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''Oxyops vitiosa'' is a species of weevil in the Curculionidae family. Common names include the melaleuca leaf weevil and the melaleuca snout beetle. It feeds on the leaves and shoots of the broad-leaved paper bark tree, ''Melaleuca quinquenervia'', which is endemic to Australia where it grows on seasonally inundated plains and swampland. It was introduced into Florida in order to help drain flooded portions of the Everglades.〔Ferriter, et al (2004)〕 ==Life cycle== Adult weevils are gray and six to nine millimetres long, the males being slightly smaller than the females. They are usually found on the leaves and twigs of saplings or the new growth of larger melaleuca trees but are inconspicuous and their presence is most noticeable from the holes they chew in the buds, leaves and stems.〔(Featured Creatures )〕 After mating, the females lays eggs singly or in small groups on the tips of young leaves or sometimes on more mature leaves and new plant growth. The eggs are yellow and one millimetre long when laid but the female usually covers them in a protective secretion which dries to form a hard, dark coloured casing. Female weevils can live for up to ten months, during which time they may produce from 500 to 1000 eggs at the rate of up to nine eggs per day.〔Purcell MF, Balciunas JK. 1994. Life history and distribution of the Australian weevil, Oxyops vitiosa (Coleoptera: Curculionidae), a potential biological control agent for Melaleuca quinquenervia (Myrtaceae). Annals of the Entomological Society of America 87: 867-873.〕 The eggs hatch in about a week and the larvae moult four times, eventually reaching about 1.4 millimetres long. They are yellow when newly hatched but later instars are gray and slug-like. As they develop they become covered with a translucent yellowish oily secretion which turns black as faecal material adheres to it. This coating may provide protection from fire ants and other predators.〔(Antipredatory Activity of the Weevil Oxyops vitiosa: A Biological Control Agent of Melaleuca quinquenervia )〕 The larvae often trail a black faecal string behind them. When feeding, they eat through all the layers of the leaf except for the cuticle on the far side, leaving paper-thin trails across the leaf surface as wide as their bodies. They take about seven weeks to develop and migrate downwards as they mature.〔 The fourth instar is the puparium. The larva ceases to feed and crawls or falls to the ground and finds a suitable underground site in which to pupate. It develops a capsule about ten millimetres in diameter which becomes coated with soil that adheres to the oily surface coating. This stage lasts from two to six weeks but usually about four weeks.〔 Various soil types support pupation but success rates may be higher where soils are sandy and well drained. Sites with saturated soils or permanently flooded areas did not support colonisation when the species was introduced in Florida in 1997.〔Center TD. et al. 2000. Field colonization of the melaleuca snout beetle (Oxyops vitiosa) in south Florida. Biological Control 19: 112-123.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Oxyops vitiosa」の詳細全文を読む スポンサード リンク
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