Mottled Water Hyacinth Weevil Neochetina eichhorniae Warner (Insecta: Coleoptera: Curculionidae)
“Bird’s nest” fungi (Nidulariaceae)
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Neochetina eichhorniae
mottled water hyacinth weevil
Eichhornia crassipes

How to Cite

Kariuki, Eutychus, and Carey Minteer. 2021. “Mottled Water Hyacinth Weevil Neochetina Eichhorniae Warner (Insecta: Coleoptera: Curculionidae)”. EDIS 2021 (1), 5.


Sometimes referred to as the ‘mottled water hyacinth weevil’, Neochetina eichhorniae Warner is a weevil that attacks the invasive, aquatic plant, water hyacinth, Eichhornia crassipes (Mart.) Solms. Water hyacinth is considered one of the most destructive plants in aquatic ecosystems in the United States and, as a result, is listed in both the federal noxious weed list and Florida’s list of prohibited aquatic plants. Neochetina eichhorniae is host specific and causes substantial damage to water hyacinth, making it a valuable biological control agent for this invasive weed in many parts of the world. The insect was first introduced into the United States from Argentina in 1972, when scientists released the insect in Broward County, Florida, to manage water hyacinth (Perkins 1973). Since then, the insect has been introduced in more than three dozen countries worldwide (Winston et al. 2014). Post-introduction studies indicate the insect substantially suppresses the growth of water hyacinth, significantly reducing biomass, flowers production, and water surface coverage (Grodowitz et al. 1991, Center et al. 1999, Tipping et al. 2014, Nesslage et al. 2016) and the need for herbicide applications (Haag 1986).
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Center for Agriculture and Bioscience International. 2019. Eichhornia crassipes (water hyacinth). Available online at: (Accessed 21 May 2019)

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Center TD, Dray Jr FA, Jubinsky GP, Leslie AJ. 1999. Water hyacinth weevils (Neochetina eichhorniae and N. bruchi) inhibit water hyacinth (Eichhornia crassipes) colony development. Biological Control 15: 39-50.

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Forno IW. 1981. Effects of Neochetino eichhorniae on the growth of water hyacinth. Journal of Aquatic Plant Management 19: 27-31.

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Grodowitz MJ, Stewart RM, Cofrancesco AF. 1991. Population dynamics of water hyacinth and the biological control agent Neochetina eichhorniae (Coleoptera: Curculionidae) at a southeast Texas location. Environmental Entomology 20: 652-660.

Haag KH. 1986. Effective control of water hyacinth using Neochetina and limited herbicide application. Journal of Aquatic Plant Management 24: 70-75.

Nesslage GM, Wainger LA, Harms NE, Cofrancesco AF. 2016. Quantifying the population response of invasive water hyacinth, Eichhornia crassipes, to biological control and winter weather in Louisiana, USA. Biological Invasions 18: 2107-2115.

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Perkins BD. 1973. Release in the United States of Neochetina eichhorniae Warner, an enemy of water hyacinth. Proceedings of the 26th. Annual Meeting Southern Weed Science Society. 368 pp. [Abstract]

Stark JD, Goyer RA. 1983. Life cycle and behavior of Neochetina eichhorniae Warner (Coleoptera: Curculionidae) in Louisiana: a biological control agent of water hyacinth. Environmental Entomology 12: 147-150.

Tipping PW, Martin MR, Pokorny EN, Nimmo KR, Fitzgerald DL, Dray FA, Center TD. 2014. Current levels of suppression of water hyacinth in Florida USA by classical biological control agents. Biological Control 71: 65-69.

Van TK, Center TD. 1994. Effect of paclobutrazol and water hyacinth weevil (Neochetina eichhorniae) on plant growth and leaf dynamics of water hyacinth (Eichhornia crassipes). Weed Science 42: 665-672.

Winston RL, Schwarzländer M, Hinz HL, Day MD, Cock MJW, Julien MH. 2014. Biological Control of Weeds: A World Catalogue of Agents and Their Target Seeds, 5th ed. FHTET-2014-04. USDA Forest Service Publication, Morgantown, WV. 838 pp.

Wright AD, Center TD. 1984. Predicting population intensity of adult Neochetina eichhorniae (Coleoptera: Curculionidae) from incidence of feeding on leaves of water hyacinth, Eichhornia crassipes. Environmental Entomology 13: 1478-1482.

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