Studying Lichens

By

Doing Some Research

At The Melitensia

At The University Of Malta.

Lichens are common organisms that grow in

the most unusual places including bare rock and

walls, even in urban areas.

Where do we find lichens?Where do we find lichens?

About 200 lichens have been

recorded in the Maltese islands

How many different types of lichens can be found in the Maltese Islands?How many different types of lichens can be found in the Maltese Islands?

Lichens are unusual because each species is

made up of two organisms, a fungus and an alga, living intimately

together.

What are Lichens? They are surely not plants. So what are they?What are Lichens? They are surely not plants. So what are they?

Their relationship gives lichens the ability to survive under harsh conditions where no other organism can

survive.

Is their relationship a beneficial one?Is their relationship a beneficial one?

In some cases the fungus and alga which make up a lichen can be

found living separately in nature but, in many cases, the two organisms have become so

dependent on each other that one cannot survive without the other.

Can they live separetely?Can they live separetely?

Lichens do not have leaves or roots and absorb nutrients

directly through their surface. This leaves them susceptible to air pollutants which ac cu mulate

in their body without being eliminated.

Lichens and PollutionLichens and Pollution

Lichens can tolerate different concentrations of pollutants with some species dying at lower levels

than others. This makes lichens excellent biomonitors and many

species are used to indicate levels of environmental pollutants.

Why are we using lichens as monitors of pollution in this project?Why are we using lichens as monitors of pollution in this project?

Many species of lichens are eaten especially in

times of famine despite the fact that they can be

difficult to digest.

Are Lichens used as a form of food?Are Lichens used as a form of food?

Many species also contain mildly toxic

compounds, although few species are

poisonous.

Are Lichens poisonous?Are Lichens poisonous?

Some species are used to produce

dyes including the pH indicator litmus.

Are Lichens used for anything else?Are Lichens used for anything else?

SYSTEMATIC LIST OF ENDEMIC LICHEN SPECIES (can only be found in Malta)

1.Biatora fusco-nigrescens Jatta

2.Caloplaca marmorata Bagi cephaloidea Jatta in Sommier & Caruana 

Gatto

3.Caloplaca melitensis Jatta

4.Caloplaca pyracea (Ach.) Th. lactea Mass. macrocarpa Jatta

5.Collema meliteum Jatta conglomeratum Jatta

6.Graphina sophistica Nyl. melitense Jatta in Sommier & Caruana Gatto

7.Lecaniella alocyza Mass. flavidula Jatta

8.Lecanora sublentigera Jatta

9.Lecidea pertusariicola Jatta

10.Scolicosporium doriae Baglietto decussatum Jatta

11.Thalloedema mammillare (Fr.) Mass. pulchella Jatta

12.Thalloedema paradoxum Jatta

Caloplaca sp., a distinctive yellow lichen which covers bare rock

Ramalina durieui, found mostly on thin branches of pine (Pinus halepensis) and

cypress (Cupressus sempervirens)

Another 'leafy', cypress-loving species

This lichen appears to prefer dead bark of the pine tree

A white lichen on a rock