Poroporo gall mite - Tetra martini
By N A Martin (2018)
Classification
Arthropoda
Arachnida
Acari
Trombidiformes
Prostigmata
Eriophyoidea
Eriophyidae
Phyllocoptinae
Anthocoptini
Tetra martini Manson, 1984
Common names
Poroporo gall mite, Poroporo russet mite
Biostatus and distribution
This endemic gall mite was first found in 1980 on leaves of one of its two host plants, Poroporo, Solanum aviculare (Solanaceae). The infected plants were near New Plymouth and were being grown for pharmaceutical steroids. Feeding on young leaves causes russeting and distortion. It has also been found in Auckland and on Solanum laciniatum. It is present in gardens and native habitats.
Conservation status: Probably widespread, where its host plants are present.
Life stages and annual cycle
Life stages of Haloragis gall mite, Aceria victoriae (Acari: Eriophyidae). Creator: Nicholas A. Martin. © Diagram modified from drawings published in Transactions of the Royal Society of New Zealand. 85 (3), page 462, Text-Fig. 2. [Image: 2GSN]
This gall mite is very tiny. Adult mites are about 0.182-0.202 mm long. The adult mite is like a tiny white cow's horn with two pairs of legs at the wide end of the horn. Adult female mites lay tiny spherical eggs. The larva that hatches from an egg looks like a tiny adult. The mite larva moults (changes skin) into a nymph. There is one nymphal stage that also looks like a small adult. The last juvenile stage moults into an adult mite. There are males and females.
Walking
The mite uses their legs for walking, but it can also hold on to the plant with the tip of its abdomen, which acts as a sucker.
Feeding and leaf damage
The mites have pointed mouth parts that puncture the surface cells of young leaves from which they suck up the cell sap. During feeding, the mites may inject saliva into the plant. Mite feeding is associated with distortion of young leaves and may be associated with both physical damage to young cells and from injection of mite saliva.
Dispersal to new shoots and new plants
When the plant grows new leaves, adult female mites disperse to these and their feeding causes leaf damage. It is presumed mites walk from the older leaves to the new growths.
When this gall mite colonises new plants, it is unlikely that mites walk all the way. It is believed that most mites are dispersed by wind. Some species of mite climb to prominent places on plants and stand waiting for a gust of wind to take them away.
Drawing of side view of Poroporo gall mite, Tetra martini (Acari: Eriophyidae). The adult mite is very tiny, 0.182-0.202 mm long. Creator: Dave Manson. © drawing published in Fauna of New Zealand 1984, vol. 4, fig. 401. [Image: 2WX7]
Poroporo gall mites, Tetra martini (Acari: Eriophyidae) on a leaf of Poroporo, Solanum aviculare (Solanaceae): note the tiny spherical eggs. Creator: DSIR Photographers. © Landcare Research. [Image: 2WX5]
Poroporo gall mites, Tetra martini (Acari: Eriophyidae) on a leaf of Poroporo, Solanum aviculare (Solanaceae): note the tiny spherical eggs. Creator: DSIR Photographers. © Landcare Research. [Image: 2WX6]
Leafy shoot of Poroporo, Solanum laciniatum (Solanaceae), damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2WWX]
A leaf of Poroporo, Solanum laciniatum (Solanaceae), damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae) and an undamaged leaf Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2WWW]
Leafy shoot of Poroporo, Solanum aviculare (Solanaceae), damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae). Creator: DSIR Photographers. © Plant & Food Research. [Image: 2WX0]
Shoot of Poroporo, Solanum aviculare (Solanaceae), with no gall mite feeding damage to its leaves. Creator: DSIR Photographers. © Plant & Food Research. [Image: 2WX2]
Shoot of Poroporo, Solanum aviculare (Solanaceae), with leaves damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae). Creator: DSIR Photographers. © Plant & Food Research. [Image: 2WX3]
Recognition
This mite requires special procedures and taxonomic knowledge to identify specimens. However, its presence on a plant can be recognised by plant damage symptoms. This mite species is the only one known to cause leaf russeting and distortion of young leaves of Poroporo, Solanum aviculare and Solanum laciniatum (Solanaceae).
Leafy shoot of Poroporo, Solanum aviculare (Solanaceae), damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae). Creator: DSIR Photographers. © Plant & Food Research. [Image: 2WX1]
A flowering shoot of Poroporo, Solanum aviculare (Solanaceae), with leaves damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae). Creator: DSIR Photographers. © Plant & Food Research. [Image: 2WX4]
Leafy shoot of Poroporo, Solanum laciniatum (Solanaceae), damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2WWV]
Leafy shoot of Poroporo, Solanum laciniatum (Solanaceae), damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2WWX]
Natural enemies
No natural enemies of the Poroporo gall mite have been observed. A possible predatory mite (Acari, Phytoseiidae) has been seen in a colony of the gall mites.
An adult mite (Acari: Phytoseiidae) on a Leafy shoot of Poroporo, Solanum aviculare (Solanaceae), with a colony of Poroporo gall mite, Tetra martini (Acari: Eriophyidae). The Phytoseiid mite is a potential predator of the gall mite. Creator: DSIR Photographers. © Plant & Food Research. [Image: 2WWY]
Two mites and an egg (Acari: Phytoseiidae) on a Leafy shoot of Poroporo, Solanum aviculare (Solanaceae), with a colony of Poroporo gall mite, Tetra martini (Acari: Eriophyidae). The Phytoseiid mites are potential predators of the gall mite. Creator: DSIR Photographers. © Plant & Food Research. [Image: 2WWZ]
Host plants
Poroporo gall mite is known from Poroporo, Solanum aviculare and Solanum laciniatum (Solanaceae). It feeds on the young leaves.
Feeding and plant damage
The mites have pointed mouth parts that puncture the surface cells of young leaves from which they suck up the cell sap. During feeding, the mites may inject saliva into the plant. Mite feeding is associated with distortion of young leaves and may be associated with both physical damage to young cells and from injection of mite saliva.
Leafy shoot of Poroporo, Solanum aviculare (Solanaceae), damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae). Creator: DSIR Photographers. © Plant & Food Research. [Image: 2WX1]
Shoot of Poroporo, Solanum aviculare (Solanaceae), with no gall mite feeding damage to its leaves. Creator: DSIR Photographers. © Plant & Food Research. [Image: 2WX2]
Leafy shoot of Poroporo, Solanum laciniatum (Solanaceae), damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae). Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2WWV]
A leaf of Poroporo, Solanum laciniatum (Solanaceae), damaged from feeding by Poroporo gall mite, Tetra martini (Acari: Eriophyidae) and an undamaged leaf Creator: Nicholas A. Martin. © Plant & Food Research. [Image: 2WWW]
Common Name(s) | Scientific Name | Family | Reliability Index | Biostatus |
---|---|---|---|---|
Bullibul, Bullibulli, Kangaroo apple, Pōpopo, Poroporo, Poroporotanguru | Solanum aviculare G.Forst. | Solanaceae | 10 | indigenous, non-endemic |
Bullibul, Bullibulli, Large kangaroo apple, Pōpopo, Poroporo, Poroporotanguru | Solanum laciniatum Aiton | Solanaceae | 9 | indigenous, non-endemic |
Additional information
Eriophyid gall mites belong to the super family Eryiophyoidea. These mites have several unusual features. For example, though most mites have four pairs of legs like spiders, Eriophyoid mites have only two pairs of legs. Many of these mites can induce host plants to form galls, some of which may be very complex. Some species of these mites can transmit plant viruses that may cause plant diseases and plant death.
Information sources
Manson DCM. 1984. Eriophyoidea except Eriophyinae (Arachnida: Acari). Fauna of New Zealand. 4: 1-142.
Acknowledgements
The New Zealand Plant & Food Research Institute Limited (Plant & Food Research) for permission to use photographs.
Landcare Research New Zealand Limited (Landcare Research) for permission to use photographs.