First, look at the petiole. The petiole is the part of the leaf that supports the leaf and is not the stem although the stem does in fact support the entire leaf including the leaf lamina. Collectors commonly incorrectly call the petiole a "stem" but they are very different.

At the very top of the petiole you can run your fingers up near the blade and feel a 'bump'. That bump is known as the geniculum. A geniculum can be found on all Anthurium species even though it is sometimes not terribly distinct, especially in younger plants. It will always be there. The geniculum allows a leaf to rotate just like your elbow in order to orient itself to the light.

Anthurium species also possess a collective vein. The collective vein can be seen in your photo running from the lobes at the top of the blade around the outer edge. Some Anthurium have collective veins that run completely around the blade but others may not begin until the third or fourth lateral leaf vein emerges from the midrib and extends to the leaf margin (edge).

The midrib is the vein that runs down from the sinus to the tip of the leaf. The sinus is the area between the lobes.

Just like all Anthurium species this species is variable and often changes shapes as it matures from a juvenile to an adult

I tried to give a direct link to the page that would explain the difference in a stem and a petiole but the GardenWeb computer kept rejecting it. Please click on the link below and across down until you find the link to the page on "the difference in a stem and a petiole"

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