Marine life encyclopaedia
A scientific reference to Red Sea biodiversity — for divers, researchers, and universities
Jeddah dive training — trainee reviewsSea conditions for diving
Species of the dayInvertebrates
Black Sea Cucumber
Holothuria nobilis
Holothuria (Microthele) nobilis, the black teatfish, is a species of sea cucumber in the genus Holothuria. The sea cucumber is found in the tropical waters of the Indo-Pacific ocean. It was first described by Emil Selenk…
Encyclopaedia sections
Open a section for the detailed guide with photos and scientific notes
Fish — Pisces
A Red Sea fish guide organised by families, with scientific names, conservation status, and biology.
Corals — Anthozoa
Hard and soft corals, reef biology, reef zones, bleaching causes, and documented responses.
Invertebrates
Molluscs, crustaceans, echinoderms, and jellyfish — including octopus, shrimp, starfish, and urchins.
Sharks — Selachii
Red Sea sharks including grey reef, hammerhead, and whale shark — behaviour, conservation, diver notes.
Turtles & Marine Mammals
Four sea turtles, dolphins, whales, and the dugong — large marine animals of the Red Sea.
Conservation
Climate change, coral bleaching, overfishing, and pollution — a report with IUCN context and sources.
Seagrass & Algae
Food-web foundation — seagrass that feeds dugong and turtles, and algae that produce much of Earth’s oxygen.
Ocean Depth Zones
From the intertidal shore to the hadal trench — depth zones and typical animals in each.
Scientific Glossary
Glossary of marine biology, oceanography, taxonomy, and conservation terms.
Photo Gallery
Photo gallery of the encyclopaedia — browse by species, search, and open full-size images.
Full Species Search
Search the whole encyclopaedia by Arabic, English, or scientific name, with section filters.
Marine weather (planning)
Guidance scores for wind, waves, and sea-surface temperature at selected sites — updated via Open-Meteo.
Compare Species
Pick two species to compare photos, names, and scientific summaries side by side.
Saved species
Save species from search or compare before a dive. Without an account they stay on this browser only.
Marine Quiz
An interactive quiz on identification, facts, habitat, and conservation — for students and divers.
The Red Sea — scientific notes
Why the Red Sea is an exceptional marine system scientifically
Hottest and saltiest
Among the hottest and saltiest seas (about 21–32°C, salinity 36–41‰), which produced distinctive adaptations.
Slowly widening
It widens by about 2 cm per year along a tectonic rift — among the youngest ocean basins on Earth.
Evolutionarily isolated
Isolation from the Indian Ocean for millions of years produced high fish endemism, reported up to about 17%.
No major rivers
No large river flows into it, so it is often clearer and lower in organic pollution than many seas.
Heat-tolerant reefs
Red Sea reefs are often more bleaching-resistant than many others because of evolutionary heat exposure — a research focus.
Still being described
Dozens of species are described each year; a substantial share of the seabed remains poorly surveyed.
Marine habitats
Each Red Sea habitat hosts a different community — the six main systems
Reef flat
The most light- and heat-exposed zone. Shallow Acropora, damselfish, and clownfish dominate. Animals here tolerate unusual temperature and salinity swings.
Reef crest
The breaking-wave zone — among the highest diversity and productivity. Strong Acropora and massive corals grow here.
Fore reef
The most diverse part of the reef, sloping from the crest into deeper water. Hard and soft coral families mix; most reef fishes concentrate here.
Mesophotic zone
A dim zone (30–150 m) whose diversity is still being described. Some corals here are less exposed to surface heat — a possible refuge.
Pelagic zone
Open water away from the seabed. Whale sharks, manta rays, barracuda, and trevally use this column. Currents bring plankton that support large food webs.
Sandy bottom
Sand looks empty but holds life — bluespotted rays bury here, octopus hide, sea cucumbers roam, and starfish forage.
Reference scientific databases
Sources this encyclopaedia used to compile and classify the information
Fish database
FishBase
The world’s largest fish database — more than 35,000 species
Non-fish marine life database
SeaLifeBase
A database of marine animals other than fishes
World Register of Marine Species
WoRMS
The global register of marine species names and taxonomy
Corals of the World
Corals of the World
A specialised scientific reference on reef-building corals
IUCN Red List
IUCN Red List
Threatened species assessments and conservation status
Ocean Biodiversity Information System
Ocean Biodiversity IS
Geographic records of marine species worldwide
Encyclopedia of Life
Encyclopedia of Life
A scientific encyclopaedia of living organisms
Reef guide
ReefGuide
A large reef-fish guide with photos and descriptions
Taxonomy method
This encyclopaedia follows modern Linnaean binomial taxonomy, with reference to:
- WoRMS (World Register of Marine Species) for accepted scientific names
- FishBase & SeaLifeBase for biological data
- IUCN Red List for conservation status (2024)
- Corals of the World for coral taxonomy
- Peer-reviewed papers in marine journals
Note: taxonomy is revised continuously — scientific names can differ between sources after recent revisions.
See these animals yourself
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