The scientific names of new species have to be submitted to the International Commission on Zoological Nomenclature for approval. They are most often two parters – genus first, then species (real proper taxonomy includes the surname of the describer and the date). Subspecies and variety names can lengthen the scientific name. You can read about cacti scientific names here – the rules more or less apply to all species.
The Latin or Greek may translate into something descriptive – or not, depending on the whim of the namer. So we have Tyranno (tyrant) saurus (lizard) rex (king) for the huge lizard dinosaur.
Still in the realm of dinosaurs, an American palaeontologist named one of his finds Dracorex (Draco = lizard; rex = king) hogwartsia (yes, in honour of Harry Potter’s school of wizardry; you can read about it here).
This may seem like a non-sequitur, but bear with me. Margaret from Copmanhurst, down south in dry sclerophyll eucalypt country, has kindly let me show her photos of what she thought was a fungus (thanks, Margaret!).
I suspected it was a slime mould, which is not a fungus at all but has its own taxonomic kingdom. A quick look at the ‘net and in reference books brought me no closer to a species name, so I sent off the photos to the Australian Museum Search and Discover department.
The slime mould was growing on a compost heap …
Six hours later, it looked like this …
Now here’s the fun bit. What would you call this charming specimen?
It’s DOG’S VOMIT SLIME MOULD!
The Australian Museum says:
Thank you for your enquiry. As you point out – the various slime moulds are hard to identify from the plasmodium stage. However, around suburban situations the two most commonly seen yellow slime moulds are Physarum polycephalum and Fuligo septica. As Physarum has a more stringy network appearance your slime mould appears to be Fuligo septica – commonly known as the Dog Vomit Slime Mould. The following weblinks will provide a little more detail:
http://botit.botany.wisc.edu/toms_fungi/june99.html
http://en.wikipedia.org/wiki/Fuligo_septica
Fuligo is Latin for “soot” or “black”; septica means something like “putrefying”.
The museum was impressed with her photos and asked if they could put them up on their “Curious and unusual identifications” web page. Well done, Margaret!
Update: Rebecca has a photo of the next (reproductive) stage of a slime mould here, plus links to click on for more information.
Further update: You can read how slime moulds used “externalised memory” here.


Fascinating! From your run down on how things are named, to the exposition of the Dog’s Vomit variety of slime mould, or is that Dog’s Vomit Slime variety of mould, or is that… well, you get my gist? Poor little doggy. Wonder what made it vomit?
This is the problem with common names – slime mould is not actually a mould but is its own non-mouldy “thing” (taxonomic kingdom Protista). But real moulds are fungi (kingdom Fungi). Slime moulds used to be classified as fungi, but taxonomists decided they needed their own kingdom.
Always good to see the transitional stage of Slime Molds.
Fun and games.
The Taxonomy is cloudy indeed. But what you have written is correct, as far as it goes – and I certainly do not want to try to take it any further.
Cheers
Denis
Me neither! I gave up on taxonomy at uni when I discovered that the difference between two spider species was whether the hairs on their legs turn clockwise or anticlockwise. I decided that was too much hard work! And to leave it to others who had more enthusiasm for tiny details.