Dykning med Eldkoraller

Lanta Marina Liv | Milleporidae

Eldkorallarter är sessila (stationära, fixerade på en plats) Medusozoa, som kan producera kalciumkarbonatskelett och bilda kolonier, i likhet med hårda koraller, men de är inte riktiga koraller. Vi kan se enorma kolonier av eldkoraller när vi dyker från Koh Lanta runt Koh Rok.

Vissa arter är viktiga revbyggare, och flera arter av Millepora kan mycket snabbt bygga upp skelett av kalciumkarbonat. Dessa skelett är täckta av otaliga porer som innehåller polyperna. Varje matpolyp är omgiven av många defensiva stickpolyper som innehåller batterier av nematocystceller. Vid beröring tränger nematocysterna in i människans hud och injicerar ett kraftigt gift, vilket skapar den 'eldliknande' brännskadan.

Förutom att fånga byten med sina stickande nematocystpolyper får brandkoraller näring via sitt speciella symbiotiska förhållande med alger som kallas zooxanthellae, på samma sätt som hårdkorallerna.

2 arter finns på denna sida:

Branching Fire Coral (Millepora tenella)
Leaf Fire Coral (Millepora platyphylla)

Branching Fire Coral

(Millepora tenella)

Millepora tenella @ Koh Rok

Branching Fire Coral is commonly seen at all of the dive sites around Koh Lanta. A Branching Fire Coral colony begins by encrusting a surface to form a base, and then growing outward in multiple branches.

This is a fast growing species and is capable of taking over large areas of a reef.

The colonies consist of thick, golden brown branches, with the growth zones at the tips of the branches being white.

Branching Fire Coral @ Koh Rok

Branching Fire Coral feed on plankton, and similar to true corals, due to their symbiotic relationship with zooxanthellae, they are subject to bleaching if the colourful zooxanthellae algae leave the polyps due to high sea water temperatures for example.

Fire corals can deliver a very painful burn-like sting - do not touch fire coral, you will regret it.

Leaf Fire Coral

(Millepora platyphylla)

Millepora platyphylla @ Koh Rok

Leaf Fire Coral grows vertically in leaf or plate-like branches. This species likes to grow on the top of the reef, in turbulent water (in the wave action zone) and enjoys strong sunlight which is necessary for the symbiotic zooxanthellae algae’s photosynthesis.

Leaf Fire Coral @ Koh Rok

Leaf Fire Coral is densely branched and provides shelter and home for a wide range of other species, including shrimp, frogfish, moray eels, and other small fish seeking refuge from potential predators.

As with other Fire Corals, Leaf Fire Coral can deliver a very nasty poisonous burn if touched.

Fire corals grow quickly and can push out other hard coral species to dominate some areas of a reef. Whilst this can be destructive, it can also contribute toward the survival of hard corals during Crown of Thorns outbreaks, as Crown of Thorns sea stars tend to avoid Fire Corals.