Atlantic Sergeant Major
Abudefduf saxatilis
Scissortail Sergeant
Abudefduf sexfasciatus
About
The scissortail sergeant is a common damselfish of Indo-Pacific reefs, growing up to 19 cm. It often gathers in large groups over a single coral head.
Also known as: scissortail sergeant major, stripe-tailed damsel-fish, six-banded sergeant-major, scissor-tail sergeant
- Length
- 19 cm
- Depth
- up to 20 m
How to tell it apart
Look for a white damselfish with five bold black bars down its sides and two dark stripes running along the top and bottom of the tail fin, unlike similar sergeants that lack the double tail stripe.
Appearance
The body is white with five broad black vertical bars, giving it a striped look. Its tail has two dark horizontal bands running along the top and bottom lobes, which is where the "scissortail" name comes from.
Habitat
This fish lives on coral reefs, from 1 to 20 m deep. Adults stay close to the reef, often in loose groups hovering above a coral head, while younger fish spend time out in open water before settling down.
Breeding
Males are polygamous and will collect eggs from up to 12 females in their territory, then guard the eggs alone until they hatch. Males cycle between a mating phase, when they turn gold to attract females, and a parental phase of guarding the eggs a few days later. Females often lay their eggs together in one male's territory, which spreads out the risk of the eggs being eaten.
Did you know?
Males of this species change colour to gold during the mating phase to attract females, then lose the gold colour a few days later once they switch to guarding the eggs.
Log it in Into the Blue
Describe what you saw and we name it, then keep every species you find in your Oceandex.
