---
title: "Longfin Damselfish"
description: "Stegastes diencaeus — Peixes. Stegastes diencaeus, the longfin damselfish, is a damselfish in the family Pomacentridae from the Western Atlantic."
canonical: https://animalchecklist.com/pt/animal/longfin-damselfish
last_updated: 2026-09-20
---

# Longfin Damselfish

> Stegastes diencaeus — Peixes. Stegastes diencaeus, the longfin damselfish, is a damselfish in the family Pomacentridae from the Western Atlantic.

- Scientific name: *Stegastes diencaeus*
- Category: `fish` (Peixes)
- Habitats: `sea` (Mar e costa)
- iNaturalist observations: 1415
- Wikidata: [Q2209857](https://www.wikidata.org/wiki/Q2209857)
- iNaturalist taxon: [128185](https://www.inaturalist.org/taxa/128185)

## Names

- en: Longfin Damselfish
- es: Jaqueta miel
- fr: Demoiselle noire

## Countries with the most observations

MX (185), CW (89), HN (71), JM (61), BZ (59), KY (51), BS (40), US (37), VI (34), CU (30), PR (27), GP (24)

## Summary

Stegastes diencaeus, the longfin damselfish, is a damselfish in the family Pomacentridae from the Western Atlantic. It occasionally makes its way into the aquarium trade. It grows to a size of 12.5 cm in length. Longfin damselfish have been reported to have a mutualistic relationship with mysid shrimp of the species Mysidium integrum. The interaction is described as a form of domestication with the shrimp providing nutrients for the algae farms the fish feed on and the fish providing protection from predators.

Text: Wikipedia (en), CC BY-SA 4.0 — https://en.wikipedia.org/wiki/Stegastes_diencaeus

## Photo

![Longfin Damselfish](https://animalchecklist.com/img/animals/longfin-damselfish/medium.jpg)

Photo: Jean-Paul Boerekamps · CC0 · inaturalist — https://www.inaturalist.org/observations/75593299

## Machine access

`GET https://animalchecklist.com/api/v1/animals/longfin-damselfish?lang=pt` — see [openapi.json](https://animalchecklist.com/openapi.json).