Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Hexapoda
Class: Insecta
Superorder: Coleopterida
Order: Coleoptera
Suborder: Polyphaga
Infraorder: Scarabaeiformia
Superfamily: Scarabaeoidea
Family Scarabaeidae
Subfamily: Melolonthinae
Tribe: Stethaspini
Genus: Stethaspis
Scientific name: Stethaspis longicornis
Common name: Mumu chafer

Stethaspis longicornis is a native beetle found in the northern half of New Zealand. It can be distinguished from Stethaspis suturalis (Tanguru chafer) by the lack of a yellow stripe on its back and its more northern distribution. It flies with a buzzing sound early evening in summer. The beetle’s grubs feed on tree roots.

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Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/