This page is from the Northern Ontario Plant Database website.
These botanical shapes, normally applied to leaves, are also applicable to phyllaries, bracts and petals. The width of each basic shape can be described as narrowly- or widely-, depending on the degree of modification from the standard shapes. Plants with leaves that have more than one shape are called heterophyllous.
Linear - long and narrow, with essentially parallel margins.
Lanceolate - widest below the middle of the blade and 3 to 6 times as long as wide.
Ovate - widest below the middle of the blade and about 1.5 to 2 as long as wide.
Elliptic - widest at the middle of the blade, with curved margins and pointed apex and base.
Oblong - rectangular, with nearly parallel margins, about 2 times as long as wide.
Oval - widest at the middle of the blade, with curved margins and rounded apex and base.
Rhombic - diamond-shaped, widest at the middle and with straight margins.
Deltoid - triangular, shaped roughly like an equilateral triangle.
Oblanceolate - reverse lanceolate, widest above the middle of the blade.
Spatulate - spoon-shaped, basically oblanceolate, but with a narrow (attenuate) base.
Obovate - reverse ovate, widest above the middle of the blade.
Orbicular - circular, with rounded sides.
Scale-like - reduced in size, flat and sharp-pointed or blunt.
Subulate - awl-shaped, narrow and pointed, rounded in cross section.
Acicular - needle-like, very narrow and pointed, rounded in cross section.
Runcinate - oblanceolate with lacerate margins.
Fan-shaped - a leaf with the blade spreading out in a semi-circle.
Peltate - a leaf with the petiole attached near the centre of the undersurface of the blade.
Cordate - heart-shaped, with a pointed apex and 2 rounded basal lobes.
Obcordate - reverse heart-shaped, with a narrow base and 2 rounded apical lobes.
Reniform - kidney-shaped, with a broad rounded apex and 2 rounded basal lobes.
Sagittate - a leaf with pointed basal lobes directed downwards or inwards.
Hastate - a leaf with pointed basal lobes divergent or directed outwards.
Auriculate - a leaf with small rounded (ear-like) lobes at the base.
Lyrate - lyre-shaped, basically oblanceolate, with 2 or > pairs of smaller lower lobes.
Panduriform - fiddle-shaped, basically oblanceolate, with 2 small lower lobes.
© Tom Lebsack 2021
Banner photo: Along the Middle Swan River in Summit County