|Dorsal view of Monteithiella humeralis on Pittosporum leaf|
Monteithiella humeralis, commonly known as the pittosporum shield bug is a species of herbivorous shield bug native to Australia and introduced in New Zealand. As its common name suggests, it is most commonly observed feeding on Pittosporum plants.
Monteithiella humeralis adults are 9mm long with predominantly brown bodies and pale green legs. First instar nymphs 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.
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.
In both New Zealand and Australia, pittosporum shield bugs are most commonly found feeding on species of Pittosporum, and to a lesser extent Coprosma. In New Zealand, pittosporum shield bugs are widespread but are not considered a pest. They are known to be attacked by Trissolcus basalis, a parasitoid of pentatomid egg masses introduced into New Zealand in 1949 to control Nezara viridula.
- Marie-Claude., Larivière (2004). Heteroptera (Insecta: Hemiptera) : catalogue. Larochelle, André, 1940 April 10-, Manaaki Whenua-Landcare Research New Zealand Ltd. Lincoln, N.Z.: Manaaki Whenua Press, Landcare Research. ISBN 978-0478093582. OCLC 56351081.
- Marie-Claude., Lariviere (1995). Cydnidae, Acanthosomatidae, and Pentatomidae (Insecta: Heteroptera) : systematics, geographical distribution, and bioecology. Manaaki Whenua-Landcare Research New Zealand Ltd. Lincoln [N.Z.]: Manaaki Whenua Press. ISBN 978-0478093018. OCLC 34575913.
- Martin, N. A. (2016). "Pittosporum shield bug - Monteithiella humeralis. New Zealand Arthropod Factsheet Series Number 29". Interesting Insects and other Invertebrates.
- McDonald, F. J. D.; Grigg, Janice (1980). "The life cycle of 'Cuspicona simplex' Walker and 'Monteithiella humeralis' (Walker) (Hemiptera: Pentatomidae)". General and Applied Entomology: The Journal of the Entomological Society of New South Wales. 12: 61–71.
- Prendergrast, J. G. (1963). "Observations on the biology and immature stages of Antestia orbona Kirkaldy (Hemiptera, Pentatomidae)". New Zealand Entomologist. 3:2 (2): 19–25. doi:10.1080/00779962.1963.9723055.
- Cumber, R. A. "The egg-parasite complex (Scelionidae: Hymenoptera) of shield bugs (Pentatomidae, Acanthosomidae: Heteroptera) in New Zealand". New Zealand Journal of Science. 7:4: 536–554.