In+memoriam!+(Grevillea)

Plant genus: Grevillea Plant family: Proteaceae Common name: Spider flower Distribution: Popular garden plant, endemic of Australia but easily found also in other temperate and subtropical climates. Shape: Small shrub that can reach up to 1.5m in height. Flowers: Small red flowers, clustered together in an average of 57 per inflorescence (Fig 1.)

Average morphology measures (Fig 2): -total flower: 4.80cm -anther: 0.11cm -style: 3.80cm -stigma: 0.22cm -petal: 1.82cm

Figure 1. Grevillea inflorescence Figure 2. Flower parts

Nectar information: -Average nectar content per flower: 10.58uL -Average nectar content per inflorescence: 603.06uL -% of sugar concentration in the nectar: 14.9% (to get an idea: Coke is 11%)

Pollen information: -Triangular shape (Fig. 3)

Figure 3. Pollen of Grevillea. The three apices of the triangle are the spots where the pollen tube is going to germinate.

The usual Grevillea pollinators are birds. This is because of the shape of the flower, that makes it easy for a bird to access the nectar located at the bottom inside of the flower. Also, the nectar is found in great amounts, suitable for an animal bigger than an insect.

Extra observations: pollen from Clivia was found (Fig 4). This was probably due to a visit from a pollinator which had previously visited another plant. Visits from various pollinators often end up mixing the pollen between different plants: this is not a problem for plants, since they are able to distinguish their microgametophytes from the ones of others.

Figure 4. Pollen of Clivia. It is possible to notice the openings.

REFERENCES

- Moore, P. 2005. A Guide to Plants of inland Australia.Reed New Holland Publishers, Sydney