microphyll
Quick Summary
A microphyll is a type of leaf characterized by a single, unbranched vein and the absence of a demonstrable gap around the leaf trace. This term can also refer to any small leaf. Plants with microphylls are described as microphyllous. This type of leaf structure is found in certain plant groups, such as lycophytes, which were among the earliest vascular plants to develop differentiated shoot systems. In contrast to megaphylls, which are larger leaves formed from the webbing of branching axes, microphylls evolved from simpler emergences on the plant's axes.123
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lower vascular plantLeaves…scalelike, needlelike, or awl-shaped “microphylls” with a single, unbranched vein. The sphenophytes have “sphenophylls”—scalelike leaves with a single vein in the modern Equisetum or wedge-shaped leaves with a dichotomously forking vein system in many of the fossil forms. These leaf forms are all so simple that the vascular connection…
Read More…scalelike, needlelike, or awl-shaped “microphylls” with a single, unbranched vein. The sphenophytes have “sphenophylls”—scalelike leaves with a single vein in the modern Equisetum or wedge-shaped leaves with a dichotomously forking vein system in many of the fossil forms. These leaf forms are all so simple that the vascular connection…
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lycophyteGeneral featuresGenerally, each leaf, or microphyll, is narrow and has an unbranched midvein, in contrast to the leaves of the ferns and seed plants, which generally have branched venation. The sporangia (spore cases) occur singly on the adaxial side (the upper side facing the stem) of the leaf. The lycophytes…
Read MoreGenerally, each leaf, or microphyll, is narrow and has an unbranched midvein, in contrast to the leaves of the ferns and seed plants, which generally have branched venation. The sporangia (spore cases) occur singly on the adaxial side (the upper side facing the stem) of the leaf. The lycophytes…
Read More