Scale insects are small insects of the order Hemiptera, suborder Sternorrhyncha. Of dramatically variable appearance and extreme sexual dimorphism, they comprise the infraorder Coccomorpha which is considered a more convenient grouping than the superfamily Coccoidea due to taxonomic uncertainties. Adult females typically have soft bodies and no limbs, and are concealed underneath domed scales, extruding quantities of wax for protection. Some species are hermaphroditic, with a combined ovotestis instead of separate ovaries and testes. Males, in the species where they occur, have legs and sometimes wings, and resemble small flies. Scale insects are herbivores, piercing plant tissues with their mouthparts and remaining in one place, feeding on sap. The excess fluid they imbibe is secreted as honeydew on which sooty mold tends to grow. The insects often have a mutualistic relationship with ants, which feed on the honeydew and protect them from predators. There are about 8,000 described species.
Maconellicoccus hirsutus, is a pest of many plants, trees, and shrubs. It infests hibiscus, citrus, coffee, sugar cane, annonas, plums, guava, mango, okra, sorrel, teak, mora, pigeon pea, peanut, grapevine, maize, asparagus, chrysanthemum, beans, cotton, soybean, cocoa, and many other plants. The pest forms colonies on the host plant, and if left undisturbed, the colonies will grow into large masses of white waxy coverings on branches, fruiting structures, leaves, and even whole plants, including large trees.
Aonidiella aurantii or red scale is an armored scale insect and a major pest of citrus. It is thought to be a native of South China but has been widely dispersed by the agency of man through the movement of infected plant material. In the United States it is known as California red scale. It was first found in California between 1868 and 1875, apparently brought there on planting material imported from Australia.
Coccus viridis is a soft scale insect in the family Coccidae with a wide host range. It is commonly known as green scale or sometimes coffee green scale because it is a major pest of coffee crops throughout the world.
Ortheziidae is a family of scale insects commonly known as the ensign scales or ortheziids. They occur in most parts of the world but the majority of the species are found in the Neotropical and Nearctic regions while there are not many species in Australasia and the Far East. There are twenty valid genera and 198 species.
Paracoccus marginatus, commonly known as the papaya mealybug, is a small sap-sucking insect in the mealybug family, Pseudococcidae. It is found on a number of different hosts, including economically important tropical fruit trees and various ornamental plants.
Planococcus citri, commonly known as the citrus mealybug, is a species of mealybugs native to Asia. It has been introduced to the rest of the world, including Europe, the Americas, and Oceania, as an agricultural pest. It is associated with citrus, but it attacks a wide range of crop plants, ornamental plants, and wild flora.
Coccus hesperidum is a soft scale insect in the family Coccidae with a wide host range. It is commonly known as brown soft scale. It has a cosmopolitan distribution and feeds on many different host plants. It is an agricultural pest, particularly of citrus and commercial greenhouse crops.
Eriosoma lanigerum, the woolly apple aphid, woolly aphid or American blight, is an aphid in the superfamily Aphidoidea in the order Hemiptera. It is a true bug and sucks sap from plants.
Pulvinaria regalis is a species of scale insect in the family Coccidae. Although it is commonly known as the horse chestnut scale, it affects other trees besides horse chestnuts as well as many species of woody shrubs. Adults are normally all female and produce eggs by parthenogenesis. The insects are thought to have originated in Asia but arrived in Europe in the second half of the twentieth century.
Dysdercus koenigii is a species of true bug in the family Pyrrhocoridae, commonly known as the red cotton stainer. It is a serious pest of cotton crops, the adults and older nymphs feeding on the emerging bolls and the cotton seeds as they mature, transmitting cotton staining fungi as they do so.
Saissetia coffeae, known generally as hemispherical scale, is a species of soft scale insect in the family Coccidae. Other common names include the helmet scale and coffee brown scale.
Aspidiotus destructor, the coconut scale, is a species of armoured scale insect in the family Diaspididae, found in many tropical and subtropical parts of the world. It is a serious pest of coconut and banana, and attacks a range of other fruiting trees and ornamental plants.
Pyrilla perpusilla, commonly known as the sugarcane planthopper, is a planthopper in the family Lophopidae. It is native to Asia where it feeds on grasses and other plants and is a major pest of sugarcane and sorghum.
Protopulvinaria pyriformis, commonly known as the pyriform scale, is a species of soft scale insect in the family Coccidae. It is a pest of avocado and is found in many countries around the world where avocados grow.
Ceroplastes ceriferus, the Indian wax scale, is a species of scale insect in the family Coccidae. It is native to southern Asia and has spread to many other parts of the world.
Toumeyella parvicornis is a soft scale insect in the family Coccidae with a wide host range. It is commonly known as pine tortoise scale because of the characteristic appearance of the mature females, which look like tiny tortoises up to 1/4 inch in diameter.
Planococcus ficus, commonly known as the vine mealybug, is a species of mealybug, belonging to the family Pseudococcidae, native to tropical and subtropical regions. The vine mealybug is found in Europe, Northern Africa, Southern Africa, the Americas, and the Middle East. The vine mealybug is invasive to weedy plants in many different regions of the world.
Paratachardina lobata, the lobate lac scale, is a polyphagous lac scale insect, which damages trees and woody shrubs. It is native to India and Sri Lanka, but has been introduced to Florida where it is regarded as an invasive species.
Orchamoplatus citri, commonly known as the Australian citrus whitefly, is a whitefly species in the genus Orchamoplatus. It is found across Australia and New Zealand, primarily foraging on the leaves of citrus trees.
