Spicule
/ˈspɪkjul/
Definition
Spicule is a small, slender, pointed or needle-like structure found in certain plants or plant-associated biological structures. In botany, the term can describe minute bristles, scales, or rigid projections on plant surfaces or reproductive structures. Its exact form and function vary by species, but spicules are typically distinguished by their small size and narrow, pointed shape.
Botanical Significance
- Surface protection: In some plants, minute spicules contribute to a rough or abrasive surface texture and can make tissues less accessible to small herbivores or other organisms.
- Taxonomic value: The presence, shape, arrangement, and distribution of small projections can provide useful morphological characters for distinguishing closely related plant taxa.
- Reproductive structures: In some grasses and other flowering plants, related minute bristle-like structures occur on spikelets or floral parts, where their form can help identify species.
- Microscopic identification: Spicules may be examined with magnification when studying plant morphology, particularly when these small structures are difficult to
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