---
title: Longfins (Plesiopidae)
scientific_name: Plesiopidae
common_name: Longfins
rank: Family
published: 2024-11-19T18:41:51.573Z
updated: 2026-08-03T21:03:17.269Z
tags: Longfins, Plesiopidae, Red Sea, Marine Life, Diving
url: https://redseacreatures.com/taxon/fishes/bony-fishes/longfins
---

# Longfins (*Plesiopidae*)

## Quick facts

- **Rank:** Family
- **Scientific name:** Plesiopidae
- **Body shape:** Oval - Egg-shaped body, deeper than it is thick - damselfishes, surgeonfishes.
- **Species listed here:** 4

## How to recognise this group

- small, robust body, 5-15 cm long
- cryptic, mottled colouration with spots or stripes
- hovers head-down or upside-down under ledges
- inhabits caves, crevices, under ledges

Longfins (family Plesiopidae) are small, robust-bodied fishes, typically measuring 5 to 15 cm (2 to 6 in) in length. They often possess large eyes and prominent, elongated pelvic fins, which give the group its common name. Their cryptic colouration provides camouflage, ranging from mottled browns and greys to iridescent purples and blues, frequently displaying spots or stripes across their bodies.

These reclusive fish inhabit caves, crevices, and under ledges on coral and rocky reefs, from shallow reef flats down to approximately 40 m (130 ft). Longfins typically live solitarily or in pairs, often seen hovering upside-down or head-down beneath overhangs. When disturbed, they dart quickly into shelter. They are predators, primarily feeding on small crustaceans and other benthic invertebrates. Despite their widespread distribution, their shy behaviour often leads to them being overlooked by divers.


## Species (4)

- [Comet Longfin (Calloplesiops altivelis)](https://redseacreatures.com/taxon/fishes/bony-fishes/longfins/comet-longfin)
- [Moustache Longfin (Plesiops mystaxus)](https://redseacreatures.com/taxon/fishes/bony-fishes/longfins/moustache-longfin)
- [Red Sea Spiny Basslet (Acanthoplesiops cappuccino)](https://redseacreatures.com/taxon/fishes/bony-fishes/longfins/red-sea-spiny-basslet)
- [Redtipped Longfin (Plesiops coeruleolineatus)](https://redseacreatures.com/taxon/fishes/bony-fishes/longfins/redtipped-longfin)

---

*Source: [Red Sea Creatures](https://redseacreatures.com/taxon/fishes/bony-fishes/longfins)*
*Updated: August 3, 2026*