Lasius japonicus

Lasius japonicus · Order: Hymenoptera · Family: Formicidae

Can irritate skin. It can irritate skin with its formic acid spray.

Source: Wikipedia

Lasius japonicus
Photo: Jonghyun Park, CC BY

These ants are mostly black with a hint of white on the rear part of their bodies. They spray formic acid both to defend themselves and to attack, which can cause skin irritation. They are common in East Asia and are known for tending aphids to harvest honeydew.

Source: Wikipedia

Where it lives

They tend aphids closely, protecting them in exchange for honeydew.

Source: Wikipedia

What it eats

They collect honeydew secretions from aphids.

Source: Wikipedia

Where it comes from

They are commonly found throughout East Asia.

Source: Wikipedia

More photos

Lasius japonicus photo 3
Photo: Jonghyun Park, CC BY
Lasius japonicus photo 4
Photo: Jonghyun Park, CC BY
Lasius japonicus photo 5
Photo: donwerth-chikamatsu, CC BY

Questions people ask

What do Lasius japonicus ants look like?

They are mostly black with a slight white tint on the rear part of their bodies.

Source: Wikipedia

Can they irritate my skin?

Yes, they spray formic acid which can cause skin irritation.

Source: Wikipedia

Where are these ants found?

They are common throughout East Asia.

Source: Wikipedia

What do they eat?

They tend aphids and harvest the honeydew the aphids secrete.

Source: Wikipedia

Same family (Formicidae)

Eastern Black Carpenter AntEastern Black Carpenter AntCamponotus pennsylvanicusCan damage your homeRed Imported Fire AntRed Imported Fire AntSolenopsis invictaCan stingAmerican Winter AntAmerican Winter AntPrenolepis imparisArgentine AntArgentine AntLinepithema humileNuisance, not dangerousImmigrant Pavement AntImmigrant Pavement AntTetramorium immigransCan stingOdorous House AntOdorous House AntTapinoma sessileCan damage your home

Sources

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

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

Text written 2026-10-23 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-23.

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