Glossary

This file is a glossary of the terms used in the Pteridophyta of Africa website. Click on a letter in the tabel below to take you to the first term whose name begins with that letter.

 

A B C D E F G H I L M N O P R S T U V W X


-

  • -fid
  • cleft into a number of parts, but not as deeply as -sect.
  • -foliolate
  • (of leaf) with leaflet(s).
  • -jugate
  • coupled or yoked together; applied to the leaflets of a pinnate leaf. E.g. 2-jugate: with 2 pairs of leaflets (i.e. 4 leaflets in all), sometimes also with a terminal leaflet in addition.
  • -lobed
  • possessing lobes.
  • -merous
  • a suffix indicating the number of parts possessed by an organ.
  • -nate
  • e.g. 2-nate (binate) in pairs; 5-nate, in fives etc.
  • -partite
  • deeply cleft into a number of divisions, e.g. 2-partite, with 2 divisions etc.
  • -sect
  • cleft into a number of parts, almost to the base or midrib.
  • -seriate
  • arranged in whorls, rows or series, e.g. 3-seriate, arranged in 3 series.

    2

  • 2-pinnate
  • a leaf in which the primary divisions are themselves pinnate; similarly 3-pinnate etc.

    A

  • abaxial
  • facing away from the axis (usually the lower side of a leaf surface).
  • abortion
  • the failure of a part to develop fully.
  • abortive
  • of or pertaining to abortion.
  • acaulescent
  • without a stem or stemless, although a stem-like peduncle is usually present.
  • accrescent
  • increasing in size with age .
  • acicular
  • very narrow, stiff and pointed, usually round in cross-section.
  • aculeate
  • armed with prickles (as opposed to spines).
  • acumen
  • a narrow point; sharp apex.
  • acuminate
  • gradually tapering to a sharp point with concave sides near the tip.
  • acute
  • with a tip that comes to a sharp point with ± straight-sided edges.
  • adaxial
  • facing towards the axis (usually the upper side of a leaf surface).
  • adherent
  • when two or more dissimilar organs touch but are not fused.
  • adnate
  • with unlike organs united.
  • adventitious
  • (of structures or organs) developing in an unusual position, e.g. of roots originating from a stem node.
  • alternate
  • arising singly at a node; this term includes spiral, as well as distichous arrangements.
  • alveoli
  • plural of alveolus.
  • alveolus
  • a small cavity.
  • amplexicaul
  • having a widened base which clasps the stem.
  • anastomosing
  • of veins joining up to form loops
  • annual
  • completing its life cycle from seed to seed in less than 12 months.
  • annular
  • arranged in a circle or in a ring; the shape of a ring.
  • anterior
  • in a position most remote from the axis.
  • anticous
  • on the anterior side or away from the axis.
  • antrorse
  • pointing forwards or upwards, or upwardly-directed.
  • apex
  • the tip or end point of a structure.
  • aphlebia
  • a pair of finely divided and much reduced pinnae at the base of the stipe.
  • apical
  • concerning or near the apex.
  • apiculum
  • a short sharp point.
  • appendage
  • a part added or attached to another, usually larger, structure.
  • appressed
  • pressed close against another organ. e.g. hairs, which lie flat against a leaf surface.
  • aquatic
  • living in water.
  • arachnoid
  • covered with long, delicate, cobweb-like hairs.
  • arcuate
  • curved, like a bow.
  • areole
  • a surface area well-defined by bounding veinlets, lines or cracks.
  • arista
  • a long very narrow bristle-like point.
  • aristate
  • bearing an arista.
  • armed
  • possessing spines, thorns or prickles.
  • article
  • an individual part or segment of an articulated object.
  • articulated
  • jointed or separating at a certain point, and leaving a clean scar.
  • articulation
  • the point at which an organ is articulated.
  • ascending
  • curving upwards, oblique at first then erect.
  • attenuate
  • tapering gradually to a slender point.
  • awn
  • a fine bristle, usually terminating an organ.
  • awned
  • possessing an awn.
  • axil
  • the angle between the axis and any organ which arises from it, e.g. the angle between a leaf and a branch.
  • axillary
  • arising from the axil.
  • axis
  • (in general) the main or central line of development of any plant or organ.

    B

  • barbate
  • bearded, having tufts of hairs.
  • barbed
  • with rigid points or lateral bristles pointing backwards.
  • barbellate
  • shortly or minutely barbed.
  • basiscopic
  • on the side (usually of a pinna) towards the base.
  • bi-
  • a prefix meaning two or twice.
  • biconvex
  • convex on both sides.
  • biserrate
  • serrate, with the teeth themselves serrate.
  • brachyblast
  • short, axillary, densely crowded branchlet.
  • bulbil
  • a small bulb or tuber arising in the axil of a leaf or in an inflorescence, on the aerial part of the plant.
  • bullate
  • (of lvs) surface prominently raised between the veins.

    C

  • caducous
  • falling unusually early.
  • caespitose
  • growing in tufts.
  • campanulate
  • bell-shaped, with a broad tube and a wide opening.
  • canaliculate
  • channelled or grooved.
  • canescent
  • covered with a grey pubescence or greyish colour.
  • capillary
  • hair-like, or very fine and slender.
  • capitate
  • like the head of a pin (as in the stigma of some flowers or in some gland-bearing hairs
  • castaneous
  • having the colour of a chestnut, i.e. dark brown
  • caudate
  • abruptly ending in a long tail-like tip or appendage.
  • caudex
  • a thickened, often woody, vertical or branched, perennial stem, usually subterranean or at ground level.
  • caulescent
  • possessing a stem or stems.
  • cauline
  • borne on or arising from the stem.
  • cespitose
  • alternative spelling of caespitose.
  • chartaceous
  • of a papery texture; thin and opaque.
  • cilia
  • plural of cilium.
  • ciliate
  • fringed with hairs.
  • ciliolate
  • minutely ciliate.
  • cilium
  • a hair on the margin of a structure.
  • circinnate
  • Inwardly coiled upon itself.
  • cladode
  • a green leaf-like structure formed by a modified stem.
  • clathrate
  • (applied to scales of e.g. a rhizome) with a latticed appearance owing to the cells having thickened lateral walls and transparent surface walls.
  • clavate
  • club-shaped, i.e. thickened towards the end.
  • climber
  • a plant which uses other plants or objects as a means of support but has its roots in the ground.
  • coherent
  • when two or more similar organs touch but are not fused.
  • columnar
  • shaped like a column.
  • compound
  • composed of several similar parts.
  • concolorous
  • with all parts of uniform colour, especially of the two surfaces of a leaf.
  • conduplicate
  • folded together lengthwise.
  • confluent
  • merging together, uniting.
  • connate
  • with like organs united.
  • connivent
  • of two or more organs with their bases separated but their apices touching one another.
  • convolute
  • rolled together, coiled
  • cordate
  • (of surface) heart-shaped; broadly ovate with a rounded notch at the base.
  • coriaceous
  • with a thick and firm texture, similar to leather.
  • corm
  • a short thick underground stem, which grows vertically, for example in many Iridaceae.
  • costa
  • the midrib of a pinna.
  • costae
  • plural of costa.
  • costapalmate
  • a basically palmate leaf in which the petiole extends into the lamina as a well-defined axis, dividing the lamina in two.
  • costule
  • the midrib of a pinnule or pinna segment.
  • crenate
  • (of margin) with crenations.
  • crenation
  • a blunt or rounded tooth, often wider than long.
  • crenulate
  • minutely crenate.
  • crispate
  • (of hairs) closely and stiffly curled.
  • crustaceous
  • hard, thin and brittle.
  • cultivar
  • a cultivated variety.
  • cuneate
  • wedge-shaped, the narrow end below.
  • cupule
  • a cup-shaped organ.
  • cusp
  • an elongated, sharp, rigid point.
  • cuspidate
  • with the tip abruptly narrowed to a sharp, rigid point.

    D

  • deciduous
    1. of lvs: falling off at the end of the growing season every year;
    2. of other organs: falling before the majority of adjacent or associated organs.
  • decumbent
  • (of stems) lying on the ground and tending to rise at the end.
  • decurrent
  • having the base prolonged down the axis. Usually applied to leaves where the lamina is continued downwards as a wing on the petiole or stem.
  • decussate
  • opposite leaves in 4 rows up and down the stem, in pairs alternating at right-angles.
  • dehiscence
  • the method or process of opening of a seed-pod or anther; loculicidal, when the split opens into a cavity or loculus, septicidal when the split occurs at a septum or partition and circumscissile when the object splits transversely, the upper part coming off as a lid.
  • dehiscent
  • splitting open, when ripe or mature.
  • dendritic
  • (of hairs) much branched like the crown of a tree.
  • dentate
  • with a toothed margin, the teeth pointing outwards not forwards.
  • denticulate
  • minutely dentate.
  • depressed
  • flattened from above.
  • determinate
  • having a definite end point; e.g. as in an inflorescence in which the main axis ends in a flower and cannot extend further.
  • dichotomous
  • (of branching) forking regularly into two.
  • diffuse
  • of branching that is open or loosely spreading.
  • digitate
  • (of leaflets) a compound leaf in which the leaflets arise from the same central point. For this work, we have chosen digitate to mean leaves which are truly compound (i.e. composed of separate leaflets) and palmate leaves to be simple leaves where the radiating fingers are joined together near the base.
  • dilated
  • widened, flattened, expanded or enlarged.
  • dimidiate
  • (of pinnae or pinnules) in which the midrib forms the basiscopic margin for a significant distance.
  • dimorphic
  • having two forms.
  • disarticulating
  • breaking apart at the joints.
  • discolorous
  • of two colours, especially of a leaf where the two surfaces are of a different colour.
  • distal
  • the part or end farthest away from the base or point of attachment.
  • distichous
  • 2-ranked, with (e.g.) leaves on opposite sides of a stem and in the same plane.
  • divaricate
  • spreading apart widely.
  • divergent
  • spreading apart but not as widely as divaricate.
  • domatia
  • Plural of domatium.
  • domatium
  • a small tuft of hair; a cavity or pocket formed by a plant which is usually inhabited by insects, particularly ants or mites. Domatia are usually found in the axils of the lateral veins where they meet the main vein on the underside of the leaf and there is often a corresponding raised dome on the upper surface of the leaf.
  • dorsiventral
  • with a distinct upper and lower side, two-sided, not terete.
  • dorsiventrally flattened
  • flattened in the plane of the back and front and not of the sides.

    E

  • echinate
  • covered with short spines or prickles.
  • eglandular
  • without glands.
  • ellipsoid
  • a solid object, elliptic in longitudinal section.
  • ellipsoidal
  • having the shape of an ellipsoid.
  • elliptic
  • having the shape of an ellipse, broadest at the middle and narrower at the two equal ends.
  • elongate
  • lengthened, extended.
  • emarginate
  • with a notch at the apex.
  • embryo
  • the initial stage in the development of the plant while still enclosed within the seed.
  • emergent
  • growing in water, but with some parts of the plant raised above the surface.
  • endemic
  • confined to a region or country and not native anywhere else.
  • entire
  • with an even and continuous margin without lobes, teeth or other indentations.
  • epi-
  • a prefix meaning on, upon or attached to.
  • epidermis
  • the primary outermost layer of cells of all plant organs.
  • epiphyte
  • a plant which grows on another plant but without deriving any nourishment from it. Most often applied to orchids which grow on trees as opposed to being terrestrial.
  • epiphytic
  • of or pertaining to an epiphyte.
  • equitant
  • folded lengthwise so that the base of each leaf enfolds the next.
  • erect
  • growing vertically.
  • erecto-patent
  • between erect and patent.
  • erose
  • (of margin) irregularly toothed, as if gnawed.
  • evergreen
  • retaining green leaves throughout the dormant season.
  • excentric
  • to one side; off centre.
  • excurrent
  • going out beyond the margin of an organ (as in the vein of a leaf going beyond the margin).
  • exserted
  • projecting beyond, protruding.
  • extra-axillary
  • beyond or outside the axil.

    F

  • falcate
  • curved like a scythe or sickle.
  • family
  • a unit of classification above the level of genus and tribe but below that of order.
  • farinose
  • covered with a meal-like powder.
  • fascicle
  • a tight bundle or cluster.
  • fasciculate
  • arranged in fascicles.
  • fastigiate
  • strictly erect and parallel to other organs, e.g. with reference to stems or branches.
  • ferrugineous
  • rust-coloured or reddish-brown.
  • fertile
  • producing viable seeds or pollen.
  • fibrous
  • composed of, or like, fibres.
  • fimbriate
  • with the margin divided into a fringe of slender lobes (fimbriae).
  • flabellate
  • fan-shaped or broadly wedge-shaped.
  • flange
  • a winged or ribbed projection.
  • flexuous
  • having a more or less zigzag or wavy form.
  • floccose
  • clothed with woolly hairs, which are disposed in tufts or tend to rub off and adhere in small masses.
  • foliaceous
  • having the appearance or nature of a leaf.
  • foliage leaves
  • ordinary leaves, as opposed to those which have undergone metamorphoses as bracts, petals etc.
  • foveolate
  • marked with small pits or depressions on the surface.
  • free
  • not joined or united.
  • fulvous
  • tawny, brownish-yellow or orange.
  • funnel-shaped
  • shaped like a funnel or cone, gradually widening.
  • furcate
  • forked.
  • fuscous
  • greyish-brown or dark greyish-brown.
  • fusiform
  • (of solid object) spindle-shaped, i.e. thick in the middle and tapering towards each end.

    G

  • gamete
  • the sex cell or nucleus which combines with another gamete to form the fertilised egg.
  • gametophyte
  • a plant which produces gametes.
  • genera
  • geniculate
  • bent abruptly like a knee.
  • genus
  • a unit of classification above the rank of species but below the rank of family; a collection of genetically related species.
  • geophyte
  • a plant with perennating buds located on the plant below the soil.
  • gibbous
  • bulging or swollen on one side.
  • glabrescent
  • becoming glabrous with increasing age or maturity.
  • glabrous
  • without hairs.
  • gland
  • a protuberance or depression which secretes a fluid which is often sticky; if stalked, known as a glandular hair.
  • glandular
  • furnished with glands.
  • glaucous
  • pale bluish-green or with a pale bloom.
  • glochid
  • a very small spine or bristle, barbed at the tip.
  • glutinous
  • with a sticky exudate.
  • granulate
  • finely covered with very small granules.

    H

  • hastate
  • when the base of a leaf has two ± triangular lobes which diverge away from the midvein.
  • hemiparasite
  • a plant which can parasitise another plant but is also capable of growing by itself.
  • hemiparasitic
  • of or pertaining to a hemiparasite.
  • herb
  • any vascular plant which is not woody.
  • herbaceous
  • possessing the characteristics of a herb.
  • heteromorphic
  • of different forms.
  • heterosporous
  • producing spores of 2 sizes.
  • hirsute
  • covered with long, moderately stiff and not interwoven hairs.
  • hirtellous
  • minutely hirsute.
  • hispid
  • rough with stiff hairs.
  • hispidulous
  • minutely hispid.
  • hyaline
  • delicate, translucent or transparent tissue.

    I

  • imbricate
  • overlapping like tiles
  • immersed
  • completely submerged or surrounded.
  • imparipinnate
  • a pinnate leaf with an odd number of leaflets, which has a single leaflet at the end of the leaf rhachis.
  • incised
  • cut; slashed irregularly, ± deeply and sharply; an intermediate condition between toothed and lobed.
  • included
  • not projecting beyond; not protruding.
  • incurved
  • curved inwards.
  • indefinite
  • numerous and often variable in number.
  • indehiscent
  • not splitting open when ripe or mature.
  • indeterminate
  • having no definite end point e.g. as in an inflorescence which can continue growing along the main axis and does not terminate in a flower.
  • indumentum
  • any covering, such as hairs, wool, scales etc.
  • indurated
  • hardened and toughened.
  • indusial
  • of or pertaining to an indusium.
  • indusium
  • a piece of tissue ± covering or enclosing a sporangium or group of sporangia.
  • inflexed
  • bent inward, turned abruptly inward.
  • inserted
  • attached to, borne upon or growing from.
  • internode
  • the portion of a stem between successive nodes.
  • interrupted
  • not continuous.
  • introduced (species)
  • introduced to a region deliberately or accidentally by man.
  • involute
  • inrolled; with the edges of the leaves rolled inwards by both margins so as to expose the abaxial surface.

    L

  • lacerate
  • torn; irregularly cleft or cut.
  • lacinia
  • a slender lobe.
  • laciniae
  • plural of lacinia.
  • laciniate
  • deeply and irregularly divided into slender lobes.
  • lacunar
  • with empty air space or gap within a tissue.
  • lamella
  • a thin plate or layer.
  • lamellae
  • plural of lamella.
  • lamelliform
  • having the form of a lamella.
  • lamina
  • the flattened and expanded part of a leaf or petal.
  • lanate
  • covered with soft, flexuous, intertwined hairs.
  • lanceolate
  • a plane shape which is narrowly egg-shaped in outline with the broadest part near the base.
  • lateral
  • on the side or along the margin.
  • lax
  • loose, not dense.
  • leaf
  • an organ originating from and attached to a stem, usually with a short stalk attached to a flat lamina.
  • leaflet
  • a leaf-like part of a compound leaf.
  • lepidote
  • clothed with scales.
  • ligulate
  • with the shape of a tongue or strap; possessing a ligule.
  • ligule
    1. (in Poaceae) a thin membranous or rim-like structure found at the top of the leaf sheath;
    2. the strap-shaped corolla found in the florets of certain Asteraceae;
    3. (in some Pteridophyta) a small flap of tissue on the adaxial side of the leaf.
  • linear
  • long and narrow, the sides parallel or nearly so.
  • lithophyte
  • a plant growing on rocks.
  • lithophytic
  • of or pertaining to a lithophyte.
  • lobe
  • any division of an organ not completely separated from the next.
  • longitudinal
  • lengthways.
  • lorate
  • strap-shaped.
  • lyrate
  • a pinnatifid leaf with a large terminal lobe and smaller lateral lobes.

    M

  • mamillate
  • with small nipple-shaped projections
  • mangrove
  • woody plants growing in muddy swamps which are inundated by tides.
  • medifixed
  • (of hairs) attached by the middle with the two branches pointing in opposite directions and often lying appressed to the surface.
  • membranous
  • of a thin texture and translucent.
  • midrib
  • the principal, usually central, vein of a leaf or other organ.
  • miombo woodland
  • woodland type dominated by trees of the species of Brachystegia, Julbernardia or Isoberlinia; an important vegetation type in south-central Africa.
  • monomorphic
  • having only 1 form.
  • monopodial
  • (of branching) where the main axis remains dominant so that all secondary shoots are clearly lateral.
  • monotypic
  • having only one representative; used especially of a genus with only one species.
  • mucro
  • a short narrow point, projecting from the apex.
  • mucronate
  • provided with a mucro.
  • mucronulate
  • minutely mucronate.
  • muricate
  • rough, with sharp tubercles or protuberances.
  • muticous
  • blunt and without a point.

    N

  • native
  • a plant which arose or became present in a region by natural means.
  • naturalised
  • an introduced plant which has become self-perpetuating in the flora area.
  • nerve
  • the principal or more conspicuous veins or ribs of a leaf, sepal or petal.
  • node
  • the place on a stem at which a leaf or other organs arise.
  • nodose
  • having nodes, knots or swellings.

    O

  • ob-
  • a prefix meaning "opposite", "inverse" or "against". When used as a prefix before a word describing the shape of an organ, it means that the organ is attached to its stalk at the opposite end to the usual case.
  • obcordate
  • a cordate leaf, but attached at the unlobed end, so that the apex is notched.
  • oblanceolate
  • the inverse of lanceolate.
  • oblate
  • transversely broadly elliptic.
  • oblique
    1. slanting;
    2. (of leaf) not symmetrical about the midrib at the base of the leaf.
  • oblong
  • a plane shape almost rectangular in outline but with rounded ends.
  • obovate
  • the inverse of ovate.
  • obovoid
  • the inverse of ovoid.
  • obsolete
  • not evident or apparent; rudimentary.
  • obtuse
  • a blunt or rounded end, the margins forming an angle greater than 50°.
  • operculate
  • of or pertaining to an operculum.
  • operculum
  • a lid or cover which comes off by a transverse line of dehiscence.
  • opposite
    1. of leaves or branches when two are borne at the same node on opposite sides of the stem;
    2. of other organs (e.g. stamens) when opposite or placed in front of the petals instead of alternating with them.
  • ostiole
  • an opening or pore.
  • ovate
  • (of a plane shape) egg-shaped in outline with the broadest part near the base.
  • ovoid
  • (of a solid shape), ovate in outline, with a circular transverse section.

    P

  • pallid
  • pale in colour.
  • palmate
  • (of a leaf) a leaf which is not truly compound in which the lobes are arranged like the fingers of a hand.
  • palmatifid
  • the palmate equivalent of pinnatifid.
  • palmatilobed
  • the palmate equivalent of pinnatilobed.
  • palmatipartite
  • the palmate equivalent of pinnatipartite.
  • palmatisect
  • the palmate equivalent of pinnatisect.
  • pandurate
  • fiddle-shaped.
  • papilla
  • a minute nipple-like protuberance.
  • papillae
  • plural of papilla.
  • papillose
  • covered with papillae.
  • paraphyses
  • sterile hairs, sometimes clavate or with an enlarged apical cell, occurring among sporangia in a sorus.
  • parasite
  • a plant which derives its food wholly or partially (hemiparasite) from other living plants to which it is directly attached.
  • parasitic
  • of or pertaining to a parasite.
  • paripinnate
  • a pinnate leaf with an even number of leaflets and no single leaflet at the end.
  • patelliform
  • shaped like a small dish, circular and with a rim.
  • patent
  • spreading ± at right-angles.
  • pectinate
  • divided at the edge to form many parallel parts like the teeth of a comb.
  • pedate
  • used for leaves which are palmately divided, with the lateral lobes again partially divided.
  • pellucid
  • translucent.
  • peltate
  • an organ, the stalk of which is attached to a flat surface and not the margin; the attachment is not necessarily central.
  • pendulous
  • hanging down or drooping.
  • penicillate
  • with a coma shaped ± like a pencil or brush.
  • perennial
  • living for 3 or more growing seasons.
  • persistent
  • remaining attached, not falling off.
  • petiolate
  • possessing a petiole.
  • petiole
  • the stalk of a leaf.
  • petiolulate
  • possessing a petiolule.
  • petiolule
  • the stalk of a leaflet.
  • phloem
  • the part of the vascular system made up of living cells that function primarily in the conduction of food; the inner bark.
  • phyllode
  • a green flattened petiole resembling a leaf.
  • pilose
  • with long soft hairs.
  • pinna
  • the primary division of a pinnately compound leaf.
  • pinnae
  • plural of pinna.
  • pinnate
  • a leaf composed of more than 3 leaflets arranged in two rows along a common stalk or rhachis.
  • pinnatifid
  • with the margin divided more than halfway to the midvein or centre and forming pinnately arranged lobes.
  • pinnatilobed
  • with the margin divided to about half the distance to the midvein or centre and forming pinnate lobes.
  • pinnatipartite
  • with the leaf divided almost to the midvein or centre and forming pinnate lobes.
  • pinnatisect
  • with the leaf divided to the midvein or centre and forming pinnate lobes.
  • pinnule
  • the primary segment of a pinna.
  • plano-convex
  • convex on one side and flat on the other.
  • plicate
  • longitudinally folded or pleated.
  • polymorphic
  • occurring in many forms.
  • pore
  • a small opening.
  • posterior
  • in position nearest to the axis.
  • posticous
  • on the posterior side, next to the axis.
  • prickle
  • a small sharp outgrowth from the bark or surface.
  • process
  • a projection or projecting part.
  • procumbent
  • with stems lying along the ground.
  • proliferous
  • bearing adventitious buds (q.v.) on the leaves or in the flowers, capable of rooting and forming separate plants.
  • prophyll
  • a much reduced leaf or bract.
  • prostrate
  • lying closely along the surface of the ground.
  • prothallus
  • a small, usually flat, plant body not clearly differentiated into stems and leaves, formed by the germination of a spore.
  • proximal
  • the part or end nearest to the base or point of attachment.
  • pruinose
  • covered with a whitish wax or very fine powder.
  • pseudo-
  • a prefix meaning false.
  • puberulent
  • minutely pubescent.
  • pubescent
  • with soft short hairs.
  • pulvinate
  • of or pertaining to a pulvinus.
  • pulvinus
  • a swelling, shaped like a cushion or pad, round or flattened, usually occurring at the base of the leaf or petiole.
  • punctate
  • dotted or shallowly pitted, often with glands.
  • pungent
  • ending in a sharp rigid point.
  • pyriform
  • pear-shaped.
  • pyrophyte
  • a plant able to tolerate fire or needing fire to stimulate flowering.
  • pyrophytic
  • of or pertaining to a pyrophyte.

    R

  • radical
  • (of leaves) arising from the base of a stem or from a rhizome.
  • radicle
  • the embryonic root; the part of the developing embryo that will produce the root.
  • recurved
  • curved backwards.
  • reflexed
  • bent backwards or downwards.
  • reniform
  • kidney-shaped, i.e. with a notch at the base and rounded at the apex.
  • repand
  • when the margin is slightly uneven or wavy by turning inwards and outwards but to a lesser extent than sinuate.
  • reticulation
  • a network or net-like arrangement of veins or fibres.
  • retrorse
  • pointing backwards or downwards; backwardly-directed.
  • revolute
  • with margins rolled outwards towards the abaxial side.
  • rhachides
  • plural of rhachis.
  • rhachis
    1. the principal axis of an inflorescence above the peduncle;
    2. the axis on which the leaflets of a compound leaf are inserted.
  • rhizomatous
  • possessing a rhizome.
  • rhizome
  • a horizontal stem, on or under the ground, lasting more than one growing season.
  • rhombic
  • diamond-shaped.
  • rosette
  • leaves crowded together on account of the very short internodes.
  • rosulate
  • in a rosette.
  • rotund
  • a leaf shape intermediate between broadly elliptic and circular.
  • ruderal
  • growing amongst rubbish or rubble; of waste or weedy places.
  • rudimentary
  • incompletely developed.
  • rufous
  • rusty or reddish-brown.
  • rugose
  • with wrinkles or grooves in the surface.
  • rugulose
  • minutely rugose.
  • runcinate
  • with teeth pointing backwards towards the base.

    S

  • saccate
  • forming a small sac or bag.
  • sagittate
  • arrow-shaped; the base has two acute lobes which point backwards to the base of the petiole.
  • salver-shaped
  • with a narrow tube opening suddenly into a wide cup-shaped mouth.
  • saprophyte
  • a plant which derives its food wholly or partially (partial saprophyte) from dead organic matter. According to this page, there are no saprophytic flowering plants; species normally referred to as saprophytic are myco-heterotrophic.
  • sarmentose
  • with long slender stolons or whip-like branches.
  • scaberulous
  • minutely rough.
  • scabrid
  • rough to the touch, usually because of the presence of very short harsh hairs.
  • scandent
  • climbing.
  • scarious
  • membranous, thin and dry, not green.
  • scorpioid
  • coiled like a scorpion's tail (in one plane).
  • scrub
  • a community dominated by shrubs.
  • secund
  • all directed to one side.
  • seed
  • a reproductive unit formed from the fertilised ovule.
  • semi-
  • a prefix meaning partially.
  • semi-amplexicaul
  • partially amplexicaul.
  • sensu
  • in the sense of.
  • septa
  • plural of septum.
  • septifragal
  • the form of dehiscence in which the septa are separated from the valves.
  • septum
  • a partition or cross-wall.
  • sericeous
  • with silky appressed hairs.
  • serrate
  • with a toothed margin, the teeth more or less regular and pointing forwards.
  • serrulate
  • minutely serrate.
  • sessile
  • without a stalk.
  • seta
  • a bristle or stiff hair.
  • setaceous
  • shaped like a bristle.
  • setae
  • plural of seta.
  • setose
  • covered with stout rigid bristles.
  • setulose
  • minutely setose.
  • sheath
  • a tube-like structure sometimes split longitudinally for part or whole of the length with the two margins overlapping, that encloses an organ either completely or partially, e.g. a leaf-sheath of Poaceae.
  • shrub
  • a woody plant, typically with several main stems, that at maturity does not attain tree height (5 m).
  • shrublet
  • a small shrub.
  • simple
    1. unbranched;
    2. (of a hair) unbranched, with or without a terminal gland;
    3. (of a leaf) not separated into leaflets, although the leaf lamina may be deeply lobed.
  • sinuate
  • when the margin is uneven or wavy by turning inwards and outwards but not deeply enough to be lobed (i.e. in and out, not up and down).
  • sinus
  • the depression between 2 lobes or teeth.
  • smooth
  • used in the sense of 'not rough' (sometimes elsewhere used to mean glabrous).
  • soral
  • of or pertaining to a sorus.
  • sordid
  • of a dull, dirty or muddy colour.
  • sori
  • plural of sorus.
  • sorus
  • a group of sporangia.
  • spathulate
  • spoon-shaped.
  • species
  • the basic unit in a taxonomic classification denoting a group of organisms that appear more similar to each other than to any other group and are usually assumed to be able to interbreed and produce fully fertile progeny.
  • species
  • plural of species.
  • spine
  • a hard sharp-pointed structure, often long and narrow.
  • sporangia
  • plural of sporangium.
  • sporangium
  • a structure containing spores.
  • spore
  • a small asexual reproductive body, usually unicellular, and always without tissue differentiation.
  • sporocarp
  • an organ enclosing the sorus or sori in heterosporous ferns, hardened in Marsilea, membranous in Azolla and Salvinia.
  • sporophyll
  • a leaf bearing or subtending sporangia.
  • sporophyte
  • a plant which produces spores.
  • squarrose
  • spreading or recurved at some point above the base.
  • stellate
  • star-shaped; often applied to stellate hairs which have several branches radiating from a central point.
  • stem
  • the main axis of the plant or a branch of the main axis which (at first) produces leaves at the nodes.
  • sterile
  • not producing viable seeds or pollen.
  • stilt root
  • a supporting root which arises from lower nodes above the ground, usually on weak or tall grasses which require extra support.
  • stipe
    1. the stalk supporting a carpel or gynoecium;
    2. (in ferns) the stalk of the frond.
  • stipel
  • a structure similar to a stipule but occurring at the base of the leaflets of a compound leaf.
  • stipellae
  • plural of stipel.
  • stipellate
  • of or pertaining to a stipel.
  • stipitate
  • supported on a stipe.
  • stipular
  • of or pertaining to a stipule.
  • stipulate
  • possessing stipules.
  • stipule
  • a scale-like or leaf-like appendage usually at the base of the petiole.
  • stolon
    1. a short-lived, horizontal stem, either above, on or below the surface of the ground, rooting at one or more nodes;
    2. (in the Cyperaceae) long and slender scale-covered subterranean rhizomes ending in buds which give rise to new plants.
  • striate
  • bearing striations.
  • striation
  • fine, parallel, longitudinal lines, grooves or ridges.
  • strigose
  • with stiff appressed straight hairs.
  • strigulose
  • minutely strigose.
  • strobilate
  • of or pertaining to a strobilus.
  • strobili
  • plural of strobilus.
  • strobilus
  • a fir-cone, or an inflorescence or fruit that resembles one by having large and imbricated scales.
  • style
  • that part of the female part of the flower connecting the stigma to the ovary.
  • stylopodium
  • a disk-like enlargement at the base of the style.
  • sub-
  • a prefix meaning "slightly, "somewhat", "almost" or "below".
  • subglabrous
  • very slightly, but persistently, hairy.
  • submarginal
  • almost marginal; positioned very close to the margin.
  • subopposite
  • almost but not quite opposite.
  • subshrub
  • a plant with a woody base to the stems but with upper part of the stems herbaceous.
  • subshrubby
  • having the characteristics of a subshrub.
  • subspecies
  • a unit of classification below the rank of species and above the rank of variety, often used for grouping geographical variants of a species.
  • subtend
  • to extend under, or be opposite to, another structure.
  • subulate
  • flat and narrow, tapering from the base to a sharp tip.
  • succulent
  • fleshy and juicy, thick and soft within.
  • sulcate
  • grooved or furrowed.
  • superficial
  • on the surface.
  • supra-axillary
  • arising above an axil.
  • suture
  • the line along which two parts have been united or the line along which a structure splits open.
  • sympodial
  • (of branching) where the terminal bud ceases to grow (or its function and position are taken another structure such as a flower) and growth is continued by a lateral bud or branch.

    T

  • taxa
  • plural of taxon.
  • taxon
  • a taxonomic entity of any rank.
  • terete
  • circular or oval in cross-section, without grooves or ridges.
  • terminal
  • borne at the end of a stem and limiting its growth.
  • terrestrial
  • on or in the ground.
  • tessellate
  • having a chequered pattern.
  • tetrad
  • a group of 4 pollen grains or spores.
  • tetragonous
  • four-angled.
  • thalli
  • plural of thallus.
  • thallus
  • a vegetative body not differentiated into stems and leaves.
  • tomentellous
  • slightly tomentose.
  • tomentose
  • with a tomentum.
  • tomentum
  • a dense felty mass of matted or tangled hairs.
  • transverse
  • crosswise.
  • tree
  • a woody plant, typically with one main trunk, that at maturity reaches at least 5 m.
  • triangular
  • having ± the shape of a triangle.
  • tribe
  • a unit of classification above the level of genus and below that of family.
  • trigonous
  • of a solid body, triangular in section but obtusely angled.
  • trilete
  • (e.g. of spores) having three scar lines forming a Y, or basically tetrahedral.
  • trimorphic
  • having three forms.
  • triquetrous
  • of a solid body, triangular in section and acutely angled.
  • truncate
  • with the base or apex at right angles to the midvein as if cut across at the bottom or top.
  • tuber
  • a swollen portion of a stolon or rhizome.
  • tubercle
  • a swelling, knob or thickened protuberance on a surface, sometimes found at the base of a hair.
  • tuberculate
  • covered with tubercles.
  • tuberous
  • resembling a tuber or producing tubers.
  • tuft
  • a loose, compact or dense cluster of vegetative shoots and/or stems.
  • tufted
  • in the form of a tuft.
  • twining
  • climbing by winding the stem around the support.

    U

  • unarmed
  • devoid of thorns, spines or prickles.
  • uncinate
  • with a hook at the end.
  • undulate
  • wavy in a plane at right angles to the surface (i.e. up and down not in and out).
  • unguiculate
  • contracted at base into a claw.
  • urceolate
  • shaped like a water pot or urn, with a rounded base and short broad tube that is narrowed above and slightly expanded at the very top.
  • utricle
  • a flask-like or bottle-shaped object enclosing a female flower in the genus Carex.

    V

  • variety
  • a unit of classification below the level of species; varieties are separated on the basis of form and colour but the varieties are usually not geographically separated and individuals of different varieties can freely interbreed.
  • vascular bundle
  • a strand or unit of phloem or xylem, with or without a surrounding sheath, which carries water and nutrients.
  • vascular plants
  • species of plants which belong to the two major divisions, Pteridophyta and Spermatophyta.
  • vein
  • a small strand of vascular tissue.
  • velutinous
  • with a dense indumentum of fine, soft, straight hairs; velvety.
  • venation
  • the arrangement of the veins in a leaf.
  • verrucose
  • covered with rough wart-like projections.
  • vesicle
  • a sac, bladder or cavity, usually small and filled with gas or fluid.
  • vestigial
  • a trace or mark left by a structure no longer developed but present in ancestral forms.
  • villous
  • covered with long, soft, weak hairs.
  • virgate
  • long slender and straight; wand-like.
  • vlei
  • seasonally moist or wet, sloping, shallow, grass-covered depression.

    W

  • whorl
  • more than 2 organs of the same kind arising at the same level.
  • wing
    1. (in general) any flat expansion of an organ;
    2. each of the two lateral petals in the flowers of the Papilionoideae;
    3. each of the two inner, usually petaloid, sepals in the flowers of the Polygalaceae.
  • winged
  • possessing a wing.

    X

  • xerophytic
  • adapted to a dry climate or habitat.
  • xylem
  • the principal cells of the wood; important in water movement.