Netizens curious as unusual “yellow-black insect” enters home

Anoplophora horsfieldii

19th June 2024 – (Hong Kong) As the Hong Kong weather turns hot, residents in various districts have begun to notice the presence of peculiar insects. Recently, a netizen discovered a yellow-black insect with a broken right antenna in his home. Seeking assistance in identifying the creature, the netizen shared a photo on Facebook. Some netizens recognised the insect as a member of the longhorn beetle family (Anoplophora horsfieldii), one of Taiwan’s “Three Treasures” of longhorn beetles.

Anoplophora horsfieldii can grow up to approximately 35 mm in length. These beetles have a black or dark brown body with large irregular pale yellow bands on their wing covers (elytra). They also possess pale yellow markings on their head, pronotum, and remarkably long antennae. The primary host plants for these beetles include Camellia sinensis, Celtis sinensis, Quercus glauca, and Ulmus pumila. While it is more commonly found in Taiwan, it has also been spotted in the New Territories area of Hong Kong in recent years.

The netizen who discovered the insect uploaded the photos to a local Facebook group and asked fellow netizens, “What kind of insect is this that just flew into my home?” Based on the photos, the insect’s appearance featured yellow-black colouration with long antennae. However, its right antenna seemed to be partially broken. In two additional pictures, the creature was seen placed inside a transparent container. The homeowner mentioned that they found the insect with its right antenna already damaged, stating, “When it flew in, I noticed that the right antenna was already broken.”