FLORA OF ICELAND elements: Lycopodium selago = Huperzia selago, fir clubmoss

Lycopodium selago = Huperzia selago; The Fir Clubmoss has a characteristic fingerlike growth of stems branching form the base. The vegetative leaves and sporophyl-bearing leaves are similar. Thus the plant does not have a sporohpyllic cone like some other clubmosses. The absence of trailing stems ("runners") is also a characteristic that can be used to identify this primitive fern on Iceland. It grows in heatherlands and amongst rocky places.
How to recognize common Iceland clubmosses:
1) No trailing stems and no "cones on top of stems", leaves needle-shaped with smooth margins :
   Lycopodium selago (= Huperzia selago), the fir clubmoss; this card
else: go to 2)

2) No trailing stems but sporophyls (leaves with spore-forming organs in the axis of leaf and stem) on top of stems, leaves are toothed:
  Selaginella selaginoides, Lesser Clubmoss
else: go to 3)

3) Long prostrate stems ("runners") and sporophyllia on top of ascending brances;
3a) leaves of ascending branches pressed on the stem:
   Lycopodium alpinum, Alpine Clubmoss
3b) leaves of ascending branches spreading from stem:
   Lycopodium annotinum, Interrupted Clubmoss

Very rare on Iceland is Lycopodium clavatum - of western Europe. It is much like Lycopodium annotinum but characteristically has a stem segment between the vegetative parts and the sporophyl-bearing part which has very small leaves, making this intersegment stem look almost nude. Split on top of this segment are two sporangial stems (hence the name clavatum).