‘Synonym’: a name rejected because of different taxonomic interpretation, or under the rules of nomenclature.
‘Synonym’: a name rejected because of different taxonomic interpretation, or under the rules of nomenclature.
‘Arborescent’: perennial, attaining more or less treelike aspect without exhibiting all the ‘tree’ characteristics.
‘Shrub’: a woody, branching perennial with persistent above-ground parts, of smaller stature than a tree and without a well expressed trunk.
‘Subshrub’: an under-shrub, or small shrub which may have partially herbaceous stems.
‘Liana’ or ‘liane’: a woody climber.
‘Herb’: a plant without persistent above-ground stems.
‘Cladode’: a phylloclade of one internode.
‘Phyllode’: a flat, dilated petiole fulfilling the functions of a leaf.
‘Phylloclade’: a stem modified to function as a leaf or leaves.
‘Biennial’: a plant requiring two years to complete its life-cycle, growing vegetatively in the first, then flowering, fruiting and perishing in the second.
‘Perennial’: a plant which persists and continues growth for several to many years.
‘Corm’: bulblike, fleshy, rooted stem or stem base, associated with vegetative reproduction/perennation.
‘Rhizome’: perennial, prostrate or oblique, more or less subterranean, more or less dorsiventral stem, producing roots below and leaves and/or stems apically or above and apically.
‘Tuber’: a thick, short, swollen vegetative part concerned with food storage (may represent either root or stem).
Unsatisfactory character state definitions, which in practice are not properly exclusive. ‘Tuberous or not’ and specification of kinds of tubers await resolving into separate characters.
Clockwise (viewed from above and/or as the stem approaches you) = ‘ascending a vertical support from right to left when viewed from the side’ = Darwin’s ‘following the sun’. ‘Dextrorotatory’ = anticlockwise.
‘Leptocaul’ (= leptocladous): twiggy, with abundant, relatively slender branches.
‘Helophytes’: marsh plants.
‘Mesophytes’: plants avoiding extremes of moisture and drought — in habitats intermediate between those of hydrophytes and xerophytes.
‘Xerophytes’: plants which normally subsist in habitats affording relatively little moisture. Usually exhibiting one or more recognisable ‘xeromorphic’ features, which include extreme hairiness; thick cuticles; harsh, pungent or rolled leaves with much sclerenchyma; spines, prickles and switch-plant properties (q.v.); succulence.
‘Deciduous’ implies seasonally synchronized leaf fall resulting in a leafless condition in winter, and the leaves are usually non-leathery.
‘Evergreens’ are leafy all year round, and the leaves are often more or less leathery.
‘Alternate’: the leaves neither manifestly ‘opposite’ nor genuinely whorled. A loose term in widespread taxonomic usage, reflecting failure to describe phyllotaxy more precisely. Implies ‘spiral or distichous’.
‘Whorled’: the leaves (or structures reasonably interpretable as such) disposed in rings of three or more per node.
‘Distichous’: borne in two longitudinal ranks, these on opposite sides of the axis.
‘Tristichous’: borne in three longitudinal ranks.
‘Perfoliate’: when the stem appears to pass through the blade of the leaf.
‘Stipulate’: having stipules, or structures recognizable as modifications (spines, glands etc.), fusion products or vestiges of them.
Stipules have protective (sometimes including secretory) functions during shoot and leaf development. They are commonly associated with trilacunar nodes, deriving their vascular supply via branches from the lateral leaf traces. In mature material, stipules even when adnate to the petiole are frequently readily recognisable as such (and distinguishable from mere winging of the petiole) through possessing separate vascular supplies, different textures, or abscission zones distinct from those of the associated leaves. However, small stipules often abscise early, so that detecting their ‘presence’ in mature material often depends on recogning their scars. Furthermore, is sometimes hard to distinguish stipules from leaflets or leaf sheaths, or even in some families (notably Rubiaceae) from leaves; and interpretive problems are posed by other structures (e.g. glands) which may or may not be legitimately considered stipular. Convincing solutions to questionable cases require detailed comparative studies, and are inaccessible for routine identifications.
The present compilation no doubt contains errors reflecting failure to distinguish ‘absent’ from ‘caducous’. These can be corrected as they come to light. Meanwhile, ‘presence or absence of stipules’ is a perfectly good character in the context of INTKEY identifications, provided intelligent use is made of the TOLERANCE facility.
‘Caducous’: falling off early.
‘Involute’: curled, rolled or bent inwards, to enclose or partially enclose (part of) the inner (adaxial) surface.
Leaf
‘Isobilateral’: capable of being divided into two similar halves; i.e., more or less flattened (adaxially/abaxially, or laterally), without noticeable adaxial/ abaxial or lateral anatomical distinction. Perhaps a new term, ‘isobifacial’, should be introduced.
‘Centric’: with more or less radial anatomical organization.
The leaves characteristic of many Monocots which are sometimes described as ‘unifacial’ here fall under ‘isobilateral’ or ‘centric’, according to the extent of flattening.
‘Raphides’: slender, needle-shaped calcium oxalate crystals, arranged parallel to each other in tight bundles, the bundles enclosed in raphide sacs. Unorientated acicular crystals are excluded by this definition.
Information mainly from Metcalfe and Chalk (1950), Carlquist (1988). Data on this character are unreliable through lack of direct information on families observed to exhibit ‘negatives’. When unmentioned in anatomical family descriptions, it has perforce been treated as implicitly exhibiting the negative state. Families undescribed or poorly known anatomically have been tagged as ‘unknown’.
See comments under ‘tracheids’.
However, the preceding characters (sexuality of individual flowers, presence on specimens of unisexual flowers) have been compiled from this one, for easier and more reliable use in identificatory connections.
‘Disk’: an elevated or appendicular, usually more or less fleshy and nectariferous development on the receptacle internal to the perianth or stamens, which may be receptacular or staminodial (or ambiguous) in origin.
‘Gynoecium’: a collective term for the total female component of the flower, including all recognisable derivatives of this.
‘Androecium’: the total male component of the flower, including all recognisable ‘derivatives’ of this. ‘Androecial members’ thus include the stamens (q.v.), plus any staminodial structures (q.v.).
This unsatisfactory character will eventually be subsumed into the nearby text character (infloresences — type). The terms in everyday use employed here have adequate definitions for practical application and for resolution into a hierarchy of multistate characters, but their haphazard application in published descriptions (in which, for example, different levels of aggregation are seldom mentioned) precludes effectively using them in that fashion without organizing the data de novo.
See the text character for definitions of terms
The following terms have been employed here. They have adequate definitions for practical application and for resolution into a hierarchy of multistate characters, but their haphazard application in published descriptions (in which, for example, different levels of aggregation are seldom mentioned) precludes effectively using them in that fashion without organizing the data de novo.
‘Catkin’ (ament): a scaly-bracted, deciduous, often pendulous or flexuous raceme or (more usually) raceme of cymules, with reduced (anemophilous), apetalous, usually unisexual flowers.
‘Corymb’: a relatively broad and short-internoded, flat-topped or convex, open, indeterminate (centripetal) inflorescence, whose outer flowers open first.
‘Cyme’: a determinate flower cluster, with central flowers opening first.
‘Fascicle’: a loose term for a condensed or close cluster, of whatever detailed construction (unresolved/unresolvable into racemose/cymose).
‘Glomerule’: a cluster of dense or compact, short-pedicelled or short-peduncled clusters or heads, with a common involucre.
‘Panicle’: an indeterminate (racemose, corymbose), compound inflorescence (the primary branches racemose, the nature of lower order branching unspecified).
‘Raceme’: a simple, elongate-internoded, indeterminate (centripetal) inflorescence with pedicelled flowers which open acropetally.
‘Thyrse’: a mixed (compound) inflorescence, in the form of a contracted or ovate panicle, the primary branching racemose (indeterminate) but the ultimate branching cymose (determinate).
‘Umbel’: A relatively broad, often flat-topped, indeterminate (centripetal) inflorescence, whose pedicels or peduncles arise from a common point and whose outer flowers open first.
‘Verticil’: a whorl of flowers about an axis (of whatever detailed organization).
‘Pseudo-papilionaceous’: denotes a floral structure superficially resembling the corolla of Leguminosae-Papilionoideae, but morphologically different.
Note that the ‘floral tube’ (hypanthium) of Dicots is generally thought not to be homologous with the ‘perigone tube’ of Monocots, which is usually more obviously perianthial in appearance and texture.
‘Corolla’: the inner component of the floral envelope, represented by petals or equivalent structures.
‘Perianth’: floral envelope(s), inclusive of calyx, corolla, tepals and all morphologically equivalent structures.
‘Tepal’: a segment or unit of a whorled perianth which is not resolvable into calyx and corolla.
In general, an effort has been made to encode this character straightforwardly, according to appearance when conscientiously examined by a trained botanist using a dissecting microscope. However, alternative interpretations of it (and of its dependents) have been encoded in the descriptions where this seemed appropriate. If in doubt about its use in identification with INTKEY, entering all the reasonable possibilities will usually still afford useful discrimination.
An attempt has been made on principle to encode family morphological descriptions so as to allow for likely alternative interpretations or ‘misinterpretations’. The same device has been used in families where the ‘true’ state of affairs seems sometimes to be deducible only from comparative morphology. Its implementation has necessarily been somewhat selective, however, in view of the complications arising from character dependencies.
The DELTA system currently has no device for encoding/interpreting the loose botanical convention ‘many’ (= ‘too many to bother counting’), application of which varies from character to character and from person to person. In compiling the descriptions, ‘many’ has been interpreted so as to encompass the number specified in the character list. The actual ranges entered usually represent guesswork, and are not reliable.
The reliability of the Monocot data is very uncertain: ‘3+3’ in published descriptions has been assumed to imply two tangible whorls, rather than extrapolation from phylogenetic assumptions.
The DELTA system currently has no device for encoding/interpreting the loose botanical convention ‘many’ (= ‘too many to bother counting’), application of which varies from character to character and from person to person. In compiling the descriptions, ‘many’ has been interpreted so as to encompass the number specified in the character list. The actual ranges entered usually represent guesswork, and are not reliable.
‘Partially gamosepalous’: two or more calyx members joined (palpably, or readily interpreted as such with reference to lobes, venation and considerations of floral symmetry), the other(s) free.
‘Gamosepalous’ (monosepalous): reasonably interpretable as representing joining of all the calyx members into a single structure (as evidenced by free lobes, venation and considerations of floral symmetry). Nearly always associated with possession of a long or short calyx tube.
In the present descriptions, any tubular structure bearing corolla and/or stamens in addition to calyx ‘lobes’ is regarded as hypanthium (q.v.), not calyx tube. Calyx ‘lobes’ inserted on such a hypanthium at or below the level of insertion of the (uppermost cycle of) stamens are treated as free sepals, and the calyx is fairly unambiguously ‘polysepalous’. Likewise, calyx ‘lobes’ inserted directly on an inferior ovary (i.e. with no free tube) also represent polysepaly. Ambiguities arise when a free perianth tube is continued without textural change (etc.) above the level of insertion of stamens, so that it is hard to decide where ‘hypanthium’ ends and ‘calyx’ begins: an effort has been made in the descriptions to allow for alternative interpretations.
‘Imbricate’: where the edges of the sepals or calyx lobes overlap in the flower bud, with one or more members wholly external, one or more wholly internal and the other(s) with one side overlapped and the other overlapping.
‘Contorted’ (convolute, twisted): where the edges of the sepals or calyx lobes overlap in the flower bud in regular sequence, with each member having one edge overlapped and the other overlapping.
‘Valvate’: where the edges of the sepals or calyx lobes are contiguous in the flower bud without overlapping.
‘Induplicate-valvate’: where the edges of the sepals or calyx lobes in the flower bud are bent inwards along their length, and applied valvately to those of their neighbours.
‘Open’: where the edges of the sepals or calyx lobes are neither overlapping nor contiguous with one another in the flower bud.
‘Plicate’: where the sepals or calyx lobes are folded, fanlike, in the flower bud. (It remains to be established whether this condition is exclusive, or represents a qualification of one of the others.)
Precisely defined variants of ‘imbricate’ (quincuncial, cochlear), and left versus right handed orientation of these and of ‘contorted’, are potentially taxonomically informative, but are largely undocumented.
‘Posterior’: adaxial, = on the side against the axis on which the flower is borne.
Use with caution, since the ‘morphological’ orientation (encoded here) is sometimes different from the apparent orientation because of twisting (resupination) of the pedicel, e.g. in many orchids.
The DELTA system currently has no device for encoding/interpreting the loose botanical convention ‘many’ (= ‘too many to bother counting’), application of which varies from character to character and from person to person. In compiling the descriptions, ‘many’ has been interpreted so as to encompass the number specified in the character list. The actual ranges entered usually represent guesswork, and are not reliable.
‘Partially gamopetalous’: two or more corolla members joined (palpably, or readily interpreted as such with reference to lobes, venation and considerations of floral symmetry), the other(s) free.
‘Gamopetalous’ (monopetalous): reasonably interpretable as representing joining of all the corolla members into a single structure (as evidenced by free lobes, venation and considerations of floral symmetry). Nearly always associated with possession of a long or short corolla tube.
‘Contorted’ (convolute, twisted): where the edges of the petals or corolla lobes overlap in the flower bud in regular sequence, with each member having one edge overlapped and the other overlapping.
‘Valvate’: where the edges of the petals or corolla lobes are contiguous in the flower bud without overlapping.
‘Induplicate-valvate’: where the edges of the petals or corolla lobes in the flower bud are bent inwards along their length, and applied valvately to those of their neighbours.
‘Open’: where the edges of the petals or corolla lobes are neither overlapping nor contiguous with one another in the flower bud.
‘Plicate’: where the petals or corolla lobes are folded, fanlike, in the flower bud.
Precisely defined variants of ‘imbricate’ (quincuncial, cochlear), and left versus right handed orientation of these and of ‘contorted’, are potentially taxonomically informative (e.g. Scotland et al. 1994 for Acanthaceae and relatives) but are undocumented for most families.
It remains to be established whether ‘plicate’ and ‘crumpled’ represent exclusive states, or qualifications of the others (as seems likely).
The DELTA system currently has no device for encoding/interpreting the loose botanical convention ‘many’ (= ‘too many to bother counting’), application of which varies from character to character and from person to person. In compiling the descriptions, ‘many’ has been interpreted so as to encompass the number specified in the character list. The actual ranges entered usually represent guesswork, and are not reliable.
‘Androecium’: the total male component of the flower, including all recognisable ‘derivatives’ of this. ‘Androecial members’ thus include the stamens (q.v.), plus any staminodial structures (q.v.).
The reliability of the data is very uncertain, especially for Monocots: e.g., ‘3+3’ in published descriptions has been assumed to mean two detectable whorls, rather than extrapolation from phylogenetic theory.
‘Androecium’: the total male component of the flower, including all recognisable ‘derivatives’ of this. ‘Androecial members’ thus include the stamens (q.v.), plus any staminodial structures (q.v.).
‘Staminode’: a sterile stamen, or a modified structure identifiable as such, borne in the androecial region of the flower. May be merely ‘imperfect’, vestigial, or specialized (e.g. petaloid or nectariferous).
The DELTA system currently has no device for encoding/interpreting the loose botanical convention ‘many’ (= ‘too many to bother counting’), application of which varies from character to character and from person to person. In compiling the descriptions, ‘many’ has been interpreted so as to encompass the number specified in the character list. The actual ranges entered usually represent guesswork, and are not reliable.
‘Staminode’: a sterile stamen, or a modified structure identifiable as such, borne in the androecial region of the flower. May be merely ‘imperfect’, vestigial, or specialized (e.g. petaloid or nectariferous).
‘Didynamous’: stamens paired, with two long and two short (as in most Labiatae).
‘Tetradynamous’: stamens four long and two short, as in Cruciferae.
Forms theoretically exhibiting vestigial opercula (in the form of coarse granules, exine fragments) have been encoded as inoperculate, with qualifying comment. The correct treatment would employ three ordered states (operculate/with vestigial operculum/inoperculate, without vestiges), but observations permitting reliable assignment may be unavailable for most of the 25 or so ‘ulcerate’ families.
Recorded here only for families supposedly closest to Gramineae (see Linder and Ferguson 1985, Kellogg and Campbell 1987).
Recorded here only for families supposedly closest to Gramineae (see Linder and Ferguson 1985, Kellogg and Campbell 1987). A list of families with ‘at least one representative exhibiting columellae (bacules)’ could be drawn up from the usual compilations (notably from Erdtman 1966), but it would be useless in the absence of data on alternative intertitial types.
‘Carpel’: the ovule-bearing unit of the gynoecium (including any associated style and stigma), representing a hypothetical ancestral ‘megasporophyll’ (a fertile, three-veined leaf with ovules near its edges associated with the lateral veins). Easily recognisable in practice when the gynoecium is ‘monomerous’ or ‘apocarpous’ (i.e. when the carpels are solitary, or multiple but separate), but becoming increasingly theoretical with increasing degrees of (hypothetical) congenital fusion in ‘syncarpous’ (compound) gynoecia. Thus, where the ovary is unilocular the ‘number of carpels’ represents phylogenetic speculation based on the lobing of the ovary, vestigial features, the number of styles or stigmas, the placentation pattern, the vasculature, the symmetry of the flower, etc.
The DELTA system currently has no device for encoding/interpreting the loose botanical convention ‘many’ (= ‘too many to bother counting’), application of which varies from character to character and from person to person. In compiling the descriptions, ‘many’ has been interpreted so as to encompass the number specified in the character list. The actual ranges entered usually represent guesswork, and are not reliable.
An attempt has been made on principle to encode family morphological descriptions so as to allow for likely alternative interpretations or ‘misinterpretations’. The same device has been used in families where the ‘true’ state of affairs seems sometimes to be deducible only from comparative morphology. Its implementation has necessarily been somewhat selective, however, in view of the complications arising from character dependencies.
‘Carpel’: the ovule-bearing unit of the gynoecium (including any associated style and stigma), representing a hypothetical ancestral ‘megasporophyll’ (a fertile, three-veined leaf with ovules near its edges associated with the lateral veins). Easily recognisable in practice when the gynoecium is ‘monomerous’ or ‘apocarpous’ (i.e. when the carpels are solitary, or multiple but separate), but becoming increasingly theoretical with increasing degrees of (hypothetical) congenital fusion in ‘syncarpous’ (compound) gynoecia. Thus, where the ovary is unilocular the ‘number of carpels’ represents phylogenetic speculation based on the lobing of the ovary, vestigial features, the number of styles or stigmas, the placentation pattern, the vasculature, the symmetry of the flower, etc.
With few exceptions (e.g. Hernandiaceae), inferior unilocular ovaries seem reasonably interpretable as pseudomonomerous and syncarpous (q.v.), and have been treated as such in the descriptions.
‘Apocarpous’: of a gynoecium composed of two or more separate carpels.
‘Monomerous’: of a gynoecium consisting of a solitary carpel.
‘Semicarpous’: of a gynoecium of two or more carpels, whose ovaries are only partially (basally) joined.
‘Syncarpous’: of a gynoecium composed of two or more (theoretically) congenitally united carpels.
‘Pseudomonomerous’ (a term often appearing as data comment in the present descriptions): of an ostensibly monomerous gynoecium, which is supposed on comparative morphological grounds (etc.) to represent a reduced syncarpous one. An effort has been made to encode the monomeric alternative and its dependent characters, at least as an alternative, for all families exhibiting ‘pseudomonomery’ deducible only from comparative morphology. All inferior unilocular ovaries seem reasonably interpretable as pseudomonomerous and syncarpous (q.v.), and have been treated as such in the descriptions. (See ‘carpel’ for further information.)
An attempt has been made on principle to encode family morphological descriptions so as to allow for likely alternative interpretations or ‘misinterpretations’. The same device has been used in families where the ‘true’ state of affairs seems sometimes to be deducible only from comparative morphology. Its implementation has necessarily been somewhat selective, however, in view of the complications arising from character dependencies.
The DELTA system currently has no device for encoding/interpreting the loose botanical convention ‘many’ (= ‘too many to bother counting’), application of which varies from character to character and from person to person. In compiling the descriptions, ‘many’ has been interpreted so as to encompass the number specified in the character list. The actual ranges entered usually represent guesswork, and are not reliable.
‘Posterior’: adaxial, = on the side against the axis on which the flower is borne.
The DELTA system currently has no device for encoding/interpreting the loose botanical convention ‘many’ (= ‘too many to bother counting’), application of which varies from character to character and from person to person. In compiling the descriptions, ‘many’ has been interpreted so as to encompass the number specified in the character list. The actual ranges entered usually represent guesswork, and are not reliable.
‘Pendulous’ (descending): (ovule) fixed to an axile, free central, apical or parietal placenta, with the its top hanging or turned towards the base of the ovary.
‘Horizontal’: (ovule) fixed to an axile, free central or parietal placenta, with its axis more or less at right angles to that of the ovary.
‘Ascending’: (ovule) fixed to a basal, axile, free central or parietal placenta, with its top facing or turned towards the distal end of the ovary.
See Geesink et al. (1981) for diagrams.
‘Epitropous’: the raphe dorsal when the ovule is ascending, ventral when it is descending. The latter case is equivalent to ‘micropyle upwards and outwards’ in older literature; but ‘micropyle superior’ does not distinguish apotropous from epitropous. (See Geesink et al. (1981) for excellent diagrams.)
This nineteenth century character is largely ignored in modern accounts. It implies the existence of a taxonomically important distinction among non-orthotropous ovules, between those seeming to represent a phylogenetic rotation and adhesion to its funicle of the ancestral orthotropous ovule ‘upwards and inwards’, i.e. with the micropylar end rotating towards the distal end of the ovary (ovule involute; epitropous), and those where it appears to have rotated and adhered ‘downwards and inwards’, i.e towards the base of the ovary (ovule revolute; apotropous). The taxonomic/phylogenetic significance of the distinction was recognised in the Engler and Prantl classification, where it was emphasized as the major difference between the important orders Geraniales and Sapindales, together involving some 50 families. For the present purpose, the available data seem applicable only to pendulous and ascending ovules, and then only in the context of axile placentation, as expressed by the character states defined above. Where not stated explicitly in published family descriptions, the condition has been tentatively deduced by combining compiled (sparse) information on ovule and raphe orientation. However, the principle seems independent of whether ovules ascend or descend, and ought sometimes also to be applicable where the placentation is apical, basal or parietal, provided there are more than two ovules on the placenta. It is difficult or impossible to glean much reliable data on this interesting aspect from existing taxonomic descriptions, and there is evidently a fine opportunity for making original observations.
‘Raphe’: of (more or less) anatropous ovules (q.v.), being a cord or ridge of fibrovascular tissue connecting the base of the nucellus with the placenta which morphologically represents the adherent funicle. It is ‘ventral’ if located on the side of the ovule against the axis, ‘dorsal’ if away from it, or ‘lateral’ if somewhere intermediate.
‘Orthotropous’: (ovule) straight, with the micropyle at one end and the basal funicular attachment at the other. Embryo straight.
‘Loment’: a fruit derived from a single carpel, which at maturity breaks transversely into (usually one-seeded) segments.
‘Follicle’: a fruit derived from a single carpel, which dehisces only along the ventral suture.
‘Achene’: a fruit derived from a single carpel which is small, hard, dry, one-seeded, and with a tight, thin pericarp.
‘Samaroid’: a winged fruit derived from a single carpel.
‘Nucular’: a fruit which is nutlike, but derived from a single carpel.
‘Drupaceous’: a fruit which is drupelike, but derived from a single carpel.
‘Baccate’: a fruit which is berrylike, but derived from a single carpel (a ‘berrylet’).
‘Aggregate fruit’: one representing aggregation (clustering or coherence) of the discrete units (carpels) from a single synstylous, semicarpous or apocarpous gynoecium (e.g. blackberry, buttercup). Not to be confused with ‘multiple fruits’ (q.v.) derived from more than one flower.
‘Indehiscent’: a fruit with no precise, anatomical mechanism for opening to release the seeds (rotting, irregularly rupturing, ruptured by seedling germination, opened by external agencies, etc.).
‘Schizocarp’: a syncarpous fruit which splits longitudinally into non- or tardily dehiscent, fruitlike parts (mericarps, these generally corresponding with locules or locelli). Useage restricting the term to dry, bipartite fruits (Umbelliferae, Aceraceae, e.g. Lawrence 1951) is idiosyncratic and inconvenient.
‘Lomentaceous’: a syncarpous fruit which breaks transversely into segments, resembling a loment (q.v.).
‘Berrylet’: a berrylike mericarp.
‘Follicle’: a fruit derived from a single carpel, which dehisces only along the ventral suture.
‘Nutlet’: a nutlike mericarp.
‘Samaroid’: winged.
‘Legume’: a fruit derived from a single carpel, which dehisces both dorsally (along the placenta) and ventrally: the commonest type in Leguminosae.
‘Drupelet’: a drupelike mericarp.
‘Capsular-indehiscent’: cf. ‘capsule’ — relatively thin walled and containing free seeds, but indehiscent.
‘Achene-like’: small, hard, dry, one-seeded, the pericarp tight and thin — cf. an achene (q.v.), but from a syncarpous gynoecium.
‘Silicula’: dry, bilocular, of two carpels, longitudinally two-valved (q.v. ‘valved’), length less than three times breadth.
‘Siliqua’: dry, bilocular, of two carpels, longitudinally two-valved (q.v. ‘valved’), length at least three times breadth.
‘Berry’: a fleshy syncarp, without a stony layer, usually several to many seeded.
‘Drupe’: a fleshy syncarp, with the one or more seeds surrounded by a stony layer.
‘Nut’: an indehiscent, one-seeded syncarp, with a hard, dry, woody pericarp from which the seed is free.
‘Cypsella’: an ‘achene’ from two carpels, invested by the adnate calyx.
‘Samara’: an indehiscent syncarp, winged by extension of the fruit wall.
‘Caryopsis’: syncarpous but one celled, one seeded, superior, and with the thin pericarp united to the seed (the ‘grain’ typical of grasses.
‘Syncarp’: a fruit representing two or more fused carpels.
‘Valved’: opening by a flap (as opposed to a slit).
This character is widely inapplicable to Monocots, where the single cotyledon is commonly partly below ground and partly raised above it, and where structures of obscure homologies may be involved (e.g. a coleoptile, q.v.).
Data from Tillich (1995).
Data for Monocots only, from Tillich (1995).
Unfortunately, ‘circular in t.s.’ and ‘dorsiventrally flattened’ are not reliably indicative of anatomically unifacial versus bifacial.
Data from Tillich (1995).
Some published compilations and taxonomists’ generalizations (e.g. Cronquist 1981) are probably bedevilled by spurious positives.
Encoding has been organized here on the assumption that the most generally useful expression for taxonomic purposes will be ‘iridoids sought and found in at least one representative of the family’, contrasted with ‘iridoids sought in the family, but not found’.
Though of much taxonomic interest, as with most data on ‘esoteric’ features, these require careful interpretation for use in taxonomic analyses. There is often variation re presence and constitution of iridoids within families, but for most relatively few representatives have been screened. Most of the information in the source references seems to represent analyses of leaf material, but a positive record for Menyanthes (used in published cladistic studies) represents loganin reported for the rhizome, the leaves having been found Ehrlich-negative.
Explicit information on ‘absence’ is scarce (in the present data, much of it derives from the negative Ehrlich tests recorded by Gibbs). In employing the present compilation, therefore, ‘iridoids absent’ cannot be routinely regarded as implicit.
For sources of data, see references tagged PP in the References. Re problems in recording CAM/C3, see Martin et al. 1982/
The original aims in providing the alternative classificatory assessments for Dicotyledons of Dahlgren and Cronquist were as follows:
(a), to permit direct comparisons, using INTKEY, of the rival family assignments from Order to Superorder and Subclass.
(b), to assist users of taxonomic schemes desirous of selecting parsimonious but taxonomically balanced samples for experimental work
(c), to encourage people interested in classification and phylogenetic hypotheses to compare the rival schemes directly, both with one another and with the descriptive data they purport to reflect. In fact, it has long been apparent (cf. Young and Watson 1970) that Cronquist’s largest Subclasses of the Dicotyledons, Rosidae and Dilleniidae, have no taxonomic merit. Dahlgren’s scheme (viewed in conjunction with his diagrammatic representation) is far superior, but his classification could be much improved, especially in connection with experimentalists’ requirements, by superimposing the Young and Watson ‘Crassinucelli’/‘Tenuinucelli’ subdivision on his 24 Superorders. For the present purpose, ‘Crassinucelli’/‘Tenuinucelli’ status has been assigned on correlated attributes, the nucellus being the best predictor (though not absolutely reliable) when data are available.
Classification of Dicots into meaningful Orders is easier, and the Dahlgren and Cronquist schemes extensively coincide. Comparisons between the contents of their orders, and assessments of the character state distributions they supposedly reflect, are easily conducted by applying INTKEY (see below).
Various details of the (preferred) Dahlgren scheme for Dicots have been adjusted here, mainly to account for new information (e.g. families recently described, referal of glucosinolate families to Capparales, and re-assignments in relation to the Araliiflorae/Corniflorae conundrum). For Monocots, the Dahlgren et al (1985) classification alone was incorporated, although it is evidently far from the last word. Earlier schemes (including Cronquist’s) are rendered extensively useless in the modern context by gross sensu lato treatment of the family Liliaceae.
The exciting classificatory ideas (exemplified in Chase et al 1993 and summarised in the APG classification) now emerging from comparative nucleic acid studies will certainly inspire a completely revised system within the next few years; but a thoroughly convincing, complete and formalised one will depend upon achieving congruent results from at least two genes (nuclear, as well as chloroplast), and probably more. A commonsense approach to assessing the phylogenetic credentials of this and any other taxonomic classification will require properly organised scrutiny of conventional character state distributions at all levels, as will preparation of comparative group descriptions: operations which are rendered relatively easy by the present package, and which were specifically evisaged in its design (Watson and Dallwitz, 1992).
It has become fashionable in the nineteen nineties to propose large scale re-circumscriptions of families, based on cladistic morphological studies using small sets of descriptive data, ‘sanitized’ to exclude such real life inconveniences as intra-taxon variation. Such productions are not only unconvincing from the standpoint of taxonomic first principles, but are commonly incomplete in being unaccompanied by the revised family descriptions needed for practical implementation in floras and incorporation in syntheses such as the present one. Again, we point out that our freely available package is appropriate for application in such operations.
The present Intkey package permits most of the commonly encountered Angiosperm generic names to be referred to a family. For easy assignment of names which cannot be located here to Cronquist’s often broadly circumscribed families, we recommend the GRIN database of plant names (Wiersema 1997, accessible at http://www.ars-grin.gov/npgs/tax/taxfam.html). Sensu stricto family assignments of Dicot genera corresponding with ours can mostly be obtained from Airy Shaw (1973), who also provides near-comprehensive cross referencing of synonyms.
Tropical and southern hemisphere families are poorly represented — contributions for these are especially welcome!
Cite this publication as: ‘L. Watson and M. J. Dallwitz (1992 onwards). The Families of Flowering Plants: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 27th September 2000. http://biodiversity.uno.edu/delta/’. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993, 1995, 2000), and Watson and Dallwitz (1991) should also be cited (see References).