''Agasicles hygrophila'' is a species of
leaf beetle
The insects of the beetle family Chrysomelidae are commonly known as leaf beetles, and include over 37,000 (and probably at least 50,000) species in more than 2,500 genera, making up one of the largest and most commonly encountered of all beetle ...
known by the common name alligator weed flea beetle. It has been used successfully as an agent of
biological pest control against the
noxious aquatic plant known as
alligator weed
''Alternanthera philoxeroides'', commonly referred to as alligator weed, is a native species to the temperate regions of South America, which includes Argentina, Brazil, Paraguay and Uruguay. Argentina alone hosts around 27 species that fall with ...
(''Alternanthera philoxeroides'').
This beetle is native to South America but has been imported to areas where alligator weed is a problem. The adult beetle is 5 mm in length and black with yellow stripes on its
elytra
An elytron (; ; , ) is a modified, hardened forewing of beetles (Coleoptera), though a few of the true bugs (Hemiptera) such as the family Schizopteridae are extremely similar; in true bugs, the forewings are called hemelytra (sometimes alterna ...
. The female lays about 1,000 eggs in her six-week lifetime. Millimeter-long eggs are laid in rows on leaves, and the small yellow
larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
...
e emerge and eat the leaves. Adults also feed on the leaves. Defoliation of alligator weed mats kills the weed and clears the infested waterway. This beetle is established in much of the southeastern United States, where it lives on alligator weed only.
The beetle has been used as a biological control of alligator weed in
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
.
References
External links
Cornell Biological Control Profileon the
UF /
IFAS Featured Creatures Web site
Alticini
Beetles of South America
Arthropods of Argentina
Biological pest control beetles
Insects used for control of invasive plants
Beetles described in 1971
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