Mites (Acari)
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red palm mite, Raoiella indica, magnified about 300x; Photo by Eric Erbe, digital colorization by Chris Pooley, USDA-Agricultural Research Service |
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red palm mite, Raoiella indica; Photo by E. Erbe, E. Kane, and R. Ochoa, USDA-ARS |
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red palm mite, Raoiella indica, adult females; Photo by Rita Duncan, University of Florida |
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red palm mite, Raoiella indica, egg, larva, and adult male (left to right); Photo by Rita Duncan, University of Florida |
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red palm mite, Raoiella indica, damage; Photo by Jorge Pena, University of Florida |
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red palm mite, Raoiella indica, damage, close-up; Photo by Jorge Pena, University of Florida |
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nut damage and sap bleeding to Samoan coconut (a variety of Cocos nucifera) caused by an unidentified eriophyid mite; Photo by Scot Nelson, University of Hawaii at Manoa |
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distorted and damaged coconuts (Cocos nucifera) caused by unidentified eriophyid mites; Photo by Scot Nelson, University of Hawaii at Manoa |
Rank & taxon
Order Acari
Description
Adult: Mites may range in size from tens of microns up to about 1 millimeter in length. They vary widely in appearance, but in general, share a few characteristics. Unlike other arachnids, mites have no apparent external segmentation, appearing instead as a single body mass. They have two body regions, the gnathosome (mouthparts) and idiosome (everything else). Like other arachnids, they generally have 4 pairs of legs, but some species have fewer, with either two or three pairs of legs. Mites do not have antennae.
Larvae: While generally of a smaller size and having 3 pairs of legs instead of 4, larvae often look similar to the adult stage.
Distribution
Worldwide; over 50,000 described species, but over 1 million species are thought to be living
Biology/life cycle
Mites generally have four stages in their life cycle: egg, larvae, nymph, and adult. The time required to complete the life cycle varies widely, often depending on environmental conditions such as temperature and humidity. Mites live in virtually every habitat on earth, including soils, caves, crops and food stocks, even hydrothermal vents and Antarctic cliffs, and may be aquatic or terrestrial. Mites may be phytophagousphytophagous:
feeding upon plant matter
, parasiticparasitic:
living in close association with another species (host), feeding upon it while providing no benefit
, predatory, or detritivorous.
Hosts
Palms: a wide variety of palms
Other: a wide variety of plants
Representative taxa on palms
The red palm mite, Raoiella indica (Family Tenuipalpidae), is a pest of several ornamental and agricultural species of palms. It is native to Asia and the Middle East, but has invaded the Caribbean and the United States. Their reddish color makes them easy to spot against green leaves. They are generally found on the lower surfaces of leaves and usually cause yellowing of the leaves which can be severe in large infestations. In the Western Hemisphere, the red palm mite is known to feed on at least 32 palm species, as well as banana, heliconias, gingers, and some other monocots.
The coconut mite, Aceria guerreronis (syn. Eriophyes guerreronis; Family Eriophyidae) is one of the most notorious pests of coconut palms (Cocos nucifera). It attacks the developing fruits, causing distortion of the fruit. This mite is invisible to the unaided eye, and is found in the Americas and West Africa.
Additional comments
There are only a few mite species that can be detected with the unaided eye or with a handlens. The majority of mite species are microscopic and are detected due to the damage they cause to the plant rather than direct observation of the pest.
