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Grey planthopper - Anzora unicolor

By N A Martin (2017)

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Click to collapse Classification Info





Anzora unicolor (Walker, 1862)

Click to collapse Common names Info

Grey planthopper

Click to collapse Synonyms Info

Massila unicolor Walker, 1862

Melicharia unicolor (Walker, 1862)

Sephena cinerea Kirkaldy, 1906

Click to collapse Biostatus and distribution Info

This adventive plant hopper from Australia is found in the North Island and the northern half of the South Island of New Zealand. It occurs on its herbaceous and shrub host plants in city gardens and parks as well as native ecosystems.

Conservation status: Widespread, a minor pest on some garden plants.

Click to collapse Life stages and annual cycle Info

Grey planthoppers can be found on plants from Spring to Autumn. Nymphs appear in a mass of white wax in the spring and adults may be found in midsummer. I have not found the eggs or any descriptions of them.

Adults have blue-grey wings that are normally folded to form a steep ‘roof’. The head and body are also grey. There are two pairs of wings, three pairs of legs and one pair of antennae. The compound eyes are on the side of the head. A rostrum that holds the feeding stylets projects from the lower side of the head. The tip of the abdomen of females has an ovipositor for laying eggs.

After mating it is assumed that the female lays a cluster of eggs on a plant. After the nymphs hatch from the eggs, they stay in small groups on plant stems. The young nymphs are white and covered in white fluffy wax and the area where they are living becomes coated with wax. Like the adults the nymphs have a rostrum with the stylets for feeding, three pairs of legs and a pair of antennae. Nymphs go from one stage to the next by moulting. During moulting, the skin on the dorsal side splits and the next stage pulls itself out of the old skin. Older nymphs have wing buds. The white wax extends back to form a tail that is usually held close to the plant. At the front, wax on top may extend into horn-like structures.

Walking and flying

The nymphs and adults have three pairs of legs and when disturbed they can jump (hop). The adults have two pairs of wings held over their body.


Like other Hemiptera, the grey planthopper has piercing and sucking mouth parts. The long stylets, special shaped rods, are held in the rostrum. When it wishes to feed, the planthopper moves the tip of the rostrum to a suitable part of the plant. The stylets are then gradually pushed into the plant. The stylets form two tubes, one through which saliva is injected into the plant and a second through which plants juices are sucked up into the insect. The Grey planthopper feeds on the phloem, one of the two systems for distributing nutrients in plants. The planthoppers excrete excess liquid as honeydew.

Click to collapse Recognition Info

The adult Grey planthoppers are easy to distinguish from other insects by their blue-grey colour and the shape of their wings that are held like a ‘steep roof’ and are rounded at their tip. The most similar insect is the Green planthopper, Siphanta acuta (Flatidae). It has a similar shape but is green and the tip of the wings is sharply pointed.

The nymphs of the Grey planthopper may be confused with those of the Green planthopper and the Passion vine hopper Scolypopa australis (Ricaniidae). Nymphs of the Grey planthopper are typically covered in a mass of white wax, some of which forms a fluffy tail and ‘horns’ at the front. The wax on the nymphs of the Green planthopper is mainly restricted to two bundles on the tail that mainly lies flat. The body maybe white, white with reddish markings or green. Nymphs of Passion vine hopper are red-brown with white markings. They also have a fluffy tail that is usually held upright.

Click to collapse Natural enemies Info

The only natural enemy reported is a parasitoid, but grey planthoppers are likely to be preyed upon by other insects, spiders and birds.


A wasp, Dryinus koebelei (Perkins, 1905) (Hymenoptera: Dryinidae) is an ectoparasitoid of the Grey planthopper. The wasp larva lives on the outside of the planthopper nymphs. Its head is under the nymph’s wing buds and it sucks nutrients from the nymph. When the wasp larva is fully grown it leaves the dying planthopper nymph and spins a long thin cocoon in which it pupates. When the adult wasp has emerged from its pupa and its body had hardened, it chews an exit hole in the cocoon.

Click to collapse Host plants Info

Host plants include a fern, herbaceous plants, trees and shrubs. Colonies can be found on young green stems and woody stems. The plants include indigenous species as well naturalised species.

Adults and juveniles feed by inserting their stylets into the phloem of the plant. They excrete excess liquid as honeydew.

In 1925 it was demonstrated that Grey planthoppers were able to spread fire-blight, a disease of some fruit trees.

Table: Host plants of the Grey planthopper, Anzora unicolor (Hemiptera: Flatidae) from Plant-SyNZ database (9 September 2017). The reliability score shows the quality of evidence for the host association (1-10, 10=high).
Common Name(s)Scientific NameFamilyReliability IndexBiostatus
Austral bracken, Bracken, Bracken fern, Common fern, Manehu, rahurahu, Rārahu, Rarauhe, Rarauhe-mahuika, TākakaPteridium esculentum (G.Forst.) CockayneDennstaedtiaceae10indigenous, non-endemic
AsparagusAsparagus officinalis L.Asparagaceae8naturalised
 Chenopodium sp.Amaranthaceae7unknown
Bitou bush, Boneseed, Higgin's curse, Jungle flower, Salt bushChrysanthemoides monilifera (L.) T. Norl. subsp. monilifera (L.) T. Norl.Compositae9naturalised
Large seeded coprosma, Kākaramū, Kākarangū, Karamū, Kāramuramu, KarangūCoprosma macrocarpa CheesemanRubiaceae10endemic
Carrot, Wild carrotDaucus carota L.Umbelliferae10naturalised
WillowherbEpilobium sp.Onagraceae7unknown
tall willowherbEpilobium tetragonum L.Onagraceae10naturalised
Eucalypt, Flowering gum, Gum, StringybarkEucalyptus sp.Myrtaceae7unknown
Fennel, Sweet fennelFoeniculum vulgare Mill.Umbelliferae10naturalised
Shrubby haloragis, ToatoaHaloragis erecta (Banks ex Murray) OkenHaloragaceae10endemic
White tea tree, Kānuka, Kōpuka, Manuea, Mānuka, Mānuka-rauriki, Mārū, Rauiri, RauwiriKunzea ericoides s.l. (A.Rich.) Joy Thomps.Myrtaceae10indigenous, non-endemic
Red tea tree, Tea tree, Kahikātoa, Kātoa, Mānuka, Pata, Rauiri, RauwiriLeptospermum scoparium J.R.Forst. & G.Forst.Myrtaceae10indigenous, non-endemic
Moonah, Tea treeLeptospermum sp.Myrtaceae7unknown
Tall mingimingi, Hukihukiraho, Kaikaiatua, Mānuka-rauriki, Mikimiki, Mingi, Mingimingi, Ngohungohu, TūmingiLeucopogon fasciculatus (G.Forst.) A.Rich.Ericaceae10endemic
Birdsfoot trefoil, LotusLotus pedunculatus Cav.Leguminosae10naturalised
King Island melilot, Small-flowered melilotMelilotus indicus (L.) All.Leguminosae10naturalised
Scrub pohuehue, Small-leaved pohuehue, Wire vine, Pōhue, Pōhuehue, Pōpōhue, Tororaro, WaekāhuMuehlenbeckia complexa (A.Cunn.) Meissn.Polygonaceae10indigenous, non-endemic
NgaioMyoporum laetum G.Forst.Scrophulariaceae10endemic
Marsh ribbonwood, Salt marsh ribbonwood, Houi, Mākaka, RunaPlagianthus divaricatus J.R.Forst. & G.Forst.Malvaceae10endemic
Golden tainui, Gum-digger's soap, Kūmarahou, Kūmararaunui, PāpapaPomaderris kumeraho A.Cunn.Rhamnaceae10endemic
Coastal five finger, Houmāpara, Houpara, Houparapara, Kokotai, Oho, Parapara, WhauwhauPseudopanax lessonii (DC.) K. KochAraliaceae10endemic
Climbing dock, Rambling dock, Turkey rhubarbRumex sagittatus Thunb.Polygonaceae10naturalised
Dock, SorrelRumex sp.Polygonaceae7unknown
FireweedSenecio esleri C.J.WebbCompositae8naturalised
FireweedSenecio hispidulus A.Rich.Compositae10indigenous, non-endemic
Upright hedge parsleyTorilis japonica (Houtt.) DC.Umbelliferae10naturalised
New Zealand oak, Kauere, PūririVitex lucens KirkLabiatae10endemic

Click to collapse Control Info

Grey plant hoppers may be found on some garden plants and crops. If control is thought to be needed, commercial growers should contact their advisors and gardeners should contact a supplier of garden pesticides. If they are a problem in a garden, avoid growing very susceptible plants from where they can spread on to other plants.

In 1925 it was demonstrated that Grey planthoppers were capable of being vectors of fire-blight, a disease of some fruit trees. It is not certain if this is still a problem.

Click to collapse Additional information Info

Research Project

Eggs of the Grey planthopper.

It appears that eggs of the Grey planthopper have not been seen and described. It would be useful to cage some adults in late summer with a selection of favoured plants and try and get them to lay eggs. Then describe the egg masses and record the places they are laid. This could be followed by trying to find eggs in the field and rearing them to see if they are parasitised.

Click to collapse Information sources Info

Lariviere M-C, Fletcher MJ, Larochelle A. 2010. Auchenorrhyncha (Insecta: Hemiptera): catalogue. Fauna of New Zealand. 63: 1-228.

Click to collapse Acknowledgements Info

The New Zealand Plant & Food Research Institute Limited (Plant & Food Research) for permission to use photographs.

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