Lethocerus medius

Lethocerus medius · Order: Hemiptera · Family: Belostomatidae

No source yet on danger. We have no source yet on whether it bites, stings or damages anything.
Lethocerus medius
Photo: Laura Gaudette, CC BY

Lethocerus medius is a giant water bug belonging to the family Belostomatidae. Adults are about 5 to 6 cm long, with females a bit larger than males. It lives in freshwater habitats across Central America, parts of the southern United States, and several Caribbean islands.

Source: Wikipedia

Size

Males grow to about 49 to 58 mm and females to about 62 to 63 mm in length.

Source: Wikipedia

Where it comes from

Its native range includes Central America, the southern United States, and several Caribbean islands.

Source: Wikipedia

Where it is found in the US

Recorded in 6 of 51 states and DC. Most records: Texas, Arizona, New Mexico, Illinois, Nevada, Oklahoma.

Darker = more records. Counts are museum and citizen-science records, not population size.

Source: GBIF

Months it is reported in the US

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Source: GBIF

More photos

Lethocerus medius photo 2
Photo: Michelle W. （鍾偉瑋）, CC BY
Lethocerus medius photo 3
Photo: Andrew Meeds, CC BY
Lethocerus medius photo 4
Photo: iNaturalist user, CC0
Lethocerus medius photo 5
Photo: johnyochum, CC BY

Same family (Belostomatidae)

American Giant Water BugAmerican Giant Water BugLethocerus americanusCan biteUhler's Giant Water BugUhler's Giant Water BugLethocerus uhleriBelostoma flumineumBelostoma flumineum

Sources

  • Wikipedia: https://en.wikipedia.org/wiki/Lethocerus_medius

Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia

Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-24.

How this page works

This is one bug's fact sheet. The colored box at the top says whether it is dangerous. Sections below cover how to recognize it, whether it is a pest, and how to deal with it. The US map shows which states have records; tap a state to see other bugs there.

Every fact on Bug FAQ comes from a named source (university extension sites, government agencies, GBIF, iNaturalist, Wikipedia). The source is linked next to each section. If we have no source for something, we leave it out.