Archive · 11 Nov 2025
Rare Half-Male, Half-Female Spider Discovered in Thailand
Scientists found a very special spider in Thailand that is like two spiders in one!
It's called Damarchus inazuma.
This spider is half-male and half-female.
One side of its body is bright orange and has bigger fangs, showing its female side.
The other side is grey and has different features, showing its male side.
This is called gynandromorphism and it's super rare, especially in this type of spider.
Researchers were very surprised to find it!
They think this happened when the spider was very young and its body started to grow.
They are not sure if it's poisonous, but it might be to tiny insects, because other spiders like it have venom.
A new spider species, Damarchus inazuma, with both male and female characteristics was discovered in Thailand.
The spider exhibits gynandromorphism, with its body perfectly divided into a male side and a female side, displaying distinct physical traits and colors.
This is the first recorded instance of gynandromorphism in the Bemmeridae family and one of only three known cases in the mygalomorph group.
Researchers from Chulalongkorn University identified the spider after a local naturalist posted a photo online.
While not formally studied for venom, the spider likely possesses venom, at least for small insects, based on observations of related species and its aggressive displays.
- Who
- Researchers from Chulalongkorn University and local naturalists
- What
- Discovered a new species of spider, Damarchus inazuma, exhibiting gynandromorphism (half-male, half-female traits)
- When
- Recently
- Where
- A forest area near Nong Rong, Thailand
- Why
- The spider is a new species with a rare biological condition, gynandromorphism.
- Species Name
- Damarchus inazuma
- Location
- Nong Rong, Thailand
- Phenomenon
- Gynandromorphism
- Family
- Bemmeridae
- Group
- Mygalomorph
- Publication
- Zootaxa