The lion kings

You’ll not hear these lions roar (Jane in Cape Town says lions don’t roar but merely cough, and she should know – Attenborough and Disney, you lied!), but they can certainly do you an injury if you mess with them.

The spines are venomous as distinct from poisonous, which is something different. The Smithsonian says:

Some people use the words interchangeably because once in the body, the chemicals do similar damage, attacking the heart, brain or other vital targets. But the terms do mean very different things. Traditionally, venomous creatures bite, sting or stab you to do their damage, while you have bite or touch poisonous critters to feel their effects. That means venomous organisms need a way in, like fangs or teeth.

In fact, lionfish are distinctly edible as long as you avoid the spines. Several countries have invasive populations creating environmental havoc in their seas, but have made an industry of catching and serving them in restaurants – a win-win situation in those places.

Those spines are defensive and can give you an extremely painful, but not fatal, prod.

NOAA says:

The lionfish’s sharp, slender spines are located on the dorsal, anal and pelvic fins. The venom is a combination of protein, a neuromuscular toxin, and a neurotransmitter called acetylcholine. The sting causes intense pain, redness and swelling around the wound site. Although the worst of the pain is over after an hour or two, some people report pain and tingling sensations around the wound for several days or weeks. On rare occasions, when the venom spreads to other parts of the body, people may experience headaches, chills, cramps, nausea, and even paralysis and seizures.

Now back to Woody Head, where Peter Scharf took these photos. The first three are of the zebra lionfish, Dendrochirus zebra. Its distribution in Australia is Shark Bay, WA to Sydney, NSW. (Distributions are given in a clockwise direction around the country.)


Zebra lionfish, Dendrochirus zebra; photo Peter Scharf

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Naked (gills) at Woody Head

Peter has been busy with his underwater camera. He found some nudibranchs while snorkelling at Woody Head, northern NSW. Many thanks to Peter for letting me use his photos.

I’m sure you know already but, in case you don’t, the name  ‘nudibranch’ means ‘naked gill’. Nudis are (usually) tiny molluscs that are brightly coloured and apparently taste ghastly to potential predators (at least according to Ed Ricketts, who had a chew). They have been measured at 6 mm to 31 cm (0.25″ to 12″ for you imperialists).

National Geographic explains:

They are carnivores that slowly ply their range grazing on algae, sponges, anemones, corals, barnacles, and even other nudibranchs. To identify prey, they have two highly sensitive tentacles, called rhinophores, located on top of their heads. Nudibranchs derive their coloring from the food they eat, which helps in camouflage, and some even retain the foul-tasting poisons of their prey and secrete them as a defense against predators.

Nudibranchs are simultaneous hermaphrodites, and can mate with any other mature member of their species. Their lifespan varies widely, with some living less than a month, and others living up to one year. …

Some nudibranchs are solar-powered, storing algae in their outer tissues and living off the sugars produced by the algae’s photosynthesis.

The first is Hypselodoris maritima …

Hypselodoris maritima

Hypselodoris maritima

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The racing stripe flatworm

The Woody Head rock platform and bay have many great marine animals easily seen by snorkellers. I’ve written many posts about this area; you can use the search function on this blog to track them down.

An example is the beautiful marine flatworm, Pseudoceros sp. [Update: Gary Cobb of thinks it is an undescribed species of Pseudoceros.]

Pseudoceros bifurcus

Pseudoceros sp.; all photos by Peter Scharf

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