Monophlebidae is a family of

scale insect 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 ...

s commonly known as the giant scales or monophlebids. They occur in most parts of the world but more genera are found in the

tropics The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

than elsewhere.UDSA Agricultural Research Service
The cottony cushion scale, ''

Icerya purchasi ''Icerya purchasi'' ( common name: cottony cushion scale) is a scale insect that feeds on more than 80 families of woody plants, most notably on ''Citrus'' and ''Pittosporum''. Originally described in 1878 from specimens collected in New Zealand ...

'', is a serious commercial pest on many families of woody plants, including ''

Citrus ''Citrus'' is a genus of flowering plant, flowering trees and shrubs in the rue family, Rutaceae. Plants in the genus produce citrus fruits, including important crops such as Orange (fruit), oranges, Lemon, lemons, grapefruits, pomelos, and lim ...

''. It has spread worldwide from Australia.

Taxonomy

At one time, Monophlebidae was considered to be a subfamily of

Margarodidae The Margarodidae (illegitimately as Margodidae) or ground pearls are a family of scale insects within the superfamily Coccoidea. Members of the family include the Polish cochineal and Armenian cochineal (genus ''Porphyrophora'') and the original ...

. However the family Margarodidae showed great morphological and

biological Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary in ...

variation and Maskell first recognised Monophlebidae as a separate family in 1880. The giant scales are morphologically diverse but they appear to be a

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

group.

Hosts

Giant scales occur on a wide range of host plants but most of these are trees or woody shrubs.

Description

Giant scales have an elongated oval body; many species grow to a length of one centimetre long and the African species '' Aspidoproctus maximus'' achieves 35 mm long. The adult females of the family have six dark coloured legs and conspicuous antennae. Most genera have a waxy coating but some do not. Various species have some form of ovisac or marsupium.

Life cycle

Giant scales infest the stems, branches and leaves of their host plant. They mostly have four female and five male

instar An instar (, from the Latin '' īnstar'', "form", "likeness") is a developmental stage of arthropods, such as insects, between each moult (''ecdysis''), until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or ass ...

s. The prepupal instar are mobile, unlike most members of other scale families. They may have wing buds and the legs and antennae are well developed.

Genera

*'' Afrodrosicha'' *'' Aspidoproctus'' *'' Buchnericoccus'' *'' Conifericoccus'' *'' Corandesia'' *'' Crypticerya'' *''

Drosicha ''Drosicha'' is a genus of true bugs belonging to the family Margarodidae The Margarodidae (illegitimately as Margodidae) or ground pearls are a family of scale insects within the superfamily Coccoidea. Members of the family include the Polish ...

'' *'' Drosichoides'' *'' Echinicerya'' *'' Etropera'' *'' Gigantococcus'' *'' Gueriniella'' *'' Gullania'' *'' Hemaspidoproctus'' *''

Icerya ''Icerya'' is a genus of scale insects in the family Monophlebidae. It is named after physician-naturalist Dr. Edmond Icery of British Mauritius. Hermaphroditism Hermaphroditism In reproductive biology, a hermaphrodite () is an organism ...

'' *'' Insulococcus'' *'' Jansenus'' *'' Labioproctus'' *'' Laurencella'' *'' Lecaniodrosicha'' *'' Llaveia'' *'' Llaveiella'' *'' Matesovia'' *'' Melaleucococcus'' *'' Misracoccus'' *'' Modicicoccus'' *'' Monophlebidus'' *'' Monophleboides'' *'' Monophlebulus'' *'' Monophlebus'' *'' Nautococcus'' *'' Neogreenia'' *'' Neohodgsonius'' *'' Nietnera'' *'' Nodulicoccus'' *'' Palaeococcus'' *'' Paracoelostoma'' *'' Paramoandesia'' *'' Peengea'' *'' Perissopneumon'' *'' Protortonia'' *'' Pseudaspidoproctus'' *'' Sishania'' *'' Steatococcus'' *'' Tessarobelus'' *'' Vrydagha'' *'' Walkeriana''

References