Term:
Impressed
Impressed
Definition:
Sunken below the surface as if pressed in; e.g., some leaf or seed veins in relation to the rest of the leaf or seed surfaces.
Sunken below the surface as if pressed in; e.g., some leaf or seed veins in relation to the rest of the leaf or seed surfaces.
Notes:
In neotropical Lecythidaceae usually referring to impressed secondary leaf veins on the abaxial leaf blade surface and impressed seed veins. Impressed veins are not common in Lecythidaceae but are of taxonomic importance when they do occur. The differences among salient, prominent, prominulous, plane, and submerged are based on the degree of elevation, e.g., between the top of a vein and the surface of the organ of which it is a part. These features grade into one another but generally speaking a salient vein is one that projects 0.5 to several millimeters above the surface, a prominent vein is one that is distinct and raises between 0.1 and 0.4 mm above the surface, and a prominulous vein is one that is raised so little that it is only perceived when a finger nail is run along the blade at a right angle across it. If nothing blocks the fingernail, the vein is plane and if a depression is perceived it is impressed. If a vein is not seen, it is said to be submerged in the tissue. In neotropical Lecthidaceae, this terminology is mostly applied to the the veins of leaves and seeds.
In neotropical Lecythidaceae usually referring to impressed secondary leaf veins on the abaxial leaf blade surface and impressed seed veins. Impressed veins are not common in Lecythidaceae but are of taxonomic importance when they do occur. The differences among salient, prominent, prominulous, plane, and submerged are based on the degree of elevation, e.g., between the top of a vein and the surface of the organ of which it is a part. These features grade into one another but generally speaking a salient vein is one that projects 0.5 to several millimeters above the surface, a prominent vein is one that is distinct and raises between 0.1 and 0.4 mm above the surface, and a prominulous vein is one that is raised so little that it is only perceived when a finger nail is run along the blade at a right angle across it. If nothing blocks the fingernail, the vein is plane and if a depression is perceived it is impressed. If a vein is not seen, it is said to be submerged in the tissue. In neotropical Lecthidaceae, this terminology is mostly applied to the the veins of leaves and seeds.