''Rhynchodes ursus'', also known as the elephant weevil, is a

weevil Weevils are beetles belonging to the superfamily Curculionoidea, known for their elongated snouts. They are usually small – less than in length – and herbivorous. Approximately 97,000 species of weevils are known. They belong to several fa ...

in the

Curculionidae The Curculionidae are a family of weevils, commonly called snout beetles or true weevils. They are one of the largest animal families with 6,800 genera and 83,000 species described worldwide. They are the sister group to the family Brentidae. Th ...

family. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to New Zealand. It is a wood-boring weevil found throughout New Zealand.

Taxonomy

This species was first described by Adam White in 1846.

Description

The adults of this species were originally described by White as follows: This large weevil has a deep brown colour with two lighter bands near the side of its

thorax The thorax (: thoraces or thoraxes) or chest is a part of the anatomy of mammals and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main di ...

. It has black legs with a spot of yellowish-brown hairs on each

femur The femur (; : femurs or femora ), or thigh bone is the only long bone, bone in the thigh — the region of the lower limb between the hip and the knee. In many quadrupeds, four-legged animals the femur is the upper bone of the hindleg. The Femo ...

. It has dense scales on its body, which can be hair-like. In female specimens the antennae are inserted halfway along the rostrum and nearer the front in males. This species varies greatly in size, colour, and in the amount and nature of its hair-like scales. Male specimens are covered with short scale-like hairs, whilst females have longer, deep brown, or grey, longer more shaggy scale-like hairs. Old individuals are occasionally met with quite black and shining, and almost destitute of any scales whatsoever. The

larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

e of ''R. ursus'' can be distinguished from other weevil larvae as it is large in size and has broad rounded ends to its premedial plates on its exoskeleton.

Distribution

This species is

to New Zealand and is found throughout the country.

Behaviour

This species is active at night and is able to fly.

Hosts

Adult weevils are found on trees, where they gather to feed on sap. Larvae tunnel into dead trunks and branches of southern beeches,

rimu ''Dacrydium cupressinum'', commonly known as rimu, is a species of tree in the family Podocarpaceae. It is a dioecious evergreen conifer, reaching heights of up to , and can have a stout trunk (botany), trunk up to in diameter. It is endemis ...

and ''

Dracophyllum traversii ''Dracophyllum traversii'', commonly known as mountain neinei, grass tree, and pineapple tree is a species of flowering plant in the heath family Ericaceae. It is a deciduous tree (or, in some cases, a shrub) endemic to New Zealand. It reaches ...

''.

Parasites

The larvae of ''R. ursus'' are the host of New Zealand's largest parasitic wasp, ''

Certonotus fractinervis ''Certonotus fractinervis'' is a parasitic wasp found in New Zealand, one of only two species of Labeninae found in New Zealand. It preys on the elephant weevil. Description ''Certonotus fractinervis'' is the largest endemic wasp in New Zeal ...

''. Female wasps use a long

ovipositor The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typica ...

to lay eggs inside the larvae whilst those larvae develop inside trees.

References

External links

* The elephant weevil featured on RNZ ''

Critter of the Week ''Critter of the Week'' is a weekly RNZ National programme about endangered and neglected native plants and animals of New Zealand. Beginning in 2015, ''Critter of the Week'' is an approximately 15-minute discussion between Nicola Toki (origi ...

''
26 August 2022
{{Taxonbar, from=Q53996696 Cryptorhynchinae Endemic beetles of New Zealand Beetles described in 1846 Taxa named by Adam White (zoologist)