I in South Korea.

The praying mantis was also returned to the place where it was found after filming. Because I had previously reared a thin-winged longicorn beetle through adult emergence, I collected Mesosa myops, Pterolophia caudata caudata, and a thin-winged longicorn beetle during the previous field survey. I observed mating, but the Mesosa myops and Pterolophia caudata caudata individuals were in poor condition, so during this filming I returned them to a dead old tree near where they had originally been found. The thin-winged longicorn beetle is known as a forest pest that damages trees, so I decided to keep it in captivity rather than release it outdoors.