''Aceria guerreronis'', the coconut mite, is an

eriophyid Eriophyidae is a family of more than 200 genera of mites, which live as plant parasites, commonly causing galls or other damage to the plant tissues and hence known as gall mites. About 3,600 species have been described, but this is probably ...

mite Mites are small arachnids (eight-legged arthropods). Mites span two large orders of arachnids, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari, but genetic analysis does not show clear e ...

which infests coconut plantations. It is economically devastating, and can destroy up to 60% of coconut production. The immature nuts are infested and injured by mites feeding in the portion covered by the perianth of the immature nut.

Description

The coconut mite is small, with a length of about and a width of ; this is too small to see with the naked eye. The mite is white and translucent, long and slender, with two pairs of legs. Populations build up rapidly, and the presence of this mite is generally indicated by the damage it does, and confirmed microscopically.

Distribution

''Aceria guerreronis'' was first described by Hartford H Keifer in 1965 from Mexico, but it is unclear whether it originated from the Old or New World. The coconut palm originated in the South Pacific region and spread along the coasts of Asia, and later Africa. It was introduced into the Americas by traders in the sixteenth century, but whether the mite moved with it or arrived in some other way is not known. The

coconut palm The coconut tree (''Cocos nucifera'') is a member of the palm tree family (Arecaceae) and the only living species of the genus ''Cocos''. The term "coconut" (or the archaic "cocoanut") can refer to the whole coconut palm, the seed, or t ...

(''Cocos nucifera'') is the only known

host A host is a person responsible for guests at an event or for providing hospitality during it. Host may also refer to: Places * Host, Pennsylvania, a village in Berks County People *Jim Host (born 1937), American businessman * Michel Host ...

, apart from a single record in South America of it occurring on '' Lytocaryum weddellianum'', a related species of palm. More recently, it has also been reported on ''

Borassus flabellifer ''Borassus flabellifer'', commonly known as doub palm, palmyra palm, tala or tal palm, toddy palm, wine palm or ice apple, is native to South Asia (especially in Bangladesh & South India) and Southeast Asia. It is reportedly naturalized in Socot ...

'' and '' Syagrus romanzoffiana''.

Life cycle

The adult female mite lays eggs on the developing coconut fruit about a month after pollination. The site chosen is under the remnants of the

perianth The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower, and structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla ( petals) or tepals when ...

which is no longer pressed so tightly against the fruit at this stage in the fruit's development and that enables the mite to access the area. After the eggs have hatched, the developing larvae thrust their mouthparts into the plant's soft tissues and suck out the juices. The whole developmental cycle takes ten days so numbers of mites can increase rapidly. The mites are probably largely dispersed by wind, but

phoresy Phoresis or phoresy is a non-permanent, commensalistic interaction in which one organism (a phoront or phoretic) attaches itself to another (the host) solely for the purpose of travel. Phoresis has been observed directly in ticks and mites s ...

may also occur, with the mites inadvertently being carried by pollinating insects, rodents or birds, to other palm trees.

Damage

Coconuts injured by Eriophyes guerreronis

''Aceria guerreronis'' is the only member of its family considered to be a serious pest of coconuts. Coconuts take about twelve months to mature. Damage from the initial infestation under the perianth becomes apparent as the fruit develops and more of its surface becomes visible. The nut develops corky brown, fissured patches of damaged tissue and becomes distorted if the damage is on one side of the fruit and not the other. Further attacks on the same nut can occur but the number of mites present decreases as the nut nears full size, and by the time the nut is harvested, it is usually devoid of mites. Estimates of the amount of economic damage done by the mite range up to 60%.

References

{{Taxonbar, from=Q4673206 Eriophyidae Agricultural pest mites Animals described in 1965 Arachnids of North America Coconuts Taxa named by Hartford H Keifer