Green spotted puffer
Small brackish water pufferfish with a tiny genome
The green spotted puffer is a small fish from South and Southeast Asia. It lives in coastal rivers and mangroves. Scientists study it because its genetic code is very compact. Aquarists keep it for its bright colours, though it needs salty water.
- Has the smallest known vertebrate genome
- Flesh contains a virulent toxin
- Successfully bred in captivity in 2009
- Requires brackish water as an adult
- Primary diet consists of snails
What it is
This pufferfish has a green body covered in black spots. Its belly is white, while the fins and tail appear light green. Adults typically reach fifteen centimetres, though some grow to seventeen. Young fish start in brackish zones and move to fresher streams as they mature. They inhabit flood plains and rivers across their range.
Where it lives
You find this species across South and Southeast Asia. It lives in coastal freshwater areas, including rivers and streams. Mangrove forests provide important habitat for young fish. While adults tolerate fresh water, they survive longest in brackish or saltwater conditions. The environment shifts from low salinity for juveniles to high brackish levels for adults.
How it lives
These fish eat snails as their primary food source. Their diet also includes other molluscs, crustaceans, and some plants. Some individuals may scale-eat other fish. They are aggressive towards tank mates in captivity. In the wild, they navigate between freshwater and brackish zones. Their flesh holds a strong toxin that makes them unsafe for human consumption.
Breeding and life cycle
Scientists successfully bred this species in captivity in February 2009. The team at the University of Florida used a new variation of ovarian lavage. This technique helped overcome breeding challenges in controlled environments. Wild spawning habits involve moving between water types as the fish ages.
Fish and people
Aquarists value this fish for its striking appearance. It requires brackish water with a pH around eight to thrive. Keepers note its aggressive nature limits community tank options. It is not eaten due to toxic flesh but serves as bait. Researchers use it as a model organism because its genome is small yet contains as many genes as humans.
Questions people ask about Green spotted puffer
Is the green spotted puffer safe to eat?
No, you should not eat this fish. Its flesh contains a virulent toxin that is dangerous to humans. It has no value as a food fish, though it is sometimes used as bait.
What kind of water does this puffer need?
It starts life in brackish water and moves to high brackish conditions as an adult. In aquariums, it thrives best with a pH level of eight and specific gravity around 1.015.
Why do scientists study this fish?
It has the smallest known vertebrate genome, with about 340 million base pairs. Despite its small size, it has the same number of genes as humans, making it ideal for genetic research.
Good reading and sources
- Dichotomyctere nigroviridis on WikipediaEncyclopedia
- More photos on Wikimedia CommonsPhotos
- Wikidata recordOpen data
The facts on this page come from the Wikipedia article "Dichotomyctere nigroviridis", written by its contributors and used under the CC BY-SA 4.0 licence, and from its Wikidata record (CC0). EveryFish rewrote the text in its own words, with AI assistance, and compares every page with the article to make sure no passage is copied. It may be reused under the same CC BY-SA 4.0 licence with a link back.
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