APPW key feature pages

Petiole morphology

The leaves on some aquatic plants have petioles with distinctive morphological features.

 

with mucous covering

 

bulbous, thickened with aerenchyma

 

bearing spines

 

morphology otherwise

APPW key feature pages

• Aroid or aster?
• Aroids only - spadix and spathe type
• Asteraceae only - floret composition
• Asteraceae only - ray floret petal size and shape
• Duckweed (Lemnaceae) frond roots
• Duckweed (Lemnaceae) frond shape
• Flowering plant family
• Flower color
• Flower pedicel
• Flower symmetry
• Geographic origin
• Inflorescence - number of flowers
• Inflorescence - peduncle
• Inflorescence position
• Flowering plant or non-flowering plant
• Bract(s) subtending inflorescence
• Inflorescence type
• Leaf apex
• Leaf base
• Leaf - degree of dissection
• Leaf dissection - type
• Leaf distribution along stem
• Floating leaf shape in profile
• Leaf heterophylly
• Number of leaflets or lobes
• Leaf length (leaf or leaflet blade)
• Leaf margin
• Leaf midvein spines
• Leaf overall morphology
• Leaf or petiole bands or septae
• Leaf phyllotaxis (arrangement along stem)
• Leaf presence
• Leaf shape - rosette plants
• Leaf shape
• Leaf thickness
• Leaf venation
• Leaf attachment to stem
• Petiole length
• Petiole presence
• Petiole spines
• Petiole morphology
• Liverwort thallus shape
• Size and appearance of petals, tepals, or perianth segments
• Perianth constitution
• Perianth fusion
• Number of petals, tepals, or perianth segments
• Bulb or corm morphology
• Plant appearance (attached plants only)
• Plant attachment
• Plant habit - aquatic
• Plantlet production
• Plant structures for spreading vegetatively
• Plant type
• Plant type - flowering plants
• Root type and presence
• Spongy aerenchyma
• Stem appearance
• Stem presence
• Stem surface ribbing
• Stem shape in cross section
• Stipules present?
• Trapping organs