What does sp stand for?

[vugc]

Hi all what does the sp. behind some of the plant names stand for? eg echinodorus sp,tonina sp...

[budak]

It means that the plant has been ascertained to be in a particular genus (e.g. Echinodorus, Tonina, Ludwigia), but no scientist (taxonomist to be precise) has gotten down to scientifically describing the unique features, morphology etc that distinguish the species from others in the same genus. The privelege of naming the species falls on the scientist who publishes the first Description of the organism. The reason why there are so many unknown "sp." is that so many thousands of new species of creatures and plants are being discovered (faster than science can catalogue them) in recent years. Unfortunately, many of these creatures may also vanish before they even get a proper name, as their habitats are under great threat, especially those in Southeast Asia.

[vugc]

That's enlightening, thanks. By the way,budak what's the growth rate for marsilea crenata,it's not demanding on anything at all rite...light,co2,fert?

[budak]

you are welcome. For Marsilea, I find it's a relatively slow-growing plant, but spreads out steadily. If you had bought the emmersed form, it will take a few weeks to fully develop all submersed foliage. SOmetimes algae can be a problem, so the infested individual leaves should be snipped off without cutting off the main horizontal stem. I am growing it in a low light (1.5 wpg), high CO2 and medium fert level tank, but am also trying it out in a no-CO2, minimal fert, low light tank.