Umbrella Pad
Descended from Bulbus Fossancoris
Zone 4, Zone 4a
80 cm (diameter of pad, stem length varies from 2 - 10 meters)
B. rigistylus is a polyph that is specialized in the shallow intertidal zone of Zone 4/Zone 4a.
Adaptations: The most notable adaptation that B. rigistylus has developed is its now rigid stems. This is due to the tissue within now being more specialized for support, using turgor pressure to do so. The bulk of B. rigistylus is supported by a "main stem" while "support stems" provide additional support and balance. These stems developed their rigidity in response to wave action washing older generations onto beaches. Another adaptation is the larger size of the the photosynthetic pad, allowing it to collect more sunlight. This pad is positioned about a meter above the maximum height of high tides, preventing the polyph from spending time underwater. A more minor adaptation is that there are now small "nubs" that attach the polyph's seeds more firmly to the fronds that they grow on which reduces the number of seeds removed prematurely. This is due to the "nubs" that increase the surface area that attaches the seeds to the stem.
Feeding: B. rigistylus uses its large photosynthetic pad to create sugars from the sun. Its roots uptake water and nutrients.
Reproduction: The umbrella pad drops weighted seeds from secondary tendrils. These tendrils retain their ancestral ability of being able to extend to the substrate and develop into additional support stems.