''Brachycaudus helichrysi'' is a species of
aphid
Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A t ...
first described by the German naturalist
Johann Heinrich Kaltenbach in 1843.
Its
common names include leaf curl plum aphid,
and leaf-curling plum aphid, and it is a serious pest of
plum and
damson
The damson () or damson plum ('' Prunus domestica'' subsp. ''insititia'', or sometimes ''Prunus insititia''),M. H. Porche"Sorting ''Prunus'' names" in "Multilingual multiscript plant names database, University of Melbourne. Plantnames.unimelb.e ...
trees.
Description
The
viviparous
Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the ...
wingless females have an oval or pear-shaped body and grow to a length of up to . Early in the season they are brownish but later they are yellowish-green. The
antennae are pale green and short, about half the length of the body. There is no dark, shining patch on the dorsal surface of the abdomen, a fact which distinguishes it from the otherwise similar thistle aphid (''
Brachycaudus cardui''). The cauda (tail-like elongation) is bluntly rounded, the legs are pale except for the extremities, and the
cornicle
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.
...
s are pale-coloured, short and flanged.
[
]
Biology
''Brachycaudus helichrysi'' overwinters as fertilised eggs which hatch during the winter or early spring, before the plum and damson trees on which they are laid come into leaf. The fundatrices (viviparous parthenogenetic females produced on the primary host) feed at first at the base of buds but as the buds begin to expand, they move on to softer tissues, and later on to the new shoots and underside of the foliage. By May, some winged forms are beginning to appear and these fly to secondary hosts, such as Asteraceae
The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae w ...
, '' Chrysanthemum'' and ''Trifolium
Clover or trefoil are common names for plants of the genus ''Trifolium'' (from Latin ''tres'' 'three' + ''folium'' 'leaf'), consisting of about 300 species of flowering plants in the legume or pea family Fabaceae originating in Europe. The genus ...
'', where they found new colonies
In modern parlance, a colony is a territory subject to a form of foreign rule. Though dominated by the foreign colonizers, colonies remain separate from the administration of the original country of the colonizers, the '' metropolitan state'' ...
. The colonies on the primary host gradually die out. Further generations develop on the secondary hosts and in the autumn, winged forms fly back to the primary host. Here sexual forms develop, mating takes place and eggs are laid on twigs and spurs of the plum and damson trees.[ Natural enemies include ]ladybirds
Coccinellidae () is a widespread family of small beetles ranging in size from . They are commonly known as ladybugs in North America and ladybirds in Great Britain. Some entomologists prefer the names ladybird beetles or lady beetles as they ...
, lacewings
The insect order Neuroptera, or net-winged insects, includes the lacewings, mantidflies, antlions, and their relatives. The order consists of some 6,000 species. Neuroptera can be grouped together with the Megaloptera and Raphidioptera in the ...
, soldier beetle
The soldier beetles (Cantharidae) are relatively soft-bodied, straight-sided beetles. They are cosmopolitan in distribution. One of the first described species has a color pattern reminiscent of the red coats of early British soldiers, hence the ...
s and hoverflies
Hover flies, also called flower flies or syrphid flies, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring at flowers; the adults of many species feed mainly on nectar and pollen, while ...
.[
]
Damage
''Brachycaudus helichrysi'' is a serious pest of stone fruits. It forms dense colonies on the underside of the leaves of the primary host causing curling,[ twisting and distortion of the foliage, the shedding of flowers and the dropping of young fruit.]plum pox
Plum pox, also known as sharka, is the most devastating viral disease of stone fruit from the genus ''Prunus''. The disease is caused by the plum pox virus (PPV), and the different strains may infect a variety of stone fruit species including pea ...
.[
]
References
{{Taxonbar, from=Q14086568
Macrosiphini
Insects described in 1843
Insect pests of millets