Elater

At that time, the elaters uncoil to extend out from the spore and will catch air currents.

The fact that they are extended only when conditions are dry means that successful spore dispersal is more likely.

In the liverworts also known as hepaticopsida [example Riccia,Marchantia], elaters are cells that develop in the sporophyte alongside the spores.

They are complete cells, usually with helical thickenings at maturity that respond to moisture content.

In the hornworts, elaters are branched clusters of cells that develop in the sporophyte alongside the spores.

The mature strobili of a horsetail ( Equisetum arvense ).
A cross section through a horsetail strobilus, showing spores with elaters.
Spores and two elaters of the liverwort Ptilidium .