Selaginellaceae

The Sélaginellacées are a family of plants belonging to the division of the Lycophyte S.

General description

Sélaginellacées are plants with very diverse ports. They generally have a stem ramified by successive junctions, bearing of the roots and many small whole sheets laid out on four rows along the branches. The sheets of this family are characterized by the presence, at their base, of a Ligule on the higher face.

Reproduction

Fructifications (Sporange S) are inserted into the armpit of the sheets (= sporophylle) and form a quadrangular ear as a whole (= strobile). Sélaginellacées present a Hétérosporie and a Hétéroprothallie:
  • the sporanges carried by the sporophylles at the base of the strobile contain four large Spore S (up to 0,5 mms in diameter), they are the macrospores (regarded as females). One speaks about macrosporangia.
  • the sporanges carried by the sporophylles in top of the strobile contain very many microscopic spores, they are the microspores (regarded as males). One speaks about microsporanges.

The microspores are partitioned in a microprothalle (= male Prothalle) formed of only one vegetative cell and a Anthéridie. This prothalle remains included in the spore.

The macrospores are partitioned in a macroprothalle (= prothalle female) limited to the wall of the spore. This prothalle has of Rhizoïde S and several Archégone S.

Medium of life

They are species living primarily in the tropical areas with some species in moderate areas.

Kind

Sélaginellacées include/understand one kind today which counts approximately 700 species:

External bonds

Selaginellales

Selaginellaceae

  • Flora laurentienne: Family of the '' Selaginellaceae ''

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