plant morphology Phytomorphology is the study of the physical form and external structure of plants.Raven, P. H., R. F. Evert, & S. E. Eichhorn. ''Biology of Plants'', 7th ed., page 9. (New York: W. H. Freeman, 2005). . This is usually considered distinct from ...

, a cataphyll (sometimes also called a ''cataphyllum'' or cataphyll leafJackson, Benjamin, Daydon; A Glossary of Botanic Terms with their Derivation and Accent; Published by Gerald Duckworth & Co. London, 4th ed 1928) is a reduced, small

leaf A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

. Many plants have both "true leaves" (''euphylls''), which perform most of the

photosynthesis Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored i ...

, and cataphylls, which are modified to perform other functions. Cataphylls include bracts, bracteoles and bud scales, as well as any small leaves that resemble scales, known as scale leaves. The functions of cataphylls, such as bud scales, may be short-lived, and they are often shed after their function is fulfilled.

Etymology

Leaf bud of American Sweet gum (Liquidambar styraciflua) showing imbricate cataphylls 5405

Cataphyll comes from the

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...

, meaning "down", and , meaning "leaf".

Forms

In some cases, cataphylls perform a

transient ECHELON, originally a secret government code name, is a surveillance program ( signals intelligence/SIGINT collection and analysis network) operated by the five signatory states to the UKUSA Security Agreement:Given the 5 dialects that ...

function, after which they die and may shed. Those that shed early are said to be caducous. The

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined ...

s of '' Papaver'' species are shed during the very opening of the petals and are a dramatic example of caducous leaves. Cataphylls can have many other forms. Some, such as spines, corm-scales, and bud-scales, may be persistent but may not perform their major function until they die, whether or not they are physically shed. Examples of various kinds of living cataphylls include bulb-scales, rhizome-scales,

cotyledon A cotyledon (; ; ; , gen. (), ) is a significant part of the embryo within the seed of a plant, and is defined as "the embryonic leaf in seed-bearing plants, one or more of which are the first to appear from a germinating seed." The num ...

s, and scaly bracts. Several of these occur in various forms and contexts. For example, bud scales occur on numerous kinds of leaf or branch buds, as well as on flower buds. Protective masses of dead leaves encircle the stems of some species of palm trees or '' aloes'', but those are not usually regarded as cataphylls because their primary function while alive is photosynthesis. Acer pseudoplatanus cotyledons

Cotyledons as cataphylls

Cotyledon A cotyledon (; ; ; , gen. (), ) is a significant part of the embryo within the seed of a plant, and is defined as "the embryonic leaf in seed-bearing plants, one or more of which are the first to appear from a germinating seed." The num ...

s are widely regarded as a class of cataphyll, though many kinds of cotyledons function as living tissue and remain alive until, at least, the end of their function, at which time they wither and may drop off. They begin as leaf rudiments. Many kinds accumulate nutrient materials for storage, starting to give up their stored material as the plant germinates. Some, such as the

s of many

legume A legume () is a plant in the family Fabaceae (or Leguminosae), or the fruit or seed of such a plant. When used as a dry grain, the seed is also called a pulse. Legumes are grown agriculturally, primarily for human consumption, for livestock fo ...

s, conifers, and

cucurbits The Cucurbitaceae, also called cucurbits or the gourd family, are a plant family consisting of about 965 species in around 95 genera, of which the most important to humans are: *'' Cucurbita'' – squash, pumpkin, zucchini, some gourds *'' La ...

, develop chlorophyll and perform the first

for the germinating plant. Opuntia compressa - close-up (aka)

Corm scales

Like bulb-scales, corm scales are largely the basal parts of the photosynthetic leaves that show up above ground. Some species of cormous plants, such as some '' Lapeirousia,'' also produce cataphylls that act solely as tunic leaves for the corm. Unlike bulb-scales, however, the corm tunic has no significant storage function; that task is left to the Parenchyma of the cortex of the corm.

References

{{botany Plant morphology

Etymology

Forms

Cotyledons as cataphylls

Corm scales

See also

References