''Monteithiella humeralis'', commonly known as the pittosporum shield bug is a species of herbivorous

shield bug Pentatomidae is a family of insects belonging to the order Hemiptera, generally called shield bugs or stink bugs. Pentatomidae is the largest family in the superfamily Pentatomoidea, and contains around 900 genera and over 4700 species.Robert ...

native to

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

and introduced in

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

. It is the only species of the genus ''Monteithiella'', making ''Monteithiella'' a

monotypic taxon In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of Genus, genera, the term ...

. As its common name suggests, it is most commonly observed feeding on ''

Pittosporum ''Pittosporum'' ( or The first pronunciation is that expected for traditional English pronunciation of Latin, Anglo-Latin; the second is common in nurseries. ''Sunset Western Garden Book,'' 1995:606–607) is a genus of about 250 species of flow ...

'' plants.

Description

''Monteithiella humeralis'' adults are 9mm long with predominantly brown bodies and pale green legs. First instar

nymphs A nymph (; ; sometimes spelled nymphe) is a minor female nature deity in ancient Greek folklore. Distinct from other Greek goddesses, nymphs are generally regarded as personifications of nature; they are typically tied to a specific place, land ...

are small and black, with circular bodies and white spots on the upper surface of the abdomen. Later nymph stages are similar to the first but with orange spots instead of white.

Life history

Adult females lay blue eggs on the underside of leaves which turn white after 2–3 days, and hatch after 5 days. Nymphs progress through 5 instars or juvenile stages before reaching adulthood. It takes around 41 days after eggs are laid for bugs to mature to adulthood. In New Zealand, adults are most abundant in November and March. while eggs and nymphs can be found from November to April.

Ecology

In both New Zealand and Australia, pittosporum shield bugs are most commonly found feeding on species of ''

'', and to a lesser extent ''

Coprosma ''Coprosma'' is a genus of flowering plants in the family Rubiaceae. It is found in New Zealand, Hawaiian Islands, Borneo, Java, New Guinea, islands of the Pacific Ocean to Australia and the Juan Fernández Islands. Description The name ''Copros ...

''. In New Zealand, pittosporum shield bugs are widespread but are not considered a pest. They are known to be attacked by ''

Trissolcus basalis ''Trissolcus basalis'', or the green vegetable bug egg parasitoid, is a parasitoid wasp in the family Platygastridae known primarily for parasitising the horticultural pest ''Nezara viridula'', the green vegetable bug. Description Like other ...

'', a

parasitoid wasp Parasitoid wasps are a large group of hymenopteran Superfamily (zoology), superfamilies, with all but the wood wasps (Orussoidea) being in the wasp-waisted Apocrita. As parasitoids, they lay their eggs on or in the bodies of other arthropods, ...

of pentatomid egg masses introduced into New Zealand in 1949 to control ''

Nezara viridula ''Nezara viridula'', commonly known as the southern green stink bug (USA), southern green shield bug (UK) or green vegetable bug (Australia and New Zealand), is a plant-feeding stink bug. Believed to have originated in Ethiopia, it can now be f ...

''.

Gallery

File:Monteithiella humeralis 59268904.jpg, Front view File:Monteithiella humeralis 50546968.jpg, Underside File:Monteithiella Nymph.jpg, Late-instar nymph

References

{{Taxonbar, from=Q10588782 Hemiptera of Australia Pentatomidae