Drosera

Lore & Background

The trapping and digestion mechanism usually employs two types of glands: stalked glands that secrete sweet mucilage to attract and ensnare insects and enzymes to digest them, and sessile glands that absorb the resulting nutrient soup. Small prey, mainly insects, are attracted by the sweet secretions. Upon touching these, the prey become entrapped by sticky mucilage, and death usually occurs within 15 minutes. The plant secretes esterase, peroxidase, phosphatase and protease enzymes to dissolve the insect. All species of sundew are able to move their tentacles in response to contact with edible prey, a response known as thigmonasty.

Reader's Guide

Drosera holds a significant place in botanical history as one of the first genera to have carnivory confirmed in plants, largely through the work of Charles Darwin. The genus demonstrates a remarkable diversity of growth forms—including temperate, subtropical, pygmy, tuberous, and tropical species—adapted to nutrient-poor environments across every continent except Antarctica. The carnivorous mechanism, involving sticky mucilage and enzyme secretion, allows these plants to supplement mineral nutrition from insect prey. The phylogenetic relationships within the genus remain under study, with some sections like Drosera being polyphyletic, indicating a need for taxonomic revision. Sundews continue to be a model for studying plant movement (thigmonasty) and adaptation to extreme habitats.

Did You Know?

• Charles Darwin performed the first experiments confirming carnivory in plants using Drosera rotundifolia.
• The name 'sundew' derives from Latin ros solis meaning 'dew of the sun'.
• Some species, like D. burmanni and D. sessilifolia, can bend their outer tentacles inward in a matter of seconds after contact with prey.
• Pygmy sundews form gemmae for asexual reproduction and have dense hairs to protect from intense Australian sun.