Fern ally

Lycopodium annotinum 1127100195

Isoetes lacustris nf

Equisetum fluviatile Luc Viatour

Psilotum

Fern allies are a group of vascular plants that are not true ferns but share many similarities with them, including the dispersal of spores for reproduction. Fern allies include several distinct plant groups, such as clubmosses, spikemosses, and horsetails. These plants are often found in similar habitats as ferns, such as moist, shaded forests, but they can also inhabit a wide range of other environments.

Classification

The classification of fern allies has evolved over time with advances in botany and genetics. Traditionally, fern allies were grouped together in a single category, partly due to their non-seed-bearing nature. However, modern phylogenetic studies have shown that these plants do not form a monophyletic group (i.e., they do not share a single common ancestor that is not shared with any other group), leading to a reevaluation of their classification.

Major Groups

• Lycopodiophyta (clubmosses, spikemosses, and quillworts): This group is characterized by their microphyll leaves (leaves with a single vein) and includes some of the oldest living types of vascular plants.
• Equisetophyta (horsetails and scouring rushes): Members of this group have a unique jointed stem architecture and are known for their abrasive stems due to high silica content.
• Psilotophyta (whisk ferns): These plants are characterized by their simple, dichotomously branching stems and lack of true roots and leaves.
• Marattiophyta: While often considered true ferns, some classifications include Marattioid ferns as fern allies due to their unique characteristics and ancient lineage.

Morphology

Fern allies exhibit a wide range of morphological features, but they share some common traits with true ferns, such as the production of spores. Unlike ferns, which have large, divided fronds, fern allies often have simpler leaves or stems. The life cycle of fern allies also includes a dominant sporophyte stage, similar to that of true ferns, but their gametophyte stages can vary significantly in appearance and ecology.

Ecology

Fern allies are found in diverse habitats around the world, from tropical rainforests to arctic tundras. They play important roles in their ecosystems, such as stabilizing soil and providing habitat for other organisms. Some species of fern allies are adapted to extreme conditions, such as high altitudes or acidic soils, demonstrating a wide range of ecological niches.

Conservation

Like many plant groups, fern allies face threats from habitat loss, climate change, and pollution. Conservation efforts are important to preserve the biodiversity of fern allies, as they represent a significant component of the world's plant diversity and have important ecological roles in many ecosystems.

See Also

• Fern
• Vascular plant
• Spore
• Botany
• Phylogenetics