---
title: Red Sea Nymph Cardinalfish (Cercamia spio)
scientific_name: Cercamia spio
common_name: Red Sea Nymph Cardinalfish
taxon: Cardinals
published: 2024-11-08T13:17:08.511Z
updated: 2026-08-18T22:19:00.580Z
tags: Red Sea Nymph Cardinalfish, Cercamia spio, Cardinals, Red Sea, Marine Life, Diving
url: https://redseacreatures.com/taxon/fishes/bony-fishes/cardinals/red-sea-nymph-cardinalfish
---

# Red Sea Nymph Cardinalfish (*Cercamia spio*)

## Quick facts

- **Group:** Cardinals (*Apogonidae*)
- **Depth:** 10-30 m
- **Diet:** Carnivore
- **Activity:** Nocturnal
- **Rarity:** Rare
- **Habitat:** Reef caves and deep crevices
- **Reproduction:** Mouthbrooder
- **Endemic:** Endemic to the Red Sea

## How to recognise it

- small, slender, pale pinkish cardinalfish
- deep inside caves and crevices, rarely in the open
- large eye for the head
- under 5 cm

Look this fish up in the world register of marine species and it is not there.

That happens, and it does not mean the animal is imaginary. A scientific name has to be published in a particular way to count, and the databases that track those names are compiled by people working through a literature that is scattered across two centuries and a dozen languages. Names get missed, names sit in journals nobody indexed, and names published in regional works can take decades to reach a global register. This species is recorded in the printed references for this sea and absent from the register, and the gap is a bookkeeping problem rather than a biological one.

It is a useful thing to know when using any catalogue, this one included. A database is a record of what has been entered into it, and the sea does not consult it.

The fish is a small, slender, pale cardinalfish of caves and deep crevices between about ten and thirty meters, endemic to this sea, and rarely seen because it does not come out of cover.

---

*Source: [Red Sea Creatures](https://redseacreatures.com/taxon/fishes/bony-fishes/cardinals/red-sea-nymph-cardinalfish)*
*Updated: August 18, 2026*