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St. Andrew's Cotton Stainer (Dysdercus andreae)

Detailing the identifying qualities of the St. Andrew's Cotton Stainer, including physical features and territorial reach.

 Updated: 12/20/2017; Authored By Staff Writer; Content ¬©

  St. Andrew's Cotton Stainer  
Picture of St-Andrews-Cotton-Stainer-Bug
Picture of St-Andrews-Cotton-Stainer-Bug Picture of St-Andrews-Cotton-Stainer-BugPicture of St-Andrews-Cotton-Stainer-Bug

Originally a pest of cotton plants, St. Andrew's Cotton Stainer has moved on to another important cash crop in the sunshine state.

St. Andrew's Cotton Stainers are a type of Red Bug known for marking or staining the fruit it feeds on. The torso has a white diagonal, or tilted cross, like that of St. Andrew on the Scottish flag. Its bright red body has black wing tips, two black spots in the middle of the body near the center of the cross, and a black triangle near the pronotum ('shoulders') smudged with red in its center. Nymphs are commonly seen with adults on the same plant and have a plump abdomen with white lines running across it. Each white line has a tiny black dot on the midline of the insect.

Historically, Cotton Stainers attacked young cotton bolls, which left to mature become the tufts of cotton that is harvested from cotton plants in order to make fabric and cotton balls. Their feeding habits streaked the young white cotton a yellowish brown color that never washed out. This staining ruined harvests on a grand scale, establishing the genus as an agricultural pest. This species can cause young cotton bolls to stain and remain small in size. Both nymphs and adults groups pierce fruit with their beaks and drink the juices inside. They are increasingly seen on fruit trees and may be to blame for orange drop, a consequence of their feeding on oranges which results in the fruit completely falling off the tree the same day. Spraying soapy water on affected plants may deter them and removing weeds, debris and other hiding places on the ground removes their winter shelters.

Picture of the St. Andrew's Cotton Stainer
Picture of the St. Andrew's Cotton Stainer

St. Andrew's Cotton Stainer Information

Category: True Bug
Common Name: St. Andrew's Cotton Stainer
Scientific Name: Dysdercus andreae

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Insecta
    Arrow graphic Order: Hemiptera
     Arrow graphic Family: Pyrrhocoreidae
      Arrow graphic Genus: Dysdercus
       Arrow graphic Species: andreae

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 8 mm to 12 mm (0.312 inches to 0.468 inches)
Identifying Colors: red, black, white
Additional Descriptors: oranges, drop, cross, diagonal, triangle, dots, smear, stain, flying, pest, harmful

North American Territorial Reach (Though Not Limited To): Florida

A Note About Territorial Reach: Keep in mind that an insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above. Insects are driven by environmental factors, food supplies and mating patterns and do not nescessarily work within hard-and-fast territorial lines like we humans do.

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