---
title: Sidespot Cardinalfish (Apogonichthyoides heptastygma)
scientific_name: Apogonichthyoides heptastygma
common_name: Sidespot Cardinalfish
taxon: Cardinals

published: 2024-11-08T12:50:41.883Z
updated: 2025-11-25T13:58:09.000Z
tags: Sidespot Cardinalfish, Apogonichthyoides heptastygma, Cardinals, Red Sea, Marine Life, Diving
url: https://redseacreatures.com/taxon/fishes/bony-fishes/cardinals/sidespot-cardinalfish
---

# Sidespot Cardinalfish (*Apogonichthyoides heptastygma*)

**Taxon:** Cardinals (*Apogonidae*)  


The Sidespot Cardinalfish (Apogonichthyoides heptastygma) is a tropical, marine species predominantly inhabiting reef ecosystems. This species reaches a maximum length of 3.3 cm and is distinguishable by the presence of ocelli on its sides. Additionally, the anterior edge of the first dorsal fin is characteristically dark, succeeded by a prominent white stripe. 

The Sidespot Cardinalfish engages in mouthbrooding behavior, with distinct pairing observed during courtship and spawning phases. This species is endemic to the Western Indian Ocean, specifically the Red Sea.

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*Source: [Red Sea Creatures](https://redseacreatures.com/taxon/fishes/bony-fishes/cardinals/sidespot-cardinalfish)*
*Updated: November 25, 2025*