sweetpotato weevil
Cylas formicarius (Fabricius, 1798)


The origin of Cylas formicarius is not definitely known, but it is thought it may have originated in Africa or India.
Life Cycle
Adults are ant-like, shiny, blue-black, snout beetles whose "waist" and legs are bright orange-red. They are about 0.24 in. (6 mm) long. Larvae are legless, white to cream colored with a pale brown head. Larvae are about 0.35 in. (9 mm) long. Breeding is continuous throughout the winter, especially in potatoes in storage. Eggs are laid singly in small cavities eaten out in the stem or tuber. Eggs hatch in less than a week and larvae feed inside for two to three weeks. Pupation occurs in the potatoes. The pupal stage lasts about a week to 10 days. There can be as many as eight generations per year.
Cylas formicarius is found throughout the coastal plain of the Southeast from North Carolina to Texas. It also is found in Hawaii and Puerto Rico, and widely around the world in tropical regions.
Control Efforts
Insecticides, cutural practices and biological controls are being used or researched for control of this pest.

Selected Images

Taxonomic Rank

Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Atelocerata
Class: Hexapoda (including Insecta)
Infraclass: Neoptera
Subclass: Pterygota
Order: Coleoptera
Suborder: Polyphaga
Infraorder: Cucujiformia
Superfamily: Curculionoidea
Family: Brentidae
Subfamily: Cyladinae
Genus: Cylas
Subject: Cylas formicarius (Fabricius, 1798)

Synonyms and Other Names

Related Scientific Names:
Cylas elegantulus (Summers) (Synonym)