The Cycad Society, Inc. - Illustrated Glossary of Cycad Terms (original) (raw)

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Illustrated Glossary of Cycad Terms

Compiled by Jody L. Haynes

. INTRODUCTION

Students and growers of cycads will routinely encounter terms that have specific meanings in the context of various scientific subdisciplines�such as biology, ecology, taxonomy, or horticulture. While some such terms are to be expected only in formal botanical descriptions (e.g. arcuate, chartaceous, epigeous), a few are actually exclusive to cycads (e.g. omnule, omnel, corruptule, corruptel), and still others are commonly used incorrectly in reference to cycads (_e.g._bulb, endosperm, frond). The following compilation is based on the �Glossary of Terms Encountered in Cycad Systematics� provided as Appendix 2 in the well-known book, Cycad Classification: Concepts and Recommendations (Walters & Osborne, 2004). While this was a useful resource, it was specific to taxonomy and systematics and it was somewhat incomplete. We have developed a new �Expanded Glossary of Cycad Terms� designed to be a comprehensive, ever-evolving, and dynamic resource for individuals interested in cycads and their study and cultivation. The �expanded glossary� includes more than 1,200 terms, and it will be modified as needed. This illustrated glossary provides cycad-specific examples for more than 500 of these terms.

GLOSSARY

The following terms (or the Greek or Latin roots or equivalents) may be encountered in cycad biology, ecology, ethnobotany, evolution, genetics, taxonomy, nomenclature, systematics, and/or cultivation. Each term below is illustrated with a cycad-specific example; clicking on the underlined terms will display their respective illustrations.

The following notes will provide additional useful information for users of this illustrated glossary:

1. Items in boldface within a definition are defined elsewhere in the list.

2. While Cf. literally means �to compare�, in most cases it indicates a term of opposite meaning.

3. Rather than providing citations for each new entry in the expanded list of terms, the additional sources used will be included in the References section, with the primary sources�those from which multiple entries were obtained�indicated in boldface.

4. Individual citations are included in a few entries for which the terms and/or definitions are specific to, or originally published in, the cited sources.

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abaxial. Side of an organ facing away from a central axis, e.g. lower side of a leaf or leaflet. Cf. adaxial.

abaxial face. Upper side of a sporophyll. Cf. adaxial face.

abscission. Physiological process in which a corky cell layer forms across an axis, cutting off water and nutrient supply to the distal portion and resulting in its loss, as in loss of a leaf, leaf-like organ, or section of stem.See also deciduous.

abscission layer. Region of tissue designed to separate cleanly, e.g. theleaf bases of most cycad species.

acanthos. Greek, meaning �spine�, e.g. the root word for the second part of the specific epithet of Cycas brachyacantha, referring to the characteristically short petiolar spines. See also brachys.

acaulescent. Without any evident trunk or stem. See also hypogeous. Cf. caulescent, epigeous.

acroscopic, adj. acroscopically. Facing upwards, towards the apex of the axis on which it is borne. Cf. basiscopic.

aculeate. Having sharp prickles, e.g. the petiole of Cycas aculeata.

acuminate. Tapering to a protracted point, with sides somewhat concave, e.g. the leaflets of Zamia acuminata. Cf. acute.

acute. Narrowing to end in a sharp point, as for the leaflets of many cycad species. Cf. acuminate.

adaxial. Side of an organ facing toward a central axis, e.g. the upper side of a leaf or leaflet. Cf. abaxial.

adaxial face. Lower side of a sporophyll. Cf. abaxial face.

adult. Reproductive life cyclestage having a visible stem (erect in arborescent species) and leaves arranged in one or more well-developed cohorts or crowns (sensu Y��ez-Espinosa, 2009); mature.Cf. juvenile, seedling.

adult leaf. Leaf of a mature plant that is typical in form (but different from those of juvenile plants, offsets, and/or suckers of the same species). Cf. juvenile leaf.

adventitious bud. Vegetative growth arising on a cycad stem, giving rise to suckers at the base or offsets on the aerial stem.

aemulans. Latin, meaning �equalling�, e.g. the specific epithet of Encephalartos aemulans, referring to its similar male and female cones.

aerial. Above-ground; in cycads, referring to arborescent stems. See also caulescent, epigeous. Cf. acaulescent, hypogeous.

aerial branch. Uncommonly used term for a well-developed offset. Cf. sucker.

after-ripening period. Period of time after the seeds dehisce from the female cone during which the pro-embryo continues to grow and develop into a mature embryo.

alate, aliferous. Winged, e.g. the thin appendage of tissue below the terminal facet of Encephalartos pterogonus microsporophylls.

alternate. Leaflets borne singly and not spaced opposite each other along the rachis.Cf. paired.

amblys. Greek, meaning �blunt�, e.g. the root word of the first part of the specific epithet of Zamia amblyphyllidia, though technically referring to leaves, this epithet actually refers to the obovate leaflets which lack a sharp point at the apex. See also phyllon.

amplus. Latin, meaning �ample� or �large�, e.g. the root word of the first part of the specific epithet of Zamia amplifolia, while originally intended to refer to the very large leaflets, the epithet actually refers to the leaves but is really not a misnomer. See also folium.

angular. Having evident ridges;angled. See also facet.

angulatus. Latin, meaning �angled�, e.g. the root word of the specific epithet of Cycas angulata, referring to the strong leaflet angle of insertion.

angustus, angusti-. Latin, meaning �narrow�, e.g. the root word of the specific epithets of Dioon angustifolium and Zamia angustifolia, though technically referring to leaves, these epithets actually refer to the narrow leaflets. See also folium.

apex, plural apices. Tip; distal end of an organ such as a shoot, leaf, or root; in cycads, also the growing point of the caudex.

apical. Arising from or positioned at the tip; terminal, e.g. the most distal leaflets on a cycad leaf. Cf. basal, median,proximal.

apiculate. Having a short, sharp, flexible point (= apiculum), e.g. as in the female cones of Ceratozamia matudae.

apogeotropic, ageotropic, apogravitropic. Developing in an orientation contrary to gravitational force, e.g. cycad coralloid roots.

appressed. Pressed closely to another organ but not united, e.g. the exposed portion of the sporophylls of female Dioon cones.

arborescent. Tree-like in habit, e.g. all cycads in the genus Dioon. See also caulescent, epigeous. Cf. acaulescent,hypogeous.

arching. Forming an arch; in cycads, used to describe the natural orientation of a leaf or the most recent crown or flush of leaves, e.g. the crown of_Ceratozamia kuesteriana_. Cf. ascending, erect, spreading.

arcuate. Having the form of a bow; curved, e.g. the leaves of Zamia sandovalii when growing on level ground (as opposed to the typical pendent habit of the leaves of this primarily cliff-dwelling species). See alsoarching. Cf. ascending, erect, spreading.

argenteus. Latin, meaning �of silver�, e.g. the root word of the specific epithet of Dioon argenteum, referring to the persistent silvery tomentum on the leaves.

armed. Having spines or prickles, e.g. the prickles of some cycad petioles and the serrations or teeth of some cycad leaflets. Cf. inerm.

armor. Colloquial, referring to a collection of persistent leaf bases that �protect� a caudex.

articulate. Separated by a node or joint, e.g. theleaflets of Ceratozamia, Chigua, Microcycas,and Zamia are articulated at the base.

ascending. Arched upwards in the lower part and becoming erect in the upper part; in cycads, used to describe the natural orientation of the most recent crown or flush of leaves (e.g. as in Encephalatos heenanii) or the exposed tip of microsporophylls (e.g. as in Cycas wadei). Cf. arching, erect, spreading.

attenuate. Tapering gradually, e.g. the median leaflets of Zamia tuerckheimii.Cf. acuminate.

aurea. Horticulturally desirable mutation in which the leaflet tips are bright yellow instead of green.

axillary. In cycads, relating to the cones of certain species that arise from between the leaves rather than at the stem apex, e.g. many species of Encephalartos and Macrozamia.

�baggie method�. Method of cycad seed germination in which seeds are stored in slightly damp peat moss inside ziplock baggies until the hypocotyl emerges, at which time they are removed and potted.

bare-root. Process of removing soil from the roots of a plant in preparation for shipping; any such plant that has been bare-rooted.

barrel-shaped. In the shape of a barrel, widest in the middle and tapering at both ends; often used in reference to cones or trunks, e.g. the female cones of Encephalartos laevifolius.

basal. Arising from or positioned at the base; used in reference to the most proximal leaflet(s) on a cycad leaf. Cf. distal, median,terminal.

basal blotch. Light-colored tissue at the point of articulation of a leaflet,e.g. as in most species of Macrozamia.

basiscopic, adj. basiscopically. Facing the base of the axis on which it is borne.Cf. acroscopic.

bicornate. With two horns, e.g. the sporophylls of Ceratozamia cones.

bifid. Deeply notched or cleft for more than half the length, e.g. the leaflets of Cycas bifida.

bifoliolate. Having two leaflets, e.g. the eophylls of many cycad species.

bifurcate. Forked in a Y-shaped manner, usually applying to leaves, leaflets, or stems (e.g. the leaflets of Cycas micholitzii); with two terminal, long lobes (e.g. the apices of some_Encephalartos hildebrandtii_ leaflets).

bijugate. Of a pinnate leaf with two pairs of leaflets, e.g. the eophylls of some cycad species. See also jugate.

bilateral. Having or formed of two sides; two-sided, e.g. the seeds of Cycas.

bipinnate. Twice pinnate; of a compound leaf having both first order and second order divisions, i.e. pinnae and pinnules, e.g. both Bowenia speciesand some Cycas species.See also multipinnate.

biserrate. Doubly serrate; with smaller regular, asymmetric teeth on the margins of larger teeth, e.g. the leaflet margins of Zamia disodon.

bisulcate. Cleft or cloven, as a hoof, e.g. the adaxial side of the rachis of some Ceratozamia species.

blade. Lamina; part of theleaf distal to the sheath or petiole.

brachys. Greek, meaning �short�, e.g. the root word of the first part of the specific epithet of Cycas brachyacantha, referring to the characteristically short petiolar spines. Cf. acanthos.

branched, branching. Possessing lateral or aerial branches, e.g. the trunks of some Cycas species. Cf. solitary, unbranched.

brevis. Latin, meaning �short�, e.g. the root word of the first part of the specific epithet of Encephalartos brevifoliolatus, referring to its relatively short leaflets. See also foliola.

brunneus. Latin, meaning �brown�, e.g. the root word of the specific epithet of_Cycas brunnea_, referring to the brownish trichomes on the new growth.

bubalinus. Latin, meaning �buff�, e.g. the specific epithetof Encephalartos bubalinus, referring to the buff-colored tomentum on the cataphylls and leaf bases.

bulb. Storage stem of limited longitudinal growth enveloped in fleshy leaf bases; misapplied to the bulbous trunks of some Cycas species, and occasionally misapplied to cycad suckers or leafless and rootless cycad caudices ready to be shipped.

bulbous. Swollen to an almost spherical shape, e.g. the trunk base of Cycas pachypoda and several other Asian cycads.

bulla, plural bullae. Bubble, blister or vesicle; commonly used in reference to the expanded shield-like distal portion of some cycad sporophylls, e.g. Encephalartos sporophylls (Melville, 1957); although the derivation is technically incorrect, this term has become widely entrenched in cycad literature, and its continued use is recommended.

caespitose. Turf-shaped and forming a clump, as in many suckering cycads, e.g. Ceratozamia norstogii or Encephalartos cupidus.

callous (adjective)**.**Of the distinctive swollen tissue, often colored, formed at the point of insertion of Macrozamia leaflets onto the rachis; often confused with callus.

canaliculate. Longitudinally channeled or grooved, e.g. the leaflets of_Ceratozamia mirandae_.

**_candida_.**Greek, meaning �white�, _e.g._the specific epithet of Cycas candida, referring to the white seeds.

canescent. Gray or white in color due to a covering of short, fine, gray or white hairs, e.g. the male cones of Zamia cupatiensis.

carinate. Shaped like or having a carina or keel; ridged, e.g. the sclerotesta of_Cycas wadei_. See also ribbed.

cataphyll. Modified leaf, much reduced and thickened, serving to protect the apical meristem in cycads and usually produced in flushes preceding the emergence of cones or leaves.

caudate. Having a tail or tail-like appendage, e.g. the leaflet apices of Cycas multipinnata andboth species of Chigua. Cf. drip tip.

caudex. Thick stem or trunk, often at least partially subterranean.

caulescent. Having an above-ground trunk or stem. See also arborescent,epigeous. Cf. acaulescent, hypogeous.

ceratos. Greek, meaning �horn�, e.g. the root word of the first part of the generic name Ceratozamia, in reference to its characteristic bicornate sporophylls.

cerina. Latin, meaning �wax�, e.g. the root word of the specific epithet of Encephalartos cerinus, referring to the heavy waxy coating that gives the leaves a bluish color.

chalaza. Proximal end of a seed; its point of attachment, e.g. the seeds of Dioon mejiae have a characteristic enlarged chalaza. Cf. coronula, micropyle.

chamal. Vernacular name for Dioon edule by the xi�iuy indigenous people in San Luis Potos�, Mexico, who use the seeds to make a variety of foodstuffs (Y��ez-Espinosa, 2009).

channeled. With raised longitudinal edges to form a channel, as in the adaxial surface of many cycad petioles and the leaflets of certain cycad species,e.g. the leaflets of Ceratozamia kuesteriana.

chartaceous. Papery in texture, e.g. the leaflets of Zamia vazquezii. See also membranous, papyraceous. Cf. coriaceous.

**_chiera._**Greek, meaning �hand�, e.g. the second part of the specific epithet of Zamia macrochiera,referring to the large, gland-like collar separating the leaflets from the petiolules.

circinate. Rolled in a coil-like manner with the apex innermost, e.g. the leaflets of emerging leaves of Cycas species (hence C. circinalis). See also conduplicate, inflexed, reflexed.

clivis. Latin, meaning �cliff�, e.g. the root word of the first part of the specific epithet of Cycas clivicola, referring to the cliff-dwelling habit and habitat.

clumping. Vegetative production of suckers or offsets; habit of such a plant, often forming a clump; suckering. Cf. solitary.

cohort. A group of individuals of the same age recruited into a population at the same time; also pertaining to a group of leaves produced at the same time or in the same growing season. See also crown, flush.

coleorrhiza. Hard disk or cap of cells covering the shoot apex of a cycad embryo.

collar. In cycads, a colored or textured band at the base of a leaf (e.g. as in Encephalartos lehmannii), or a glandular swelling at the base of a leaflet (e.g. as in Zamia manicata).

columnar. In cycads, referring to the column-shaped trunk of some arborescent species.

communis. Latin, meaning �common�, e.g. the specific epithet of Macrozamia communis, referring to its abundance in dense stands.

compound leaf. Leaf composed of a rachis and some number of opposed blades (leaflets or pinnae).

compressed. Flattened, e.g. the sporophylls of_Dioon_ female cones, or the oldtrunk bases of large, arborescent cycads.

concinnus. Latin, meaning �neat� or �trim�, e.g. the specific epithet of Encephalartos concinnus and Macrozamia concinnus, referring to the compact and attractive habit.

concolorous. Uniformly colored, as in upper and lower surfaces, e.g. the leaflets of most cycad species. Cf. discolorous.

conduplicate. Folded together lengthwise, usually in two equal halves, e.g. the leaflets of emerging Stangeria leaves or the tips of the emerging leaves of some species of Zamia. See alsocircinate, inflexed, reflexed.

cone. Reproductive structure of gymnosperms; organized collection of sporophylls on a central axis. See also strobilus, megasporangiate and microsporangiate strobili.

cone scale. Colloquial forsporophyll.

conferted. Closely crowded, e.g. the leaflets of Macrozamia conferta and_Encephalartos sclavoi_.

conic, adj. conical. Of a 3-dimensional structure that is cone shaped, attached at the broader end,e.g. the shape of some cycad strobili.

coning. Act of producing acone; of a plant that is producing a cone. See also phenology.Cf. flushing.

connate. Joined or united with a structure of the same kind, e.g. the terminal leaflets of Stangeria leaves.

contracted. Narrowed, reduced in size, or pulled together, e.g. the leaflet bases of Macrozamia pauli-guilielmi and many other cycad species.

coralloid root. Club-shaped apogravitropic(apogeotropic) root with the potential for hosting symbiotic cyanobacteria; specific to the Cycadales.

coriaceous. Leathery in texture, e.g. the leaflets of Encephalartos laurentianus.Cf. chartaceous, membranous, papyraceous.

corniculate. Having horn-like projections, e.g. the sporophylls of Ceratozamia, which are characteristically bicornate.

coronula. Crown-like, segmented cap over the embryo-containing cavity of a cycad seed.See also micropyle. Cf. chalaza.

corrugated. Shaped into wrinkles or folds, or alternating ridges and grooves, e.g. the leaflets of Zamia skinneri. See also plicate.

corruptule. Unfertilized ovule that is superficially indistinguishable from a trueseed. See also omnule.

cotyledon. Seed leaf; the first embryonic leaf of a plant embryo. See alsoeophyll. Cf. euphyll.

crack. Colloquial, in reference to the spaces between megasporophylls occurring when a female cone becomes receptive to pollination.

creeping. Colloquial forprocumbent or prostrate. Cf. erect.

cremnophyte, adj. cremnophilous. Cliff-dwelling plant, e.g. Zamia cremnophila.

crenate. Having rounded teeth, e.g. the megasporophyll margins of Cycas micronesica. See alsocrenulate. Cf. spinose.

crenulate. Having minute rounded teeth, e.g. the megasporophyll margins of Cycas thouarsii. See also crenate. Cf. spinulose.

crested, cristate. Mutation that causes leaves and cones to be produced in alinear rather than radial symmetry.

crowded. Clustered close together, e.g. the leaflets of Cycas conferta and Encephalartos sclavoi.

crown. Group of leaves produced at the same time or in the same growing season; sometimes referring to the entire set of leaves held by a plant, or to the apex of the caudex bearing the leaves. See also cohort, flush.

cuneate. Wedge-shaped and attached at the narrow end, e.g. the point of attachment of many cycad leaflets.

cupidus. Latin, meaning �desirable�, e.g. the specific epithet of Encephalartos cupidus, referring to its striking form, thought by the author to render it desirable to cycad collectors.

cuspidate. Terminating in or tipped with a sharp, firm point, e.g. the leaflets of Macrozamia heteromera, the female cones of Zamia tuerckheimii, and the microsporophyll apices of Cycas revoluta and C. taitungensis.

cylindric, adj. cylindrical. Of a 2-dimensional structure that is tubular or rod-shaped,e.g. many cycad microstrobili.

deciduous. Used of structures shed at regular intervals, or at a given stage of development,e.g. the older leaves of Cycas xipholepis.

declinate. Gently curving downward (abaxially), e.g. the leaflets of Dioon tomasellii. Cf. deflexed, inflexed, reflexed.

decumbent. Of stems, lying along the ground but turning upwards distally, e.g. the stems of Ceratozamia decumbens and numerous other species. See also procumbent,prostrate. Cf. erect.

decurrent. Extending basipetally from the point of insertion, e.g. Lepidozamia leaflets, where the leaflet base extends downward along the rachis.

decussate. Of leaves or other lateral organs, in opposite pairs, the successive pairs being borne at right angles to each other. Cf. alternate, opposite.

deflexed. Bent abruptly downward (abaxially), e.g. the microsporophylls of Cycas panzhihuaensis and the apicalleaflets of Dioon rzedowskii. Cf. declinate, inflexed, reflexed.

dehiscence, adj. dehiscent. Rupturing process where the contents of a plant structure are released, e.g. pollen shedding from amature male cone, or seeds dropping from a mature female cone. Cf. receptive.

deltoid. Of a 3-dimensional structure that is triangular or delta-shaped, e.g. themicrosporophylls of many Cycas species.

dentate. Having sharp indentations or teeth along the edge of a structure and perpendicular to its margin, e.g. the leaflet margins of Encephalartos whitelockii. See also serrate.

denticulate. Finely dentate, e.g. the leaflet margins of Dioon spinulosum.See also serrulate.

descending. To slope, extend, or incline downward (abaxially), e.g. the megasporophylls of Encephalartos sclavoi. Cf. ascending.

dichotomous. Branching into two equal parts, e.g. the forked branching of Cycas elongata stems, Cycas bifida leaflets,or Cycas segmentifida megasporophyll lobes; also used in reference to branching patterns in dendrograms.

dichotomous key. Structured system of deducing the correct species assignment among a number of related species, also known as a diagnostic or taxonomickey.

dimorphic. Having two different forms, e.g. the distinctly different male andfemale cones of most cycad species.

dioecious. Having microsporangia and megasporangia on different plants, e.g. all extant cycads.

diplo-. Greek, meaning �double�, e.g. the first part of the specific epithet of Macrozamia diplomera, referring to the dichotomously divided leaflets.

dis. Greek, meaning �two�, e.g. the root word for the first part of the generic name_Dioon_, referring to the paired seeds on each megasporophyll.See also oon.

disarticulate. To separate at the joints; to become disjointed, e.g. the process of a mature female cone opening to allow the seeds to drop. See also dehisce. Cf. indehiscent, receptive.

discolorous. Having two colors, often referring to the lower (abaxial) leaf or leaflet surface being distinctly different in color from the upper (abaxial) surface, e.g. the leaflets of Ceratozamia fuscoviridis and Encephalartos transvenosus. Cf. concolorous.

dissected. Composed of numerous segments, as a compound leaf and its leaflets (or pinnae).

distal. Furthest away fromthe center of a structure or, more commonly, furthest from its point of attachment. See also apical, terminal.Cf. basal, proximal.

divaricate. Widely spreading, e.g. the horns on immature microsporophylls of Ceratozamia mixeorum.

divided. Separated down to the point of attachment, e.g. the leaflets of Cycas bifida.See also bifid,compound leaf, pinnate.

dolichos. Greek, meaning �long�, e.g. the root word of the first part of the specific epithet of Cycas dolicophylla, referring to its long leaves. See also phyllon.

drip tip. Thin, protracted tip of the leaves (or leaflets) of many rainforest plants, e.g. the leaflets of Ceratozamia hondurensis.

drooping. Bent or hanging downward (abaxially), e.g. the leaflets of Ceratozamia kuesteriana, the leaves of Cycas lane-poolei, and the lips of the terminal facets of the sporophylls of Encephalartos aplanatus. See also declinate, deflexed.Cf. inflexed, reflexed.

dry pollination. Type of hand pollination whereby pollen is introduced to a female cone in powder form, often by means of pouring or blowing into the open spaces (cracks) between the sporophylls of a receptive cone.

dwarf. Small stature or habit, e.g. Zamia pygmaea.

elegans. Latin, meaning �elegant�, e.g. the specific epithet of Macrozamia elegans and the root word of the first part of the specific epithet of Zamia elegantissima, referring to the neat and pleasing habit.

ellipsoid. Of a 3-dimensional structure that is widest near the middle but narrowed towards each rounded end, e.g. the seeds of Cycas wadei.

elliptic. Of a 2-dimensional structure that is widest near the middle but narrowed towards each rounded end, e.g. the leaflets of Zamia amplifolia.See also obovate, ovate.

elongate. Lengthened or drawn out, e.g. the apical spines of Cycas elongata megasporophylls.

elongation. In cycads, rapid growth of**male cones** just prior to dehiscence, or rapid growth of developing**leaves** during emergence.

emarginate. Having a shallow notch at the apex, e.g. as in the sarcotesta of_Cycas revoluta_, and the leaflets of Zamia pygmaea.

embryo. In seeds, diploid tissue arising from the zygote**,** until the time of germination.

emergent. Said of a trunk when it extends above ground level; of a tree that extends above the canopy of surrounding trees.

emergent leaf color. Color of the leaflets of newly emerging leaves; though this is sometimes characteristic for a given taxon(e.g. Zamia imperialis), other times different colors can occur in the same species or population(e.g. Z. standleyi).

emerging. In cycads, early development of a cone or flush of leaves; immature cone or flush.

entire. With a continuous margin; not toothed or lobed, e.g. the leaflets of the mature leaves of Dioon edule and all species of Cycas.

eophyll. First leaf produced by a seedling. See also euphyll.

epicotyl. That part of a plant embryo above the insertion of the cotyledon. Cf. hypocotyl, mesocotyl.

epigeous. Occurring above soil level, as for the stems of arborescent cycads. See also caulescent. Cf. acaulescent,hypogeous.

epiphyte, adj. epiphytic. Plant growing on another plant non-parasitically, or on some other elevated support, e.g. Zamia pseudoparasitica.

erect. Upright; perpendicular; in cycads, used to describe the natural orientation of stems (_e.g._the trunk of Dioon merolae) or of the most recent crown or flush of leaves (e.g. the crown of Ceratozamia norstogii). Cf. decumbent, procumbent, prostrate (pertaining to stems);arching, ascending, spreading (pertaining to leaves).

_erio_-. Greek, prefix meaning �woolly�, e.g. the first part of the specific epithet of Stangeria eriopus, referring to the woolly leaf bases. See also �pus.

etiolated. Abnormally elongated leaf resulting from a plant grown under low light intensity.

euphyll. Conventional foliage leaf, not modified in any way.See also eophyll.

eurys. Greek, meaning �broad�, e.g. the root word for the first part of the specific epithet of Ceratozamia euryphyllidia, though technically referring to leaves, the epithet actually refers to the extraordinarily broad leaflets. See also phyllon.

ex situ. Latin, of plants or plant collections in cultivation outside their natural habitat. Cf. in situ.

excurrent. Extending beyond the apex of a leaf, e.g. the rachis of Ceratozamia matudae.

explinate. Spreading or extending outwardly in a flat form, e.g. thelateral facets of the megasporophyll bullae of Encephalartos inopinus.

exsiccatum, plural exsiccata. Latin, pertaining to dried specimen material; plantae exsiccatae refers to herbarium specimens.

exudate. Substance that has oozed forth, e.g. mucilage exuding from a wound on a cycad caudex.

F1, F2. Hybrid progeny of the first or second filial generation of a plant cross, respectively, e.g. Encephalartos natalensis x woodii.

face. Colloquial for the terminal facet of a sporophyll bulla.

facet. Flattened terminal,median, or lateral section of a sporophyll bulla defined by ridges (Melville, 1957). See also latero-sagittal ridge,medio-sagittal ridge, sagittal ridge.

falcate. Curved in a sickle shape, e.g. the leaflets of Cycas falcata.

farinaceous. Having the texture offlour or similar starchy material; sometimes referring to a dusty covering;mealy.

fasciculate. Arranged in a whorl, e.g. the leaflets of the common form of Ceratozamia hildae.

feeder root. One of the numerous small roots of a plant, through which moisture and nutrients are absorbed from the soil. Cf. taproot.

female cone. Seed-bearingstrobilus. See also megasporangiate strobilus, ovulate cone, seed cone. Cf. microsporangiate strobilus, pollen cone.

ferox. Latin, meaning �fierce�, e.g. the specific epithet of Encephalartos ferox, referring to the stiff, sharply spiny leaflets.

ferrugineous. Rusty brown in appearance, e.g. the tomentum at the stem apex of_Cycas ferruginea_.

fertile. In cycad biology, that portion of the cone (or in Cycas, the megasporophyll) that produces gametes. Cf. sterile.

flabellate. Fan-shaped,e.g. the megasporophyll blade of some Cycas species.

flat. In cycads, a leaflet margin that is not curved or curled in any way; leaflets oriented straight out from the rachis in cross section. Cf. involute, revolute,sinuate, undulate (leaflet margins); declinate, keeled,secund (leaf cross section).

flexuose, flexuous. Of zig-zag shape, e.g. alluded to in the much twisted rachis of Macrozamia flexuosa.

flotation layer. Tissue layer of the sarcotesta of some Cycas seeds that makes them naturally buoyant, e.g. as in Cycas mironesica. See also spongy endocarp.

floccose. Bearing soft, uneven hairs, e.g. thecataphylls of Cycas cairnsiana.

flush, flushing. In cycads, a group of newly emerging leaves; also used in reference to a cohort of leaves. Cf. coning.

foliola. Latin, meaning �leaflet�, e.g. the root word of the second part of the specific epithet of Encephalaros brevifoliolatus, referring to its relatively short leaflets. See also brevis.

folium, folius. Latin, meaning �leaf�, e.g. the root word of the second part of the specific epithet of Ceratozamia latifolia, though technically referring to leaves, this epithet actually refers to the distinctively broad leaflets. See also ceratos.

forked. Divided into equal or nearly equal halves, e.g. the leaflets of Cycas bifida.See also bifid, bifurcate.

frass. Debris and fecal matter produced by insects, e.g. the characteristic accumulation of frass and mucilage exudate on the surface of cycad stems infested with stem borers.

fringed. In cycads, a margin of tissue protruding from the terminal facet of the sporophylls, e.g. Encephalartos villosus.

frizzletop. Micronutrient deficiency caused by a lack of available manganese in the soil, easily treated by applying manganese sulfate.

fulvous. Dull brownish-yellow, e.g. the male cones of many Zamia species.

fungal leaf spot. Fungal disease, often of Zamia, caused by Mycoleptodiscus or other fungi that cause well-defined areas of tissue to die creating noticeable spots.

funiculus, plural funiculi. Attachment stalk of an ovule. See also stipe.

furfuraceous. Covered with bran-like scales or powder, e.g. the emergent foliage of_Cycas furfuracea_ and Zamia furfuracea.

fuscous. Dark grayish-brown, dusky, e.g. the color of the abaxial surface of the leaflets of Ceratozamia fuscoviridis.

fusiform. Spindle-shaped; narrowed at each end and swollen centrally, e.g. as in the male cones of Cycas taitungensis and many other Cycas species.

germinate, germination. Process by which the embryo resumes growth and escapes from the confines of the seed and the young seedling is established.

germinated seed. Of a cycad seed that has begun to germinate, indicating that it is viable.

glabrate. Glabrous, but obviously having previously had an indumentum. Cf. glabrescent.

glabrescent. Still with hairs, but losing them and in the process of becoming glabrous. Cf. glabrate, pubescent.

glabrous. Of a smooth surface, without hair of any kind, e.g. the mature leaves of most cycad species. See also nitidus. Cf. lanate, pilose, pubescent, sericeous, tomentose.

glaucescent. Becomingglaucous. Cf. nitidus.

glaucous. Of a surface covered by a bluish-gray waxy or powdery bloom, e.g. the leaves of Macrozamia glaucophylla. See also pruinose.Cf. nitidus.

globose. Nearly spherical; globular, e.g. the seeds of Cycas siamensis or the pseudocone of Cycas panzhihuanensis.

gratus. Latin, meaning �pleasing�, e.g. the specific epithet of Encephalartos gratus, referring to its pleasing appearance.

hand pollination. Anthropogenic pollen transfer for the purpose of producing viable cycad seeds via artificial propagation.

**herbarium specimen.**A representative sample (usually dried) of a plant, usually from a specific population or locality. See also exsiccatum, holotype, plantae exsiccatae, type.

heteros. Greek, meaning �different�, e.g. the root word of the first part of the specific epithet of Macrozamia heteromera, referring to its divided and undivided leaflets. See also �merus.

hexagonal. Having six sides, e.g. the 2-dimensional profile of most cycad megasporophylls(except Cycas).

hirsute. Covered with short coarse hairs, e.g. the leaves of Encephalartos hirsutus. See also lanate, pilose, pubescent, sericeous,tomentose. Cf. glabrous, nitidus.

hoary. Covered with grayish hair or pubescence, e.g. the emerging leaves of Cycas basaltica.

holotype, holo. Single herbarium specimen or illustration of the type collection used or designated by the author of the name.

horns. In cycads, sharp protrusions on the sporophylls, e.g. the genus Ceratozamia is characterized by two horns per sporophyll (= bicornate).

horridus. Latin, meaning �horrible�, e.g. the specific epithet of Encephalartos horridus, referring to its stiff, spiny leaflets.

humilis. Latin, meaning �humble� or �lowly�, e.g. the specific epithet of both Macrozamia humilis and Encephalartos humilis, referring to the small stature.

hybrid. Natural or artificially produced plant resulting from a cross of genetically-dissimilar parents, commonly between two different species.

hydrophyte, adj. hydrophytic. Plant adapted to grow in water, e.g. Zamia nesophila is adapted to growing in standing seawater for extended periods when its beach strand habitat becomes inundated during regularly occurring storms.

hymen. Greek, meaning �thin� or �membranous�, e.g. the first part of the specific epithet of Zamia hymenophyllidia, though technically referring to leaves, this epithet actually refers to the extremely thin, almost transparent leaflets. See also phyllon.

hypocotyl. That part of a plant embryo below the cotyledon but above the root. Cf. epicotyl, mesocotyl.

hypogeous. Occurring below soil level; subterranean, e.g. the stems of Stangeria eriopus, many Zamia species, and most Macrozamia Section Parazamia species. See also acaulescent. Cf.arborescent, caulescent, epigeous.

imbricate. Overlapping,e.g. the leaflets of many Encephalartos species.See also incubous, succubous.

imparipinnate. Of aleaf or leaflet where the rachis or rachilla terminates in a solitary pinna or pinnule, e.g. seedling leaves of Cycas cairnsiana. Cf. paripinnate.

in situ. Latin, of plants growing naturally in their native habitat. Cf. ex situ.

incised. Deeply and sharply cut, e.g. the leaflets of Cycas micholitzii. Cf. pinnate.

incubous. Arrangement in which a leaflet partially shields the next distal leaflet when viewed from above (adaxially), e.g. as in Dioon califanoi and Encephalartos hirsutus. Cf. succubous.

incurved. With apex bent or curving upward (adaxially), e.g. the tips of the median microsporophylls of Macrozamia platyrachis. Cf. recurved.

indumentum. Covering of (often pigmented) trichomes or scales. See also tomentum.

inerm. Without spines or prickles; unarmed, e.g. the petioles of Zamia inermis. Cf. armed.

inflexed. Bent longitudinally inwards (adaxially), e.g. emerging leaves of many Encephalartos and Zamia species. See also circinate, conduplicate. Cf. declinate,deflexed, reflexed.

internode. Part of an axis between two successive nodes, joints, or points of attachment of leaves or leaflets. Cf. node.

involute. With margins rolled inwards (adaxially), e.g. as in Cycas revoluta var. involuta. Cf. revolute.

jugate. Of a pinnate leaf; having leaflets in pairs, e.g. as in most cycad species.

juvenile. Non-reproductive life cycle stage with no visible stem (or barely visible) and leaves arranged in one or more well-developed cohorts or crowns (sensu Y��ez-Espinosa, 2009). Cf. adult, mature, seedling.

juvenile leaf. Leaf of a young plant (and of offsets and suckers) that is different in form from those of an adult. Cf. adult leaf.

karpos. Greek, meaning �fruit�, e.g. the root word of the second part of the specific epithet of Cycas macrocarpa, though cycads do not technically have fruit, this epithet actually refers to the large seeds.See also mega.

keeled. V-shaped; resembling a boat keel; secund, e.g. the leaves of Dioon califanoi and Encephalartos lehmannii. See also pinna-pinna (pp) angle. Cf. declinate, deflexed, reduplicate.

laciniate. Cut into narrow segments, e.g. the megasporophyll blades of many _Cycas_species.

laevis. Latin, meaning �smooth�, e.g. the root word of the first part of the specific epithet of Encephalartos laevifolius, referring to the lack of tomentum on the leaves. See also folius.

lamina, plural laminae. Flattened and expanded portion of a leaf, leaflet, or sporophyll;blade.

lanate. Woolly with long, intertwined, curly hairs, e.g. the stem apex, emergent leaves, and cones of Encephalartos lanatus. See also hirsute, pilose, pubescent, sericeous, tomentose. Cf. glabrous, nitidus.

lanceolate. Lance-shaped, much longer than broad, with a wide base, tapered apex, and widest below the center, e.g. the median leaflets of_Cycas petraea_. See also oblanceolate.

lateral facet, lateral angle. Side surfaces of sporophyll bullae (Melville, 1957).Cf. median facet, terminal facet.

lateral lobe. Side projection of a megasporophyll. Cf. median lobe, sagittal crest.

latero-sagittal ridge. Line, sometimes more distinct than others, separating the median facet from the lateral facets of Encephalartos sporophyll bullae (Melville, 1957). Cf. medio-lateral ridge,sagittal ridge.

latus. Latin, meaning �wide�, e.g. the root word of the first part of the specific epithet of Ceratozamia latifolia, though technically referring to leaves, the epithet actually refers to the broad leaflets. See also folium.

leaf. Usually green, flattened, lateral structure attached to a stem and functioning as a principal organ of photosynthesis and transpiration in most plants.

leaf base. Often swollen point of attachment of the leaf to the caudex. See also collar.

leaf miner. Tiny grub that tunnels in young cycad leaves leaving whitish blotches or trails.

leaf scar. Colloquial for persistent leaf base, with or without an abscission, often forming rings on arborescent caudices corresponding to successive flushes.

leaf stalk. Stalk of aleaf; petiole.

leaflet. Primary division of a compound leaf; pinna.

leggy. Colloquial for a plant growing tall and spindly, usually from inadequate sunlight; etiolated.

lenticular. Shaped like a biconvex lens, e.g. the nodules of coralloid roots.

ligulate. Strap- or tongue-shaped, e.g. the leaf outline of many cycad species.

linear. Long and narrow, the sides parallel or nearly so, e.g. the leaflets of Zamia angustifolia.

lip. Colloquial, in cycads, a margin of tissue protruding from the terminal facet of the sporophylls, e.g. as in Encephalartos villosus.

lobate, lobed. Having lobes; lobed, e.g. the leaflets of Encephalartos arenarius. Cf. entire.

long-stalked. Colloquial, pertaining to a long peduncle. Cf. sessile,short-stalked.

lucid. Shining or glowing,e.g. the leaflets of Macrozamia lucida or Zamia splendens. Cf. glaucous.

male cone. Pollen-bearingstrobilus. See also microsporangiate strobilus, pollen cone. Cf. female cone, megasporangiate strobilus, ovulate cone, seed cone.

manicatus. Latin, meaning �long-sleeved�, e.g. the root word of the specific epithet of Zamia manicata, referring to the presence of a petiolule.

mature. Capable of sexual reproduction; adult. Cf. juvenile, seedling.

mealy. Covered with fine, flour-like powder; farinaceous.

mealybug. Any of the scale insects belonging to the Family Pseudococcidae that have a white powdery covering and are destructive plant pests, _e.g._especially of species like Zamia furfuracea that have densecrowns of leaves.

median. Arising from or positioned at the midpoint; used in reference tothe leaflets occurring in the mid-portion of a cycad leaf; also used in statistics for that value of a variable in an ordered array that has an equal number of observations or items above it or below it. Cf. apical, basal.

median facet. Flat, angled surface above the terminal facet of a sporophyll bulla (Melville, 1957). Cf. lateral facet.

median lobe. Central projection of the adaxial face of a megasporophyll. Cf. lateral lobe, sagittal crest.

medio-lateral ridge. Line, sometimes more distinct than others, forming the lower edge of the terminal facet of Encephalartos sporophyll bullae (Melville, 1957). Cf. latero-sagittal ridge, medio-lateral ridge, sagittal ridge.

mega. Greek, meaning �large�, e.g. the root word of the first part of the specific epithet of Cycas megacarpa, referring to the distinctive large seeds. See also karpos.

megagametophyte. Mass of haploid cellular tissue surrounding the embryo in a gymnosperm seed; analogous in function but not in origin to the endosperm of angiosperm seeds.

megasporangiate strobilus, less correctly megastrobilus. Seed-bearing cone, seed cone, or ovulate cone; less correctly female cone.Cf. microsporangiate strobilus.

megasporophyll. Sporophyll bearing one or more ovulesor later seeds, or potentially so. Cf. microsporophyll.

_melano_-. Greek, meaning �black� or �very dark�, e.g. the first part of the specific epithet of Zamia melanorachis, referring to the dark brown to almost dark purple rachis.

membranous, less commonly membranaceous. Thinly textured, as in a membrane, e.g. the leaflets of Ceratozamia euryphyllidia. See also chartaceous, papyraceous. Cf. coriaceous.

mesocotyl. That part of the axis of an embryo that bears the cotyledon. Cf.epicotyl, hypocotyl.

micronutrient deficiency. Symptom(s) expressed in plants not receiving sufficient quantities of a particular micronutrient. See also frizzletop.

micropyle. Orifice in the integuments and later seed coats, at the distal end of a cycad ovule, through which the pollen or pollen tube enters. See also coronula. Cf. chalaza.

microsporangiate strobilus, less correctly microstrobilus. Pollen-bearing cone, pollen cone; less correctly male cone. Cf. megasporangiate strobilus.

microsporangium, plural microsporangia. Structure on the abaxial surface of microsporophylls containing microspores; pollen sacs.

microsporophyll. Sporophyll bearing microsporangia. Cf. megasporophyll.

midrib, midvein. Main, central vascular supply of a leaflet, e.g. the raised central vein of Cycas leaflets.

�mother� plant. Colloquial, referring to a plant that has produced suckers or offsets that have been removed by division for the purpose of vegetative propagation.

mucilage. Gelatinoussubstance; in cycads comprising complex water-soluble carbohydrates and produced in response to stress or wounding.

mucronate. Ending abruptly in a sharp point or spur known as a mucro, e.g. the pointed apex of some Zamia macrostrobili, and the leaflets of_Cycas basaltica_.

multi-headed. In cycads, a plant (often acaulescent) bearing numerous individual apices, often forming a clump. Cf. solitary.

multipinnate. Of a compound leaf, having more than two orders of division, e.g. the leaflets of_Cycas multipinnata. See also_ bipinnate.

multiseriate. Organized in several rows, as structures of a plant, e.g. the sporophylls of cycad cones.

muricate. With numerous short, hard outgrowths, e.g. the small, sharp teeth of the leaflet margins of Zamia muricata.

mutant. Any organism, gene, or character that has undergone a mutational change, _e.g._the crested or �cristate� mutation causes leaves and cones to be produced in linear rather than radial symmetry.

napiform. Turnip-shaped; large and round in the upper part, and very slender below, e.g. the tuberous, subterranean (hypogeous) caudex of many cycad species.

nerves. Fine veins which traverse the leaf blade.

neuro. Greek, meaning �nerve�, e.g. the first part of the specific epithet of_Zamia neurophyllidia_, though technically referring to leaves, this epithet actually refers to the strongly nerved appearance of the leaflets. See also phyllon.

nitidus. Smooth and shiny,e.g. the adaxial leaflet surface of Zamia splendens.See also glabrous. Cf. glaucous, hirsute, lanate, pubescent, sericeous, tomentose.

node. A point on a stem or leaf where leaves or leaflets originate. Cf. internode.

nodule. Raised bump (_e.g._on the adaxial surface of the leaflets of Encephalartos heenanii) or swelling (e.g. the termini of coralloid roots where the cyanobacteria occur).

oblanceolate. Lance-shaped, much longer than broad, with a wide apex, tapered base, and widest above the center, e.g. the leaflets of Ceratozamia hondurensis. See also lanceolate.

oblique. Having a slanting or sloping direction, course, or position; inclined, e.g. the orientation of the leaflets of Zamia obliqua on the rachis.

obovate. Of a 2-dimensional structure that is egg-shaped in outline but broadest above the middle, e.g. the leaflets of Ceratozamia euryphyllidia.See also elliptic, ovate.

obovoid. Of a 3-dimensional structure that is obovate in longitudinal section, e.g. the seeds of Cycas multipinnata. See also ovoid.

obtrullate. Of a 2-dimensional structure resembling a trowel blade with the broadest axis above the middle and a length:breadth ratio between 3:2 and 2:1, e.g. the microsporophylls of Dioon mejiae. Cf. trullate.

obtuse. Blunt or rounded at the apex, e.g. the leaflets of Stangeria eriopus.Cf. acute.

offset. Vegetative axis arising from an adventitious bud laterally on a cycad trunk; colloquial, pup. Cf. sucker.

omnel. Kernel of an omnule; a �cleaned cycad seed�.

omnule. Collective term formature cycad seeds and fully-expanded unfertilized ovules that are externally indistinguishable; �cycad seed�.

once-pinnate. Simplypinnate; first order of compounding a leaf, such that the pinnae are not themselves further divided, e.g. the leaflets of Cycas bifida. Cf. twice-pinnate.

oon. Greek, meaning �eggs�, e.g. the root word for the second part of the generic name Dioon, referring to the paired seeds on each megasporophyll. See also dis.

opaque. Of veins that do not transmit light when held up to a light source, e.g. of theleaflets of Ceratozamia miqueliana. Cf. transparent.

opposite. Pertaining toleaflets borne directly across from one another on the rachis;paired. Cf. alternate.

orbicular. Nearly circular, e.g. the megasporophyll lamina of Cycas petraea.

ornamental. Used to describe plants, which are planted for their architectural, specimen, or landscape qualities, as opposed to being planted for food or commercial purposes.

ovate. Of a 2-dimensional structure that is egg-shaped in outline but broadest below the middle, _e.g._the leaflets of Zamia vazquezii, or the megasporophyll lamina of Cycas lindstromii. See also elliptic, obovate.

ovoid. Of a 3-dimensional structure that is ovate in longitudinal section, e.g. the male cone of Cycas pectinata. See also obovoid.

ovulate cone/strobilus. Female cone; megasporangiate strobilus.

pachycaulous. Thick-stemmed and columnar but without any substantial secondary wood, e.g. the stems of arborescent cycads.

pachys. Greek, meaning �thick�, e.g. the root word of the first part of the specific epithet of Cycas pachypoda, referring to its distinctive broad trunk base. See also podos.

paired. Having opposite leaflet arrangement. Cf. alternate.

pallid. Pale, e.g. the basal blotch (or callus) on some Macrozamia leaflets and the emergent leaf on some Zamia species.

papyraceous. Papery in texture, e.g. the leaflets of Zamia vazquezii. See also chartaceous,membranous. Cf. coriaceous.

parallel-veined. Having its veins parallel to one another, without major intersecting vascular bundles, e.g. the leaflets of all _Cycas_species.

parasiticus. Latin, meaning �parasitic�, e.g. the root word of the second part of the specific epithet of Zamia pseudoparasitica, with the modifier pseudo (meaning �false�), referring to its epiphytic (not parasitic) habit and habitat.

parastichy. Spiral arrangement of leaves on an axis (or sporophylls in a cone), e.g. Encephalartos, Lepidozamia, and Macrozamia cones show well-defined clockwise and anticlockwise parastichies. See also orthostichy.

parcus. Latin, meaning �sparing� or �frugal�, e.g. the root word of the first part of the specific epithet of Macrozamia parcifolia, though technically referring to leaves, this epithet actually refers to the fine, wispy leaflets. See also folius.

parenchyma. Thin-walled cells in storage tissues such as the cortex zone between the epidermis and vascular tissue, e.g. the starch-richstems of Stangeria eriopus and similar cycads.See also sclerenchyma.

paripinnate. Even-pinnate; of a leaf or leaflet where the rachis or rachilla does not terminate in a solitary pinna or pinnule, e.g. most cycad leaves. Cf. imparipinnate.

pauci. Latin, meaning �few�, e.g. the first part of the specific epithet of Encephalartos paucidentatus, referring to the relatively smooth leaflet margins. See also dentate.

peat moss. Partially decomposed sphagnum moss, often added to soil to increase moisture retention; medium of choice for the �baggie method� of cycad seed germination.

pectinate. Comb-like; with closely-spaced, narrow segments, e.g. the megasporophyll margins of Cycas pectinata.

pedicel. Supporting stalk of a flower or gymnosperm sporophyll. See also peduncle.

peduncle. Supporting stalk of an inflorescence or gymnosperm cone. See also pedicel.

pellucid. Transparent or translucent, e.g. the leaflets of Zamia disodon.

peltate. With a stalk positioned centrally on the surface of a lamina or sporophyll,e.g. most cycad bullae.

pendent, pendulous. Hanging downwards (abaxially), e.g. the female cones of many Dioon species, or the leaves of Zamia sandovalii.

persistent. Remaining attached; not falling off, e.g. the leaf bases of Ceratozamia.

petiolate. Having or resembling a petiole. Cf. sessile.

petiole. Stalk of a leaf; in a compound leaf, that part of the axis below the lowermost leaflets, pinnacanths, or spines. See alsorachis. Cf. petiolule.

petiolule. Stalk of a leaflet, that part of the axisbelow the leaflet blade, e.g. as in Zamia manicata. See also rachilla.

pilose. With soft hairs,e.g. theimmature leaves of Ceratozamia miqueliana. See also hirsute, lanate, pubescent, sericeous, tomentose. Cf. glabrous, nitidus.

pinna, plural pinnae. Primary division of a compound leaf; leaflet.

pinna-pinna (pp) angle. Angle on the upper (adaxial) side of a leaf between the planes in which the hypothetical long axes of the leaflets occur (_sensu_Grobbelaar, 2002).

pinna-rachis (pr) angle. Distal angle between the hypothetical longitudinal axis of a leaflet and the axis of the rachis in the vicinity of the leaflet (_sensu_Grobbelaar, 2002).

pinnacanth. Sharply-pointed structure intermediate between a leaflet and a spine, usually green and hence photosynthetic, e.g. as on the rachis of some species of Dioon, Encephalartos,and Macrozamia. See also prickle, tooth.

pinnate. Feather-shaped; typically a leaf with leaflets or pinnae on either side of a rachis, e.g. most cycad leaves. S_ee also_ bipinnate, multipinnate.

pinnule. Secondary division of a compound leaf. See also pinna.

pith. Soft, sponge-like, central cylinder of the stem, composed mainly of parenchyma.

plane. Flat; level; pertaining to leaflets lacking distinctly raised veins. Cf.corrugated, pleated, plicate.

plant press. Structure typically made of two ventilated frames 12� x 18� (30 x 45 cm), within which plant specimens are arranged between sheets of driers and ventilators, tightly strapped together with press straps, in preparation of being added to a collection or herbarium.

**_plantae exsiccatae_.**Latin, in reference to herbarium specimens. See also exsiccatum, holotype, type.

platys,platy-. Greek, meaning �broad�, e.g. the root word for the first part of the specific epithet of Macrozamia platyrachis, referring to the broad rachis.

platyspermic. Of seeds, flattened so as to be not radially symmetrical, e.g. Cycas seeds. See also actinomorphic, zygomorphic.Cf. radiospermic.

pleated. Of a leaf creased along its length, e.g. Zamia neurophyllidia. See also corrugated, plicate. Cf. plane.

plicate. Pleated or folded longitudinally like a fan; often used (perhaps incorrectly) to refer to the corrugated appearance of the adaxial leaflet surface in species such as Zamia skinneri. Cf. plane.

plumose. Feathery in a whorled appearance, e.g. the arrangement of leaflets on therachis in Ceratozamia norstogii.

podos. Greek, meaning �foot�, e.g. the root word of the second part of the specific epithet of Cycas pachypoda, referring to its distinctive broad trunk base. See also pachys.

pollen, pollen grain. Fine powdery material (microspores) shed from the microsporangia of seed plants; in cycads sometimes referred to as prepollen; microspores containing amale gametophyte (microgametophyte).

pollen cone/strobilus. Male cone; microsporangiate strobilus. Cf. seed cone.

pollinator. Organism responsible for the transfer of pollen from the pollen cone to the seed cone; members of various insect groups have coevolved as cycad pollinators.

prasinus. Latin, meaning �leek green�, e.g. the root word of the specific epithet of Zamia prasina, referring to the bright grass-green leaflets.

prickle. Small, sharp protuberance of epidermal origin, usually green, usually somewhat irregularly distributed, e.g. on the petioles of most Ceratozamia and Zamia species; pinnacanths in Encephalartos have also been called prickles, but they are not epidermal in origin. See also spine, tooth.

procumbent. Trailing or lying along the ground but not rooting; typically referring to stems,e.g. the trunks of large, old plants of Encephalartos equatorialis. See also decumbent, prostrate. Cf.erect.

proliferous. Bearingoffsets and other vegetative propagation structures.

prostrate. Trailing or lying along the ground but not rooting; typically referring to stems,e.g. the stems of old plants of Zamia poeppigiana. See alsodecumbent, procumbent. Cf. erect.

protuberant. Swelling outward; bulging, e.g. megasporophyll bullae.

proximal. Nearest tothe point of attachment of a structure; basal. Cf. distal.

pruinose. With surface covered by a waxy bloom, e.g. the leaflets of Cycas pruinosa and Ceratozamia zoquorum.See also glaucous. Cf. nitidus.

prune. To partially or completely remove leaves; refers to both the aesthetic removal of dead or dying (senescing) leaves, and the reduction in leaf area as a means of reducing transpiration stress during transplanting.

pseudo. Greek, meaning �false�, e.g. the first part of the specific epithet of_Zamia pseudoparasitica_, referring to its epiphytic (not parasitic) habit and habitat. See also Latin parasiticus.

pseudocone. Term used by some cycadologists to refer to the cluster of leaf-like megasporophylls in Cycas.

pteron. Latin, meaning �wing�, e.g. the root word of the first part of the specific epithet of Encephalartos pterogonus, referring to the distinctive wing-like and toothed appendages below the terminal facet of the microsporophylls.

puberulent, adj. puberulous. Covered with minute hairs or very fine down; finely pubescent, e.g. the exposed tip of the microsporophylls of_Cycas wadei_, and the male cone peduncles of Zamia poeppigiana. See also hirsute, lanate, pilose, sericeous,tomentose. Cf. glabrous, nitidus.

pubescent. Densely covered with fine short hairs, e.g. the cataphylls of Ceratozamia euryphyllidia. See also hirsute, lanate, pilose, sericeous,tomentose. Cf. glabrous,nitidus.

pungent. Terminating in a stiff, sharp point, e.g. Dioon mejiae leaflets and Macrozamia sporophylls.

pup. Colloquial, referring to a cycad sucker or offset; occasionally applied to suckers or offsetsseparated from a �mother� plant for the purpose of vegetative propagation.

purpureus. Latin, meaning �purple�, e.g. the root word of the specific epithet of_Zamia purpurea_, referring to the deep reddish-purple emerging leaves and immature female cones.

�pus. Greek, suffix meaning �footed�, e.g. the second part of the specific epithet of Stangeria eriopus, referring to the woolly leaf bases. See also erio-.

pygmaeus. Latin, meaning �pygmy� or �dwarf�, e.g. the root word of the specific epithet of Zamia pygmaea, referring to the small stature.

r(h)achilla, plural r(h)achillae. Diminutive of rachis;secondary axis; sometimes used in reference to the axis along which pinnules are attached in cycads having compound leaflets, e.g. Bowenia.

r(h)achis, plural r(h)achides, r(h)achises. That portion of the axis of a compound leaf where leaflets are attached and excluding the petiole.

radial symmetry. Symmetry along many longitudinal planes all passing through a central axis,e.g. the leaves of a flush.

**radiospermic.**Of seeds, radially symmetric, e.g. the seeds of all cycad genera except Cycas. See also actinomorphic, zygomorphic. Cf. platyspermic.

receptive. Pertaining to a female cone whose megasporophylls have separated (cracked) to allow pollinators to enter during pollination. Cf. dehiscent.

recurved. Bent or curving downward (abaxially), e.g. the leaf tips of Encephalartos longifolius. See also reflexed.Cf.incurved.

reduplicate. Folded with the �V� opened downward(abaxially), e.g. the leaflets of Encephalartos inopinus and the apical leaflets of Dioon rzedowskii. Cf. keeled, secund.

reflexed. Of leaves, bent downward and outward more than 90 degrees, e.g. the emerging leaves of some Dioon species. See also circinate, conduplicate. Cf. declinate,deflexed, inflexed.

revolute. With margins rolled downwards (abaxially), e.g. the leaflet margins of_Cycas revoluta_ and Encephalartos ghellinckii. Cf. involute.

rhomboid. Of a 3-dimensional structure shaped like an oblique-angled parallelogram having four equal sides (= rhombus); of sporophylls, diamond-shaped with equal sides, e.g. the bullae of Encephalartos concinnus.

ribbed, ridged. Bearing ridges or raised markings, e.g. the sclerotesta of Encephalartos transvenosus, and the trunks of Lepidozamia hopei.

rigid. Not flexible or pliant; stiff, e.g. the leaflets of Zamia furfuracea.

robusta. Latin, meaning �large� or �robust�, e.g. the specific epithet of Ceratozamia robusta, referring to its large, robust habit.

root. Usually underground portion of a plant that lacks buds, leaves, or nodes and serves as support, draws minerals and water from the surrounding soil, and sometimes stores food.

root ball. Cylindrical or conical mass of roots and soil on a plant being prepared for transplant.

root cap. Parenchymatous layer of cells produced by the root meristem and covering it with a protective layer.

root prune. To carefully cut the roots of a field- or garden-grown plant in preparation for transplanting.

root rot. Disease characterized by root decay, caused by various fungi; one of the primary causes of death in cultivated cycads.

rooted, rooted out (less commonly rooted pup or rooted sucker). Colloquial, referring to a sucker (or offset) previously removed from a �mother� plant for the purpose of vegetative propagation and now fully re-established and ready for sale or re-planting.

rostrate. With a beak, e.g. the microsporophylls of Encephalartos longifolius.

rosulate. Having leaves (or other parts) arranged in a rosette, e.g. pertaining to all cycads.

rufous. Reddish to reddish-brown, e.g. the tomentum on the cataphylls of Cycas ophiolitica and the female cones of Zamia furfuracea.

rugose. Deeply wrinkled, e.g. the dried sarcotesta of many mature Cycas seeds. Cf.nitidus.

rugulose. Finely wrinkled; a diminutive of rugose, e.g. the cataphylls of_Zamia sandovalii_ and the sclerotesta of Dioon mejiae. Cf. nitidus.

sagittal crest. Central projection of the abaxial face of a megasporophyll. Cf. lateral lobe, median lobe.

sagittal ridge. Line, sometimes more distinct than others, separating the lateral facets from each other in Encephalartos sporophyll bullae that lack amedian facet (Melville, 1957). Cf. latero-sagittal ridge,medio-lateral ridge.

sarcotesta. Fleshy outer layer of the integument of a cycad seed, brightly-colored in many cycad genera. Cf. sclerotesta.

**scabrous.**Rough to the touch, e.g. the abaxial surface of the leaflets of_Encephalartos latifrons_. Cf. nitidus.

scarification. Any process of penetrating the protective seed coat of dormant seeds accomplished by chemical, mechanical, heat, or moisture treatment allowing water and oxygen into the seed, thereby helping to improve germination.

scarious. Thin, membranous, and dry, e.g. the leaf bases of Macrozamia pauli-guilielmi and the cataphylls of Zamia sandovalii.

sclerenchyma. Mechanical (supportive) tissue composed of empty, thick-walled cells. See also parenchyma.

sclerotesta. Hardor stony inner layer of the integument of a cycad seed. See also stony coat. Cf. sarcotesta.

scurfy. Covered with small papery scales, e.g. the female cone peduncles of Ceratozamia fuscoviridis. See also furfuraceous.

secund. Having leaflets at a markedly elevated angle above the rachis, yielding a V-shaped leaflet angle in cross section, e.g. the leaflets of Macrozamia secunda or Encephlartos eugene-maraisii. See also keeled.Cf. reduplicate.

seed. Fully mature ovuleafter fertilization, with an embryo, storage tissue, and all integuments**.** See also omnule, corruptule.

seed cone. Female cone;ovulate cone; megasporangiate strobilus. Cf. pollen cone.

seedling. Non-reproductive life cycle stage with no visible stem and one to few leaves not arranged in a crown (sensu Y��ez-Espinosa, 2009). Cf. adult, juvenile, mature.

segmented. Of a leaf or other like organ that is divided into distinct segments,e.g. the finely dichotomously branching marginal spines of the megasporophyll lamina of Cycas segmentifida.

seminal fringe. Line of demarcation separating the sporophyll face from the point of attachment of the ovule on the adaxial face. Cf. seminal ridge.

seminal ridge. Line of demarcation separating the sporophyll face from the point of attachment of the ovule on the abaxial face. Cf. seminal fringe.

semiterete. Half-round in cross section, e.g. the petiole of Encephalartos arenarius.Cf. terete.

senticosus. Latin, meaning �full of thorns�, e.g. the specific epithet of Encephalartos senticosus, incorrectly referring to its spiny leaflet margins, which are actually serrations.

sericeous. With fine hairs giving a silky texture, e.g. the cataphylls of Cycas diannanensis or the emerging leaves of Zamia hamannii. See also hirsute, lanate, pilose, pubescent, tomentose.Cf. glabrous, nitidus.

serpentine. Of shape, sinuous or snake-like, e.g. the trunks of large, old plants of Dioon merolae; of a substrate, containing magnesium silicate and usually dull green, e.g. the soil where _Macrozamia serpentina_grows.

serrate. With a margin of saw-toothed, sharply-tipped protrusions pointing apically, e.g. the leaflet margins of Zamia skinneri. See also dentate, tooth.

serrulate. Minutely serrate, e.g. the leaflet margins of Bowenia serrulata. See also denticulate.

sessile. Without any apparent stalk, e.g. the male cones of Dioon mejiae and Encephalartos lebomboensis; in reference to cycad leaves without petioles, e.g. as in Dioon spinulosum and Encephalartos villosus.

sexual dimorphism. Marked phenotypic differences between males and females of the same species, e.g. the differences in shape and structure of the male and female cones of most cycad species. See also dimorphic.

shield. In cycads, the broadly flattened terminal facet of a cycad megasporophyll.See also bulla.

shielding (s) angle. Angle by which a leaflet is transversely inserted on the rachis, often, but not always, resulting in leaflet overlap (sensu Grobbelaar, 2002), e.g. if leaflets overlap incubously the s-angle is nominally positive, if leaflets overlap succubously the s-angle is nominally negative.

short-stalked. Colloquial, pertaining to a short peduncle; sessile. Cf. long-stalked.

sigmoid. S-shaped, _e.g._the peduncle of some cycadcones.

simplici-. Latin, compound prefix meaning �simple�, e.g. the first part of the specific epithet of Cycas simplicipinna, in reference to its relatively simple leaflets compared to those of C. micholitzii.

sinuate, adj. sinuous. Having a strongly waved margin, e.g. the leaflets of Cycas diannanensis. Cf. flat.

solitary. Of a plant with a single stem producing no suckers or offsets, or a plant producing a single cone. Cf. clumping, suckering.

spatulate. Shaped like a spatula, e.g. the megasporophylls of Cycas micronesica.

specimen. Specific plant strategically placed so people can gain the greatest enjoyment for the color, texture, or other pleasures it provides. See also herbarium specimen.

spectabilis. Latin, meaning �visually striking� or �remarkable�, e.g. the specific epithet of Bowenia spectabilis, in reference to its unusual, striking leaves.

spheroid. Shaped like a sphere but not perfectly round; ellipsoid, e.g. some Cycasseeds and the microsporangia of many cycad species.

spine. Hard, sharp, non-photosynthetic protuberance with vascular connections and not of epidermal origin; the spines on many cycad rachises and sporophylls are actually reduced leaflets. See also pinnacanth,prickle, tooth.

spinescent, spinose. Terminating in asharp point; bearing sharp points, e.g. the leaflets and petioles of many cycadspecies. See also pungent. Cf. entire, inerm, unarmed.

spiralis. Latin, meaning �spiraled�, e.g. the specific epithet of Macrozamia spiralis, referring to the (sometimes) twisted rachis.

splendens. Latin, meaning �shining� or �brilliant�, e.g. the specific epithet of Zamia splendens, referring to the striking (and shiny) appearance of the leaflets.

spongy endocarp. Tissue layer of the sarcotesta of some Cycas seeds that makes them naturally buoyant, e.g. as in Cycas mironesica. See also flotation layer.

spreading. Extending out over a wide area; expansive, not upright; in cycads, used to describe the natural orientation (or habit) of the most recent crown or flush of leaves, e.g. the crown of _Ceratozamia latifolia_or Dioon tomasellii. Cf. arching, ascending, erect.

sprout. Colloquial for a germinated seed.

**staminate cone/strobilus.**Incorrectly-derived term for male cone; pollen cone; microsporangiate strobilus.

stem. The main axis, or a branch of the main axial system, of a plant; caudex in cycads.

stem borer. Insect larva that tunnels into stems and trunks, e.g. the native beetle Dihammus marianarum (Coleoptera: Cerambycidae) that infests Cycas micronesica in Guam.

stenos. Greek, meaning �narrow�, e.g. the root word of the first part of the specific epithet of Macrozamia stenomera, referring to the finely divided leaflets. See also �merus.

sterile. In cycads, that part of a cone or megasporophyll lacking functional sexual parts; infertile. Cf. fertile.

sterile tip. Apex of many cycad cones lacking fertile sporophylls.

stipe. Small stalk, _e.g.thin tissue that connects the ovules to the sporophylls in_Dioon female cones. See also funiculus.

stipulate. Having an appendage (stipule) at the base of a petiole or cataphyll,e.g. in_Stangeria_, a hood-like stipule subtends each leaf base.

stony coat. Colloquial for sclerotesta.

striate. With longitudinal lines, grooves, or ridges,e.g. the abaxial surface of the leaflets of Encephalartos paucidentatus.

strobilus, plural strobili. Reproductive structure of gymnosperms and some cryptogams such as Selaginella; organized collection of sporophylls on a central axis. See also cone, megasporangiate strobilus, microsporangiate strobilus.

subulate. Narrow and drawn out to a fine point; awl-shaped, e.g. the megasporophyll lobes of Cycas multipinnata.

succession. The act or process of following in order or sequence; in cycads, pertaining to the manner of production of cones as a diagnostic trait in certain species groups within Encephalartos (sensu Vorster, 2004).

succubous. Arrangement in which a leaflet partially shields the one below (the next proximal leaflet) when viewed from above (adaxially), e.g. as in Encephalartos turneri. Cf. incubous.

sucker. Vegetative axisarising from an adventitious bud at the base of a cycad trunk; colloquial, pup. Cf. offset.

suckering. Vegetative production of suckers; habit of such a plant, often forming a clump; colloquial, pupping. Cf. solitary.

sulcate. Havinga longitudinal groove or furrow, e.g. the abaxial midvein of Cycas multipinnata leaflets; cycad pollen grains are characteristically monosulcate.

surculose. Producing suckers; suckering.

suspensor. That part of the plant embryo that attaches the embryo to the supporting tissues of the developing seed.

suture. Line of opening ordehiscence of a closed structure, e.g. as in cycad microsporangia.

taproot. Enlarged or deeply descending storage root derived from the primary root of an embryo; main root of a plant, having a single, dominant axis and often serving the functions of structural support and food storage, e.g. the extensive taproot of some plants of Zamia pseudoparasitica that grow from the plant perched on high tree branches all the way to the forest floor. Cf. feeder root.

tegula. Latin, meaning �tile�, e.g. the root word of the first part of the specific epithet of Encephalartos tegulaneus, referring to its overlapping microsporophylls that resemble roof tiles.

terete. Solid structure which is circular in cross section; cylindrical or nearly so, _e.g._the petioles of most cycad species. Cf. semiterete.

terminal. Arising from or positioned at the tip, e.g. used in reference to the most distal leaflets on a cycad leaf; apical. See also terminal facet. Cf. basal, median.

terminal facet. Flat surface on the apex of sporophylls that have raised bullae (Melville, 1957). Cf. lateral facet, median facet.

tiusinte. Vernacular name of Dioon mejiae by the indigenous people in Olancho, Honduras, who use the seeds to make a variety of foodstuffs (Bonta et al., 2006).

tomentose. Densely woolly in a finely matted fashion, e.g. the female cones of_Dioon_. See also hirsute, lanate, pilose, pubescent, sericeous. Cf. glabrous, nitidus.

tomentum. Covering of fine hairs. See also indumentum, tomentose.

tooth. Sharply-tipped protrusion along a leaf or leaflet (or analogous structure) margin pointing away at an angle of 90�. See also serrate,dentate, spinose.

transparent. Of veins that readily transmit light when held up to a light source, _e.g._of the leaflets of Ceratozamia zoquorum. Cf. opaque.

transplant. To relocate a plant from one location (or one container) to another; a plant that has been so relocated.

�tree dioon�. Any of the large, arborescent species of Dioon, e.g. Dioon mejiae.

triangular. Of a 3-dimensional structure that is three-sided, e.g. the petiole of Cycas rumphii. Cf. quadrangular.

trifurcate. With threeterminal, long lobes, e.g. the apices of some Encephalartos hildebrandtii leaflets. Cf. bifurcate.

tripinnate. Thrice pinnately compound. Cf. bipinnate, once-pinnate, twice-pinnate.

tropos. Greek, meaning �boat keel�, e.g. the root word of the first part of the specific epithet of Cycas tropophylla, referring to its distinctively keeled leaves. See also phyllon.

trullate. Of a 2-dimensional structure resembling a trowel blade, i.e. with four straight sides with the axis broadest below the middle and a length:breadth ratio between 3:2 and 2:1, e.g. the leaflets of_Zamia vazquezii_.Cf. obtrullate.

truncate. With an abrupt ending, as though cut off terminally,e.g. the leaves of Encephalartos inopinus and Microcycas calocoma, or the megasporophylls of Zamia.

trunk. Main woody axis of a tree; colloquially, in reference to the caudex orstem of arborescent cycads.

trunkless. Without a trunk; acaulescent. Cf. arborescent.

tuber, tuberous. Thickened underground stem.

tuberculate. Covered with small raised protuberances, e.g. the bulla surface of some cycad megasporophylls. See also verrucose.

twice-pinnate. Doubly compound; having second-order pinnae or pinnae in turn made up of pinnules; bipinnate. Cf. once-pinnate, tripinnate.

type (T.). Herbarium specimen or other element (e.g. illustration) to which the name of a taxon is permanently attached, whether as a correct name or a synonym; the type is not necessarily the most typical or representative element of a taxon. See also holotype.

unarmed. Lacking spines or prickles; inerm, e.g. the petioles of Zamia inermis. Cf. armed.

umbinate. Having or resembling a knob or knob-like protuberance (umbo), e.g. the microsporophyll faces of Cycas micronesica.

unbranched. Possessing no lateral branches; solitary, e.g. the caudex of most arborescent cycads. Cf. branched.

uncinate. Hooked at the apex, e.g. the microsporophylls of Encephalartos barteri.

undulate. With wavy margins, usually of leaflets, e.g. the leaflets of Cycas apoa. Cf. flat.

variegated. Having two or more colors in a blotched or mottled pattern, e.g. the leaflets of Zamia variegata.

vein. Strand of vascular tissue.

verrucose. Warty in appearance, e.g. the bulla surface of many cycad sporophylls, or the seeds of Cycas diannanensis. See also tuberculate.

verticilate. Arranged in whorls; fasciculate, e.g. the leaflets of the common form of Ceratozamia hildae.

villous. With long, soft hairs, e.g. the petioles of Encephalartos villosus.

**_viridis_.**Latin, meaning �green�, _e.g._the specific epithet of Macrozamia viridis, in reference to its bright green leaflets.

vivipary. Phenomenon by which seeds begin to germinate prior to dehiscence of the female cone, e.g. as often happens in Zamia pseudoparasitica and sometimes happens in Cycas micronesica.

warty. Covered in bumps; verrucose, e.g. the female cones of Encephalartos msinganus.

weevil. Any of the numerous beetles of the Family Curculionidae; many are pollinators of cycads.

wet pollination. Type of hand pollination whereby the pollen is introduced to the female cone in liquid form, often by means of pouring or squirting into the open spaces (cracks) between sporophylls.

whorl. Ring-like arrangement of similar parts arising from a common point or node. See also cohort, flush.

wing, adj.winged. In cycads, a thin appendage of tissue below the terminal facet of the microsporophylls of Encephalartos pterogonus.See also alate.

wool. Colloquial for heavy tomentum on some cycad caudices, e.g. Encephalartos friderici-guilielmi.

xiphos. Greek, meaning �sword�, e.g. the root word of the first part of the specific epithet of Cycas xipholepis, referring to the long, hard,pungent cataphylls.

zamia borer. Insect that bores into hypogeous Zamia stems. See also stem borer.

zygomorphic. Of a bilaterally symmetric structure that can be halved only in one plane to give two halves that are mirror images of each other; of seeds, platyspermic. Cf. actinomorphic.

ACKNOWLEDGMENTS

The following individuals graciously provided photos to illustrate some of the terms: Mark Bonta, Ramiro Chaves, Jeff Chemnick, Kurt Eising, Douglas Goode, Tim Gregory, Arnold Greyling, Nat Grobbelaar, Greg Holzman, Eddie Hsieh, Bruce Ironmonger, Anders Lindstr�m, Phan Ke Loc, Tommy Marler, Roy Osborne, Tobias Spanner, Geoff Stein, Loran Whitelock, and the U.S. Botanical Garden. The following websites were also used as sources for a few of the photos: The Cycad Pages, Cycad Society of South Africa, and Jungle Music.

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