Bug FAQMottled Waterhyacinth Weevil
Neochetina eichhorniae · Order: Coleoptera · Family: Brachyceridae
Also called: Weevil
The mottled waterhyacinth weevil is about 3.5 mm long, not counting its head and antennae. It is brownish-gray with distinctive brown mottling. Native to Argentina and nearby South American regions, it has been introduced to Florida in 1972 and later to other U.S. states and countries for biological control of water hyacinth.
Source: Wikipedia
How to recognize it
The weevil’s body is brownish-gray with characteristic brown mottling.
Source: Wikipedia
How to get rid of it
- The species was first released in Florida in 1972 as a biological control agent for water hyacinth.
- Successful control in the Everglades led to its introduction in other U.S. states and countries such as East African Lake Victoria.
Source: Wikipedia
What it eats
Adults feed on water hyacinth leaves and petioles, leaving feeding scars; larvae tunnel inside petioles and the plant crown.
Source: Wikipedia
Life cycle
Its life cycle lasts about three to four months, depending on conditions.
Source: Wikipedia
Where it comes from
It originates from Argentina and surrounding areas of South America.
Source: Wikipedia
Where it is found in the US
Recorded in 5 of 51 states and DC. Most records: Florida, Louisiana, California, Texas, Maine.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
How big is the mottled waterhyacinth weevil?
Adults are about 3.5 mm long, not counting the head and antennae.
Source: Wikipedia
What does this weevil look like?
It is brownish-gray with distinctive brown mottling.
Source: Wikipedia
Where does this weevil come from?
It is native to Argentina and nearby South American regions.
Source: Wikipedia
How is it used to control water hyacinth?
It was introduced to Florida in 1972 and later to other areas to feed on and damage water hyacinth, helping reduce the invasive plant.
Source: Wikipedia
Same family (Brachyceridae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Neochetina_eichhorniae
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-28 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-28.