What is a "semilichen"?
Me: *sighs* this is some Jan Vondrák nonsense, isn't it? *Googles* yep, called it.
Ok ok, It's not really nonsense, it's just that Jan has a tendency to publish papers that make my life more complicated as a lichenologist than it already is. He loves breaking the field and introducing new concepts and terms and questions to be asked. He's a really cool, really smart, really nice guy who knows his shit, but he's become a bit of an inside joke in our lab group, to the point that when stuff gets complicated we yell "JAAAAN!!!" in the style of "KAHHHHN!" from Star Trek.
Anyhow, a semilichen (or an alcobiosis as it is sometimes called), is a community of fungi and photosynthesizing organisms like green algae or cyanobacteria that grow together and seem to have some sort of symbiotic association, but are not as like, close? or closed? as a true lichen symbiosis. It is something that falls juuuust short of being a lichen by being less structured and less like, obvious. Usually, it looks like a sort of undifferentiated slime. So where is the line between semilichen and lichen? A lichen has a thallus--a "body" which has specialized structures made up of more-or-less organized fungal hyphae and photobiont cells. Semilichens are more of a general mixture of fungi and photobiont cells without structure or organization. A lichen is a casserole, and a semilichen is a soup. It's not a perfect metaphor but its all I got.
This is all still new, emerging science mostly being done by a small group of researchers, but it is all very exciting and I hope we can watch the development of this field in real time!
Semilichen, an unjustly neglected symbiotic system between green biofilms and true lichens
Alcobiosis, an algal-fungal association on the threshold of lichenisation
