joint: (1) an articulation, as in a 1-foliolate leaf, Fig. 3 I; (2) a segment of some cladodes, as in many Cactaceae; (3) a node.
jugary: of glands, present on the rachises of bipinnate leaves at the junctions of pairs of pinnae or of pinnules, as in some Acacia species. Fig. 19 H. cf. interjugary.
juvenile leaves: the first-formed leaves, especially when they differ from the adult leaves.
karyotype: the gross morphology of the chromosome set, described in terms of number, length, etc.
keel: (1) a ridge like the keel of a boat, usually on the back of an organ; (2) the two fused anterior petals of the pea flower, see Fabaceae subfamily Faboideae.
kernel: the seed of a nut, drupe or pyrene.
kino: reddish exudate from the bark or wood of some trees, see ironbarks in Myrtaceae.
Kranz anatomy: a specialized anatomy associated with the C4 carboxylation pathway in plants. The vascular system is associated with at least two distinct photosynthetic cell types usually arranged in concentric layers. The cell types differ in ultrastructure and in function. Found in some grasses (Poaceae) and chenopods (Chenopodiaceae). See papers for explanation of terms. Refs Carolin, Jacobs, & Vesk (1973 & 1978).
labellum: the distinctive median petal in Orchidaceae, usually differing in size and shape from those either side.
labiate: lipped; where the limb of a corolla or a calyx is divided into 2 parts, called an upper and lower lip.
lacerate: as if torn; irregularly cut or cleft. Fig. 8 F.
laciniate: as if cut into narrow slender teeth or lobes. Fig. 8 G.
lacuna: a gap or cavity.
lamella: a thin plate-like layer. adj. lamellose.
lamina: an expanded portion of a leaf or petal. pl. laminas.
laminate: broadened into a lamina.
lanceolate: lance-shaped; 3-6 times as long as broad and broadest below the middle and tapering to the apex. Fig. 5 I.
lateral: attached to the side of an organ, e.g. leaves on a stem.
latex: a fluid exuded from cut surfaces of the leaves and stems of some plants, usually milky, sometimes yellowish and watery, e.g. as in many species in families Moraceae and Apocynaceae.
latrorse: turned sideways; of anthers, dehiscing longitudinally on the side. cf. extrorse, introrse.
lax: loose, not compact.
leaf: an organ borne on the stem of a plant, usually expanded and green; typically consisting of the more or less expanded lamina and the petiole or leaf stalk.
leaflet: one of the ultimate segments of a compound leaf. cf. pinna, pinnule.
leaf-opposed: arising from the stem opposite a leaf-base, as do some tendrils or inflorescences.
lectotype: a specimen selected from among those cited with the original description to serve in place of a holotype where the holotype is missing or destroyed, or where no holotype was designated.
legume: (1) a pod, a dry dehiscent fruit formed from one carpel and having two longitudinal lines of dehiscence, Fig. 18 I; (2) a member of the family Fabaceae.
lemma: the lower of two bracts enclosing the flower of a grass; male lemma - lemma enclosing a male flower; sterile lemma - an empty lemma.
lenticel: a small raised corky spot or line appearing on young bark, through which gaseous exchange occurs.
lenticular: a 3-dimensional shape like a doubly convex lens, circular in outline.
lepidote: covered with small, membranous scales.
leptomorph: applied to the rhizome system of some bamboos with indeterminate growth in which the aerial shoots arise laterally from an extensive rhizome system.
leptosporangiate: of ferns, having sporangia with walls consisting of a single layer of cells; the sporangium originating from a single cell. cf. eusporangiate.
liana (liane): a woody climbing plant.
lignified: converted into wood, hardened.
lignotuber: a woody swelling, partly or wholly underground, at the base of certain plants and containing numerous cortical buds, as in many eucalypts (Fig. 1 H); see mallee.
ligulate: (1) with a ligule; (2) of ray florets in Asteraceae, with a strap shaped limb.
ligule: (1) a variously shaped appendage facing towards the base of a leaf (especially in grasses), petiole, or perianth segment; (2) the strap shaped corolla lobe or limb in ray florets of Asteraceae.
limb: the expanded and usually flat portion of an organ, e.g. of a petal, or the expanding part of the corolla above a corolla tube.
linear: long and narrow with more or less parallel sides, more than 12 times as long as broad. Fig. 5 B.
linear-lanceolate: more than 12 times as long as broad and broadest in the lowest third and tapering to the apex.
linear-oblanceolate: more than 12 times as long as broad and broadest in the upper third and tapering to the base.
lineolate: marked with fine or obscure lines.
lithophyte: a plant growing on a rock, e.g. some orchids. cf. epiphyte
littoral: on or growing near the seashore.
loculicidal dehiscence: in capsules, dehiscence in median lines through the walls of the loculi rather than at the partitions between the loculi or at the placentas. Fig. 18 L. cf. septicidal.
loculus: a more or less closed cavity, containing the pollen in anthers (Fig. 20 C) and the ovules in an ovary (Fig. 13). pl. loculi.
lodicule(s): one or two scale-like structures below the stamens and ovary of a grass and regarded as a reduced perianth.
lomentum: a legume that breaks transversely into usually 1-seeded indehiscent articles when mature. Fig. 18 J. cf. schizocarp.
long-creeping: in ferns, a rhizome that elongates rapidly so that the fronds are usually well separated from each other. cf. short-creeping.
longitudinal: of venation, with several veins extending from the base to the apex of the lamina but the veins not more or less parallel with each other. Fig. 9 E.
lorate: of leaves, strap-shaped (moderately long with the two margins parallel).
lyrate: lyre-shaped, of pinnatifid or pinnatisect leaves with the terminal lobes much larger than the basal ones. Fig. 5 P.
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