Blackbordered dascyllus
Dascyllus marginatus
- Usual depth2–18 m
- Water temperature15–30 °C
- Best monthsApril, August, and October
- How commonRare
Photo credit: (c) Georgina Jones, some rights reserved (CC BY-SA), uploaded by Georgina Jones · CC BY-SA · iNaturalist
About this species
Dascyllus marginatus, the marginate dascyllus or Red Sea dascyllus, is a damselfish endemic to the Western Indian Ocean. It is a site attached fish that lives in corals, usually Stylophora pistillata and species of Acropora. In these corals it hides at a moment of danger and sleeps at night. It feeds on zooplankton that drifts with the current, and grows to a size of 6 cm in length. Dascyllus marginatus lives in groups of 2-25 individuals, and while foraging for food around their home coral, group members keep separated and stable foraging spaces.
Text from the Wikipedia article “Dascyllus marginatus”, licensed CC BY-SA 4.0. Read the article
Where and when
Where it has been recorded
Worldwide
Loading the map
Best months
Worldwide (open data)
- January: 8 records
- February: 12 records
- March: 11 records
- April: 20 records
- May: 8 records
- June: 11 records
- July: 19 records
- August: 30 records
- September: 19 records
- October: 31 records
- November: 11 records
- December: 19 records
Depth and water temperature
Depth
Mostly recorded at 2–18 m · Deepest record: 22 m
Water temperature
Recorded in surface water of 15–30 °C
Photos
(c) Juraj Ahel, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Dr. Thomas Dörner, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist 
no rights reserved · CC0 1.0 · iNaturalist 
(c) Gergely Nigg, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Pauline Walsh Jacobson, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Libby Keatley, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Pauline Walsh Jacobson, some rights reserved (CC BY) · CC BY · iNaturalist
Names and classification
- English
- Blackbordered dascyllus, blackbordered dascyllus, grey humbug, marginate dascyllus, Red Sea Dascyllus, Twobanded Humbug
Names in 3 more languages
- Spanish
- Damisela del Mar Rojo
- French
- Demoiselle de mer Rouge
- Thai
- ปลาสลิดหินหน้าสั้น
Other scientific names: Pomacentrus marginatus
Similar species
Banded dascyllusDascyllus aruanus
Reticulate dascyllusDascyllus reticulatus
DominoDascyllus trimaculatus
black damselfishDascyllus flavicaudus
Blacktail DamselfishDascyllus melanurus
Cow pilotAbudefduf saxatilis
Sources and credits
Names and taxonomy: WoRMS (CC BY 4.0) and the GBIF Backbone (CC BY 4.0). Photos: iNaturalist observers, each under the licence shown (CC0, CC BY or CC BY-SA).
- Depth, temperature, months and maps: records from OBIS and GBIF under CC0 or CC BY.
- Descriptions: Wikipedia, licensed CC BY-SA, each linked to its article.
- Conservation status as published by GBIF (IUCN Red List).
- 218 open-data records from 1828 to 2023.
- Species data updated October 26, 2026.
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