''Aphis gossypii'' is a tiny insect, an
aphid ("greenfly") in the superfamily
Aphidoidea in the order
Hemiptera
Hemiptera (; ) is an order (biology), order of insects, commonly called true bugs, comprising over 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, Reduviidae, assassin bugs, Cimex, bed bugs, and shield bugs. ...
. It is a true bug and sucks sap from plants. It is a widely distributed pest of a variety of agricultural crops in the families
Cucurbitaceae,
Rutaceae and
Malvaceae.
Common names include cotton aphid, melon aphid and melon and cotton aphid.
Distribution
It is not known where this species originated, but it is now found in tropical and temperate regions throughout the world except extreme northern areas. It is common in North and South America, Central Asia, Africa, Australia,
Brazil, East Indies, Mexico and Hawaii and in most of Europe. It is cosmopolitan in habitat. It thrives outdoors in southern Europe but survives only under glass in northern Europe.
In the former Soviet Union it is found up to 54°N.
Morphology
The wingless female cotton aphid has an ovoid body about two millimetres long in varying shades of green. The legs are yellow, as are the
antennae which are three quarters of the length of the body. The apices of the
femora,
tibia and
tarsi are black. The cylindrical black
siphunculi
The cornicle (or siphuncule) is one of a pair of small upright backward-pointing tubes found on the dorsal side of the 5th or 6th abdominal segments of aphids. They are sometimes mistaken for cerci. They are no more than pores in some species.
...
are wide at the base and one fifth of the body length. The winged female has a fusiform body. Its head and thorax are black, the abdomen yellowish-green with black lateral spots and the antennae are longer than those of the
apterous
Aptery is the anatomical condition of an animal completely lacking any kind of wings. An animal with this condition is said to be apterous.
Most animal species belong to and are phylogenetic descendants of apterous taxa. These groups are said to ...
female.
The nymphs vary in colour, being shades of green, tan and gray. They often have a dark head, thorax and wing pads and the distal portion of the abdomen is usually dark green. The body appears dull because it is dusted with wax secretions. The oval eggs are yellow when first laid but soon turn glossy black.
[University of Florida](_blank)
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In the southern half of the US, as far north as Arkansas, sexual reproduction of the cotton aphid is not important. Females continue to produce offspring without mating so long as the weather is favourable for feeding and growth.