FLORA OF ICELAND elements: Lycopodium annotinum (Spinulum annotinum), interrupted clubmoss, Lyngjafni

Lycopodium annotinum also known as Spinulum annotinum; The Interrupted Clubmoss can easily be recognized from all other common Icelandic clubmosses by the rather glossy (pointed) leaves spreading from the stems. The plant forms fertile branches growing vertically from long horizontal runners. The fertile branches can grow up to about 30cm - much longer than the fertile shoots of Lycopodium alpinum. These fertile shoots are not or only little branched at the base. Another difference is that L. annotinum is that the vegetative leaves are spreading. Like the alpine clubmoss the interrupted clubmoss the fertile leaves are organized in terminal spikes.
Some identify two subspecies being Lycopodium annotinum ssp. annotinum and Lycopodium annatinum ssp. alpestre. Others though argue that there are intermediate forms so splitting the species in two subspecies is untenable. The difference that "alpestre" has more appressed leaves and are less dentate. It is most common in the northern, north-western and north-eastern coastal regions. On Iceland it is known as Lyngjafni.