T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Beetle (Giraffe) Lasiorhynchus barbicornis

Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Superfamily: Curculionoidea
Family: Brentidae
Subfamily: Brentinae
Genus: Lasiorhynchus
Species: L. barbicornis
Binomial name: Lasiorhynchus barbicornis
Common name: New Zealand giraffe beetle, tuwhaipapa, New Zealand’s giraffe weevil, 

Lasiorynchus barbicornis is a straight-snouted flying beetle of the family Brentidae (it is not a weevil). It is endemic to New Zealand and the male is New Zealand longest native beetle at 85mm, the females are half the size at 45mm.
This species displays extreme sexual dimorphism which is mostly due to the elongation of the male rostrum. Focal observations have determined the role of the males very large rostrum is as a weapon during male-male contests.
The male has antennae at the end of the rostrum, whilst females have a reduced protrusion with antennae about halfway along. Having the antennae in this position allows the female leaves it mouth free to bore into bark of dying trees to lay their eggs. The egg laying takes place during October to March. The hatch grub then tunnels for two years into the tree or log. The adult leaves a distinctive square hole when it leaves the tree. The adults live for only two weeks. 

A female beetle. It has a shorter rostrum and her antennae are not at the end of its rostrum like the males.
 



A large male giraffe weevil guards a drilling female. 






The New Zealand endemic giraffe beetle (Lasiorhynchus barbicornis) have been found with assemblage of mites on their bodies. There appears to be at least 4 different mite morpho-types observed on an average beetle. It is not known if these mites are parasitising the beetles in order to survive and reproduce, or using the weevils as a vehicle of dispersion (phoresy).
Photo of a male New Zealand giraffe beetle (Lasiorhyncus barbiconus) with mites attached to the thorax.