Glossary of leaf morphology

From Wikipedia, the free encyclopedia
Chart illustrating leaf morphology terms

The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular or irregular, may be smooth or bearing hair, bristles or spines. For more terms describing other aspects of leaves besides their overall morphology see the leaf article.

The terms listed here all are supported by technical and professional usage, but they cannot be represented as mandatory or undebatable; readers must use their judgement. Authors often use terms arbitrarily, or coin them to taste, possibly in ignorance of established terms, and it is not always clear whether because of ignorance, or personal preference, or because usages change with time or context, or because of variation between specimens, even specimens from the same plant. For example, whether to call leaves on the same tree "acuminate", "lanceolate", or "linear" could depend on individual judgement, or which part of the tree one collected them from. The same cautions might apply to "caudate", "cuspidate", and "mucronate", or to "crenate", "dentate", and "serrate".

Another problem is to establish definitions that meet all cases or satisfy all authorities and readers. For example, it seems altogether reasonable to define a mucro as "a small sharp point as a continuation of the midrib", but it may not be clear how small is small enough, how sharp is sharp enough, how hard the point must be, and what to call the point when one cannot tell whether the leaf has a midrib at all. Various authors or field workers might come to incompatible conclusions, or might try to compromise by qualifying terms so vaguely that a description of a particular plant practically loses its value.

Furthermore, the use of these terms usually is not restricted to leaves only, but may be used in describing the morphology of many other parts of plants, e.g. bracts, bracteoles, stipules, sepals, petals, carpels or scales.

Leaf structure[]

Leaves of most plants include a flat structure called the blade or lamina, but not all leaves are flat, some are cylindrical. Leaves may be simple, with a single leaf blade, or compound, with several leaflets. In flowering plants, as well as the blade of the leaf, there may be a petiole and stipules; compound leaves may have a rachis supporting the leaflets. Leaf structure is described by several terms that include:

Bipinnate leaf anatomy with labels showing alternative usages
A ternate compound leaf with a petiole but no rachis (or rachillae)
Image Term Latin Description
Leaf morphology Bifoliolate.png bifoliolate Having two leaflets[1]
geminate
jugate
Leaf morphology Bigeminate.png bigeminate Having two leaflets, each leaflet being bifoliolate
Leaf morphology bipinnate.png bipinnate bipinnatus The leaflets are themselves pinnately-compound; twice pinnate
Leaf morphology Biternate.png biternate With three components, each with three leaflets
Leaf morphology odd pinnate.png imparipinnate With an odd number of leaflets, pinnate with a terminal leaflet (the opposite of paripinnate)
odd-pinnate
Leaf morphology even pinnate.png paripinnate Pinnate with an even number of leaflets, lacking a terminal leaflet (the opposite of imparipinnate)
even-pinnate
Leaf morphology Palmately compound.png palmately compound palmatus Consisting of leaflets all radiating from one point
pinnately compound pinnatus Having two rows of leaflets on opposite sides of a central axis, see imparipinnate and paripinnate
Leaf morphology Acute.png simple Leaf blade in one continuous section, without leaflets (not compound)
Leaf morphology trifoliolate.png ternate ternatus With three leaflets
trifoliate trifoliatus
trifoliolate trifoliolatus
Leaf morphology tripinnate.png tripinnate tripinnatus Pinnately compound in which each leaflet is itself bipinnate

Leaf and leaflet shapes[]

Being one of the more visible features, leaf shape is commonly used for plant identification. Similar terms are used for other plant parts, such as petals, tepals, and bracts.

Oddly pinnate, pinnatifid leaves (Coriandrum sativum, coriander or cilantro)
Partial chlorosis revealing palmate venation in simple leaves of Hibiscus mutabilis
Image Term Latin Refers principally to Description
Leaf morphology acicular.png acicular acicularis entire leaf Slender and pointed, needle-like.
Leaf morphology acuminate.png acuminate acuminatus leaf tip Tapering to a long point in a concave manner.
Leaf morphology Acute.png acute leaf tip or base Pointed, having a short sharp apex angled less than 90°.
Leaf morphology Apiculate.png apiculate apiculatus leaf tip Tapering and ending in a short, slender point.
Leaf morphology aristate.png aristate aristatus leaf tip Ending in a stiff, bristle-like point.
Leaf morphology Attenuate.png attenuate attenuatus leaf base Having leaf tissue taper down the petiole to a narrow base, always having some leaf material on each side of the petiole.
Leaf morphology base auriculate.png auriculate auriculatus leaf base Having ear-shaped appendages reaching beyond the attachment to the petiole or to the stem (in case of a seated leaf).
asymmetrical entire leaf With the blade shape different on each side of the midrib.
Leaf morphology Caudate.png caudate caudatus leaf tip Tailed at the apex.
cirrate leaf tip Having a rachis that extends beyond the leaf blade or leaflets into a long whip-like extension or cirrus (common in climbing palms). ecirrate: without a cirrus.
Leaf morphology cordate.png cordate, cordiform cordatus entire leaf Heart-shaped, with the petiole or stem attached to the notch.
Leaf morphology cuneate.png cuneate cuneatus leaf base Triangular, wedge-shaped, stem attaches to point.
Handdrawn Cuspidate.png cuspidate cuspidatus leaf tip With a sharp, elongated, rigid tip; tipped with a cusp.
Leaf morphology deltoid.png deltoid, deltate deltoideus entire leaf Shaped like Greek letter Delta, triangular, stem attaches to side.
Leaf morphology digitate.png digitate digitatus entire leaf With finger-like lobes, similar to palmate.[2]
Leaf morphology elliptic.png elliptic ellipticus entire leaf Oval, with a short or no point.
Leaf morphology ensiforme.PNG ensiform ensiformis entire leaf Shaped like a sword, long and narrow with a sharp pointed tip.
Leaf morphology apex emarginate.png emarginate emarginatus leaf tip Slightly indented at the tip.
Leaf morphology falcate.png falcate falcatus entire leaf Sickle-shaped.
Leaf morphology Fenestrate.png fenestrate fenestratus surface features Large openings through the leaf, see perforate. Sometimes use to describes leaf epidermal windows.
Plant morphology solid filiform.png filiform filiformis entire leaf Thread- or filament-shaped.
Leaf morphology flabelate.png flabellate flabellatus entire leaf Semi-circular, or fan-like.
Leaf morphology hastate.png hastate hastatus entire leaf Spear-shaped: Pointed, with barbs, shaped like a spear point, with flaring pointed lobes at the base.
Leaf morphology division laciniate.png laciniate lacinatus entire leaf Very deeply lobed, the lobes being very drawn out, often making the leaf look somewhat like a branch or a pitchfork.
laminar 3-d shape Flat (like most leaves)
Leaf morphology lanceolate.png lanceolate lanceolatus entire leaf Long, wider in the middle, shaped like a lance tip.
Leaf morphology linear.png linear linearis entire leaf Long and very narrow like a blade of grass.
Leaf morphology lobed.png lobed lobatus entire leaf Being divided by clefts, may be pinnately lobed or palmately lobed.
Leaf morphology Lorate.png lorate loratus entire leaf Having the form of a thong or strap.
Leaf morphology Lyrate.png lyrate lyratus entire leaf Shaped like a lyre, pinnately lobed leaf with an enlarged terminal lobe and smaller lateral lobes.
See also: List of lyrate plants
Leaf morphology Mucronate.png mucronate mucronatus leaf tip Ending abruptly in a small sharp point as a continuation of the midrib.[3]
Leaf morphology multifide.svg multifid multi + findere entire leaf Cleft into many parts or lobes.
Leaf morphology obcordate.png obcordate obcordatus entire leaf Heart-shaped, stem attaches at the tapering end.
Leaf morphology oblanceolate.png oblanceolate oblanceolatus entire leaf Much longer than wide and with the widest portion near the tip, reversed lanceolate.
Leaf morphology oblique.png oblique leaf base Asymmetrical leaf base, with one side lower than the other
Leaf morphology oblong.png oblong oblongus entire leaf Having an elongated form with slightly parallel sides, roughly rectangular.
Leaf morphology obovate.png obovate obovatus entire leaf Teardrop-shaped, stem attaches to the tapering end; reversed ovate.
obtrullate entire leaf Reversed trullate, the longer sides meet at the base rather than the apex.
Leaf morphology obtuse.png obtuse obtusus tip Blunt, forming an angle > 90°.
Leaf morphology orbicular.png orbicular orbicularis entire leaf Circular.
Leaf morphology ovale.png ovate ovatus entire leaf Oval, egg-shaped, with a tapering point and the widest portion near the petiole.
Leaf morphology palmate.png palmate palmatus entire leaf Palm-shaped, i.e., with lobes or leaflets stemming from the leaf base.[4]
Palmatilobé.svg palmately lobed palmatus entire leaf Lobes spread radially from a point. [5]
Palmatifide.svg palmatifid palma + findere entire leaf Palm-shaped, having lobes with incisions that extend less than half-way toward the petiole.
Palmatipartite.svg palmatipartite palma + partiri entire leaf Having palmate lobes with incisions that extend over half-way toward the petiole.
Palmatiséquée.svg palmatisect palma + secare entire leaf Having palmate lobes with incisions that extend almost up, but not quite to the petiole.
Leaf morphology pandurate.png pandurate panduratus entire leaf Fiddle-shaped; obovate with a constriction near the middle.
Leaf morphology pedate.png pedate pedatus entire leaf Palmate, with cleft lobes.[6]
Leaf morphology peltate.png peltate peltatus stem attachment A round leaf where the petiole attaches near the center. An example would be a lotus leaf.
Leaf morphology attachment connate-perfoliate.png perfoliate perfoliatus stem attachment With the leaf blade surrounding the stem such that the stem appears to pass through the leaf.
Leaf morphology Perforate.png perforate perforatus leaf surface features Many holes, or perforations on leaf surface. Compare with fenestrate.
Pennatilobé.svg pinnately lobed pinna + lobus entire leaf Having lobes pinnately arranged on the central axis.
Pennatifide.svg pinnatifid pinna + findere entire leaf Having lobes with incisions that extend less than half-way toward the midrib.
Pennatipartite2.svg pinnatipartite pinnatus + partiri entire leaf Having lobes with incisions that extend more than half-way toward the midrib.
Pennatiséquée.svg pinnatisect pinnatus + sectus entire leaf Having lobes with incisions that extend almost, or up to midrib.
Leaf morphology posture plicate.png plicate plicatus 3-d shape Folded into pleats, usually lengthwise, serving the function of stiffening a large leaf.
Leaf morphology reniform.png reniform reniformis entire leaf Shaped like a kidney: an oval with an inward curve on one side.
Leaf morphology apex retuse.png retuse leaf tip With a shallow notch in a round apex.
Leaf morphology rhomboid.png rhomboid, rhombic rhomboidalis entire leaf Diamond-shaped.
Leaf morphology apex rounded.png rounded rotundifolius leaf tip or base Circular, no distinct point.
semiterete 3-d shape Rounded on one side, but flat on the other.
Leaf morphology division sinuate.png sinuate sinuatus 3-d shape Circularly-lobed kind of leaves
Leaf morphology spear-shaped.png sagittate sagittatus entire leaf Arrowhead-shaped with the lower lobes folded, or curled downward
Leaf morphology spatulate.png spatulate spathulatus entire leaf Spoon-shaped; having a broad flat end which tapers to the base
Leaf morphology hastate.png spear-shaped hastatus entire leaf see hastate.
Leaf morphology subobtuse.png subobtuse subobtusus leaf tip or base Somewhat blunted, neither blunt nor sharp
Leaf morphology subulate.png subulate subulatus leaf tip Awl-shaped with a tapering point
Plant morphology solid terete.png terete 3-d shape Circular in cross-section; more or less cylindrical without grooves or ridges.
Leaf morphology trullate.png trullate entire leaf Shaped like a bricklayer's trowel
Leaf morphology truncate.png truncate truncatus leaf tip or base With a squared-off end
undulate undulatus 3-d shape Wave-like
Leaf morphology unifoliate.png unifoliate unifoliatus compound leaves With a single leaflet. It is distinct from a simple leaf by the presence of two and often by petiolules and stipels

Edge[]

Leaf margins (edges) are frequently used in visual plant identification because they are usually consistent within a species or group of species, and are an easy characteristic to observe. Edge and margin are interchangeable in the sense that they both refer to the outside perimeter of a leaf.

Image Term Latin adjective Description
Leaf morphology entire.png entire Forma
integra		 Even; with a smooth margin; without toothing
Leaf morphology ciliate.png ciliate ciliatus Fringed with hairs
Leaf morphology crenate.png crenate crenatus Wavy-toothed; dentate with rounded teeth
crenulate crenulate Finely crenate
crisped crispus curly
Leaf morphology dentate.png dentate dentatus Toothed. May be coarsely dentate, having large teeth, or glandular dentate, having teeth which bear glands
Leaf morphology denticulate.png denticulate denticulatus Finely toothed
Leaf morphology doubly serrate.png doubly serrate duplicato-dentatus Each tooth bearing smaller teeth
Leaf morphology serrate.png serrate serratus Saw-toothed; with asymmetrical teeth pointing forward
Leaf morphology serrulate.png serrulate serrulatus Finely serrate
Leaf morphology sinuate.png sinuate sinuosus With deep, wave-like indentations; coarsely crenate
Leaf morphology lobate.png lobate lobatus Indented, with the indentations not reaching the center
lobulate lobulatus With small lobes
Leaf morphology undulate.png undulate undulatus With a wavy edge, shallower than sinuate
Leaf morphology spiny.png spiny or pungent spiculatus With stiff, sharp points such as thistles

Leaf folding[]

Leaves may also be folded, sculpted or rolled in various ways. If the leaves are initially folded in the bud, but later unrolls it is called vernation, ptyxis is the folding of an individual leaf in a bud.

Image Term Latin Description
carinate or keeled carinatus with a longitudinal ridge
conduplicate folded upwards, with the surfaces close to parallel
Mimetes fimbrifolius (5211424654).jpg cucullate forming a hood, margins and tip curved downward
Involute vernation.jpg involute rolled upwards (towards the adaxial surface)
Palm leaf washingtonia robusta.jpg plicate plicatus with parallel folds
reduplicate folded downwards, with the surfaces close to parallel
Ledum groenlandicum.jpg revolute rolled downwards (towards the abaxial surface)
supervolute opposing left and right halves of lamina folded along longitudinal axis, with one half rolled completely within the other

Latin descriptions[]

The Latin word for 'leaf', folium, is neuter. In descriptions of a single leaf, the neuter singular ending of the adjective is used, e.g. folium lanceolatum 'lanceolate leaf', folium lineare 'linear leaf'. In descriptions of multiple leaves, the neuter plural is used, e.g. folia linearia 'linear leaves'. Descriptions commonly refer to the plant using the ablative singular or plural, e.g. foliis ovatis 'with ovate leaves'.[7]

See also[]

References[]

  1. ^ Radford, A. E., W. C. Dickison, J. R. Massey, C. R. Bell (1976), "Phytography - Morphological Evidence", Vascular Plant Systematics, Harper and Row, New YorkCS1 maint: uses authors parameter (link)
  2. ^ Also used to describe compound leaves with finger-like leaflets.
  3. ^ Mucronate, Answers.com, from Roget's Thesaurus.
  4. ^ "palmate (adj. palmately)". GardenWeb Glossary of Botanical Terms. Archived from the original on 2009-02-13. Retrieved 2008-10-19.
  5. ^ "Leaf description glossary". www.cs.rochester.edu. Retrieved 2017-11-02.
  6. ^ "Pedate leaf". Retrieved February 24, 2014.
  7. ^ Stearn (2004), pp. 439–440.

Bibliography[]

External links[]

Retrieved from ""