Spleen Fern

Classification and Distribution

The spleen fern (Asplenium ceterach, synonymous with Ceterach officinarum) is a species of the family Aspleniaceae, commonly known as strip ferns. It is found in Central Europe, North Africa, Asia, and parts of Eastern Europe.

### Conservation Status
In Germany, the spleen fern is under nature conservation due to its protected status.

Morphology

The plant reaches a height of 6 to 20 cm and forms a dense cluster with a thick root. The leaves are linear to linear-lancet in shape, lackluster, and feather-sliced, with nine to twelve semi-circular to egg-shaped sections on both sides. The underside of the leaf is covered with permanent, light brown, egg-shaped spray sheds that cover each other like a tile roof.

### Adaptation to Drought
During drought, the leaves curl up and protect the plant from evaporation by forming a protective layer on their scalloped side.

Reproduction

The spores reach maturity in June to August. The plant is a poikilohydric species, meaning it can survive with alternating periods of moisture and dryness, often referred to as "resurrection plants."

### Distribution
The spleen fern has been found in the following countries:

* North Africa: Algeria; Egypt; Libya; Morocco; Tunisia
* Asia: Iran; Israel; Jordan; Lebanon; Syria; Kazakhstan; Kirgystan; Tajikistan; Uzbekistan; Pakistan
* Europe: Ireland; United Kingdom; Austria; Belgium; Czech Republic; Germany; Hungary; Netherlands; Poland; Slovakia; Switzerland; Ukraine (Crimea); Albania; Bosnia and Herzegovina; Croatia; Greece; Italy

Note: The provided sources had some inconsistencies, but I've done my best to merge the information into a coherent article.