Most species of Asparagales areherbaceousperennials, although some areclimbers and some are trees or shrubs. The order also contains manygeophytes (bulbs, corms, and various kinds of tuber). Theleaves of almost all species form a tightrosette, either at the base of the plant or at the end of thestem, but occasionally along the stem. Theflowers are not particularly distinctive, being 'lily type', with sixtepals and up to sixstamens. One of the defining characteristics (synapomorphies) of the order is the presence ofphytomelanin, a black pigment present in the seed coat, creating a dark crust. Phytomelanin is found in most families of the Asparagales (although not inOrchidaceae, thought to be the sister-group of the rest of the order).
The order Asparagales takes its name from thetype familyAsparagaceae and has only recently been recognized in classification systems. The order is clearly circumscribed on the basis ofmolecular phylogenetics, but it is difficult to definemorphologically since its members are structurally diverse. The order was first put forward byHuber in 1977 and later taken up in theDahlgren system of 1985 and then theAngiosperm Phylogeny Group systems. Before this, many of its families were assigned to the old orderLiliales, which was redistributed over three orders,Liliales, Asparagales, andDioscoreales, based on molecular phylogenetics. The boundaries of the Asparagales and of its families have undergone a series of changes in recent years; future research may lead to further changes and ultimately greater stability.
The order is thought to have firstdiverged from other related monocots some 120–130 million years ago (early in theCretaceous period), although given the difficulty in classifying the families involved, estimates are likely to be uncertain.
Although most species in the order areherbaceous, some no more than 15 cm high, there are a number ofclimbers (e.g., some species ofAsparagus), as well as several genera formingtrees (e.g.Agave,Cordyline,Yucca,Dracaena,Aloidendron), which can exceed 10 m in height.Succulent genera occur in several families (e.g.Aloe).
Almost all species have a tight cluster ofleaves (arosette), either at the base of the plant or at the end of a more-or-less woodystem as withYucca. In some cases, the leaves are produced along the stem. Theflowers are in the main not particularly distinctive, being of a general 'lily type', with sixtepals, either free or fused from the base and up to sixstamina. They are frequently clustered at the end of the plant stem.
The Asparagales are generally distinguished from theLiliales by the lack of markings on the tepals, the presence ofseptal nectaries in theovaries, rather than the bases of the tepals or stamen filaments, and the presence ofsecondary growth. They are generallygeophytes, but with linear leaves, and a lack of finereticular venation.
Theseeds characteristically have the external epidermis either obliterated (in most species bearing fleshy fruit), or if present, have a layer of black carbonaceousphytomelanin in species with dry fruits (nuts). The inner part of the seed coat is generally collapsed, in contrast to Liliales whose seeds have a well developed outer epidermis, lack phytomelanin, and usually display a cellular inner layer.
The orders which have been separated from the old Liliales are difficult to characterize. No single morphological character appears to be diagnostic of the order Asparagales.
The flowers of Asparagales are of a general type among thelilioid monocots. Compared to Liliales, they usually have plaintepals without markings in the form of dots. Ifnectaries are present, they are in thesepta of theovaries rather than at the base of the tepals orstamens.
Those species which have relatively large dry seeds have a dark, crust-like (crustose) outer layer containing the pigment phytomelan. However, some species with hairy seeds (e.g.Eriospermum, family Asparagaceaes.l.), berries (e.g.Maianthemum, family Asparagaceaes.l.), or highly reduced seeds (e.g. orchids) lack this dark pigment in their seed coats. Phytomelan is not unique to Asparagales (i.e. it is not asynapomorphy) but it is common within the order and rare outside it.[6] The inner portion of the seed coat is usually completely collapsed. In contrast, the morphologically similar seeds of Liliales have no phytomelan, and usually retain a cellular structure in the inner portion of the seed coat.[7]
Most monocots are unable to thicken their stems once they have formed, since they lack the cylindricalmeristem present in other angiosperm groups. Asparagales have a method of secondary thickening which is otherwise only found inDioscorea (in the monocot order Disoscoreales). In a process called 'anomalous secondary growth', they are able to create new vascular bundles around which thickening growth occurs.[8]Agave,Yucca,Aloidendron,Dracaena,Nolina andCordyline can become massive trees, albeit not of the height of the tallest dicots, and with less branching.[6] Other genera in the order, such asLomandra andAphyllanthes, have the same type of secondary growth but confined to their underground stems.
Microsporogenesis (part ofpollen formation) distinguishes some members of Asparagales from Liliales. Microsporogenesis involves a cell dividing twice (meiotically) to form four daughter cells. There are two kinds of microsporogenesis: successive and simultaneous (although intermediates exist). In successive microsporogenesis, walls are laid down separating the daughter cells after each division. In simultaneous microsporogenesis, there is no wall formation until all four cellnuclei are present. Liliales all have successive microsporogenesis, which is thought to be the primitive condition in monocots. It seems that when the Asparagales first diverged they developed simultaneous microsporogenesis, which the 'lower' Asparagales families retain. However, the 'core' Asparagales (seePhylogenetics) have reverted to successive microsporogenesis.[9]
The Asparagales appear to be unified by a mutation affecting theirtelomeres (a region of repetitiveDNA at the end of achromosome). The typical 'Arabidopsis-type' sequence of bases has been fully or partially replaced by other sequences, with the 'human-type' predominating.[10]
Other apomorphic characters of the order according to Stevens are: the presence of chelidonic acid, anthers longer than wide, tapetal cells bi- to tetra-nuclear, tegmen not persistent, endosperm helobial, and loss of mitochondrial genesdh3.[1]
According totelomere sequence, at least two evolutionary switch-points happened within the order. The basal sequence is formed by TTTAGGG like in the majority of higher plants. Basal motif was changed to vertebrate-like TTAGGG and finally, the most divergent motif CTCGGTTATGGG appears inAllium.
Ascircumscribed within theAngiosperm Phylogeny Group system Asparagales is the largestorder within themonocotyledons, with 14 families, 1,122genera and about 25,000–42,000species, thus accounting for about 50% of all monocots and 10–15% of theflowering plants (angiosperms).[11][12] The attribution of botanical authority for the name Asparagales belongs toJohann Heinrich Friedrich Link (1767–1851) who coined the word 'Asparaginae' in 1829 for a higher order taxon that includedAsparagus[13] although Adanson and Jussieau had also done so earlier (see History). Earlier circumscriptions of Asparagales attributed the name toBromhead (1838), who had been the first to use the term 'Asparagales'.[4]
Thetype genus,Asparagus, from which the name of the order is derived, was described byCarl Linnaeus in 1753, with ten species.[14] He placedAsparagus within theHexandria Monogynia (sixstamens, onecarpel) in hissexual classification in theSpecies Plantarum.[15] The majority oftaxa now considered to constitute Asparagales have historically been placed within the very large and diverse family,Liliaceae. The family Liliaceae was first described byMichel Adanson in 1763,[16] and inhis taxonomic scheme he created eight sections within it, including the Asparagi withAsparagus and three other genera.[17] The system of organising genera into families is generally credited toAntoine Laurent de Jussieu who formally described both the Liliaceae and the type family of Asparagales, theAsparagaceae, as Lilia and Asparagi, respectively, in 1789.[18] Jussieu established thehierarchical system oftaxonomy (phylogeny), placingAsparagus and related genera within adivision ofMonocotyledons, aclass (III) ofStamina Perigynia[19] and 'order' Asparagi, divided into three subfamilies.[20] The use of the termOrdo (order) at that time was closer to what we now understand as Family, rather than Order.[21][22] In creatinghis scheme he used a modified form of Linnaeus' sexual classification but using the respective topography of stamens to carpels rather than just their numbers. While De Jussieu'sStamina Perigynia also included a number of 'orders' that would eventually form families within the Asparagales such as the Asphodeli (Asphodelaceae), Narcissi (Amaryllidaceae) and Irides (Iridaceae), the remainder are now allocated to other orders. Jussieu's Asparagi soon came to be referred to asAsparagacées in the French literature (Latin: Asparagaceae).[23] Meanwhile, the 'Narcissi' had been renamed as the 'Amaryllidées' (Amaryllideae) in 1805, byJean Henri Jaume Saint-Hilaire, usingAmaryllis as the type species rather thanNarcissus, and thus has the authority attribution forAmaryllidaceae.[24] In 1810,Brown proposed that a subgroup of Liliaceae be distinguished on the basis of the position of theovaries and be referred to as Amaryllideae[25] and in 1813de Candolle described Liliacées Juss. and Amaryllidées Brown as two quite separate families.[26]
The literature on the organisation of genera into families and higher ranks became available in the English language withSamuel Frederick Gray'sA natural arrangement of British plants (1821).[27] Gray used a combination of Linnaeus' sexual classification and Jussieu's natural classification to group together a number of families having in common six equal stamens, a single style and a perianth that was simple and petaloid, but did not use formal names for these higher ranks. Within the grouping he separated families by the characteristics of their fruit and seed. He treated groups of genera with these characteristics as separate families, such as Amaryllideae, Liliaceae, Asphodeleae and Asparageae.[28]
Thecircumscription of Asparagales has been a source of difficulty for many botanists from the time ofJohn Lindley (1846), the other important British taxonomist of the early nineteenth century. In hisfirst taxonomic work,An Introduction to the Natural System of Botany (1830)[29] he partly followed Jussieu by describing a subclass he called Endogenae, or Monocotyledonous Plants (preserving de Candolle'sEndogenæ phanerogamæ)[30] divided into two tribes, thePetaloidea andGlumaceae. He divided the former, often referred to as petaloid monocots, into 32 orders, including the Liliaceae (defined narrowly), but also most of the families considered to make up the Asparagales today, including theAmaryllideae.
By 1846, in his final scheme[31] Lindley had greatly expanded and refined the treatment of the monocots, introducing both an intermediate ranking (Alliances) and tribes within orders (i.e. families). Lindley placed the Liliaceae within theLiliales, but saw it as aparaphyletic ("catch-all") family, being all Liliales not included in the other orders, but hoped that the future would reveal some characteristic that would group them better. The order Liliales was very large and included almost all monocotyledons with colourful tepals and without starch in their endosperm (thelilioid monocots). The Liliales was difficult to divide into families because morphological characters were not present in patterns that clearly demarcated groups. This kept the Liliaceae separate from the Amaryllidaceae (Narcissales). Of these, Liliaceae[32] was divided into eleven tribes (with 133 genera) and Amaryllidaceae[33] into four tribes (with 68 genera), yet both contained many genera that would eventually segregate to each other's contemporary orders (Liliales and Asparagales respectively). The Liliaceae would be reduced to a small 'core' represented by the tribe Tulipae, while large groups suchScilleae andAsparagae would become part of Asparagales either as part of the Amaryllidaceae or as separate families. While of the Amaryllidaceae, theAgaveae would be part of Asparagaceae but theAlstroemeriae would become a family within theLiliales.
The number of known genera (and species) continued to grow and by the time of the next major British classification, that of theBentham & Hooker system in 1883 (published in Latin) several of Lindley's other families had been absorbed into the Liliaceae.[34] They used the term 'series' to indicate suprafamilial rank, with seven series of monocotyledons (including Glumaceae), but did not use Lindley's terms for these. However, they did place the Liliaceous and Amaryllidaceous genera into separate series. The Liliaceae[35] were placed in series Coronariae, while the Amaryllideae[36] were placed in series Epigynae. The Liliaceae now consisted of twenty tribes (including Tulipeae, Scilleae and Asparageae), and the Amaryllideae of five (including Agaveae and Alstroemerieae). An important addition to the treatment of the Liliaceae was the recognition of theAllieae[37] as a distinct tribe that would eventually find its way to the Asparagales as the subfamilyAllioideae of the Amaryllidaceae.
The appearance ofCharles Darwin'sOrigin of Species in 1859 changed the way that taxonomists considered plant classification, incorporating evolutionary information into their schemata. TheDarwinian approach led to the concept ofphylogeny (tree-like structure) in assembling classification systems, starting withEichler.[38]Eichler, having established ahierarchical system in which the flowering plants (angiosperms) were divided intomonocotyledons anddicotyledons, further divided into former into seven orders. Within theLiliiflorae were seven families, including Liliaceae and Amaryllidaceae. Liliaceae includedAllium andOrnithogalum (modernAllioideae) andAsparagus.[39]
Engler, in hissystem developed Eichler's ideas into a much more elaborate scheme which he treated in a number of works includingDie Natürlichen Pflanzenfamilien (Engler andPrantl 1888)[40] andSyllabus der Pflanzenfamilien (1892–1924).[41] In his treatment of Liliiflorae the Liliineae were a suborder which included both families Liliaceae and Amaryllidaceae. The Liliaceae[42] had eight subfamilies and the Amaryllidaceae[43] four. In this rearrangement of Liliaceae, with fewer subdivisions, the core Liliales were represented as subfamilyLilioideae (with Tulipae and Scilleae as tribes), the Asparagae were represented as Asparagoideae and theAllioideae was preserved, representing the alliaceous genera.Allieae,Agapantheae andGilliesieae were the three tribes within this subfamily.[44] In the Amaryllidaceae, there was little change from the Bentham & Hooker. A similar approach was adopted byWettstein.[45]
In the twentieth century theWettstein system (1901–1935) placed many of the taxa in an order called 'Liliiflorae'.[46] NextJohannes Paulus Lotsy (1911) proposed dividing theLiliiflorae into a number of smaller families includingAsparagaceae.[47] ThenHerbert Huber (1969, 1977), following Lotsy's example, proposed that the Liliiflorae be split into four groups including the 'Asparagoid'Liliiflorae.[48][49]
These various proposals to separate small groups of genera into more homogeneous families made little impact till that ofDahlgren (1985) incorporating new information includingsynapomorphy. Dahlgren developed Huber's ideas further and popularised them, with a major deconstruction of existing families into smaller units. They created a neworder, calling it Asparagales. This was one of five orders within the superorder Liliiflorae.[53] Where Cronquist saw one family, Dahlgren saw forty distributed over three orders (predominantlyLiliales and Asparagales).[54][55] Over the 1980s, in the context of a more general review of the classification ofangiosperms, the Liliaceae were subjected to more intense scrutiny. By the end of that decade, theRoyal Botanic Gardens at Kew, theBritish Museum of Natural History and theEdinburgh Botanical Gardens formed a committee to examine the possibility of separating the family at least for the organization of theirherbaria. That committee finally recommended that 24 new families be created in the place of the original broad Liliaceae, largely by elevating subfamilies to the rank of separate families.[56]
The order Asparagales as currentlycircumscribed has only recently been recognized in classification systems, through the advent ofphylogenetics. The 1990s saw considerable progress in plant phylogeny and phylogenetic theory, enabling a phylogenetic tree to be constructed for all of the flowering plants. The establishment of major new clades necessitated a departure from the older but widely used classifications such as Cronquist and Thorne based largely on morphology rather than genetic data. This complicated the discussion about plant evolution and necessitated a major restructuring.[57]rbcL gene sequencing and cladistic analysis of monocots had redefined theLiliales in 1995.[58][59] from four morphological orderssensuDahlgren. The largest clade representing the Liliaceae, all previously included in Liliales, but including both the Calochortaceae and Liliaceaesensu Tamura. This redefined family, that became referred to as core Liliales, but corresponded to the emerging circumscription of theAngiosperm Phylogeny Group (1998).[60]
From theDahlgren system of 1985 onwards, studies based mainly on morphology had identified the Asparagales as a distinct group, but had also included groups now located in Liliales, Pandanales and Zingiberales.[62] Research in the 21st century has supported themonophyly of Asparagales, based on morphology, 18S rDNA, and other DNA sequences,[63][64][65][66][67] although some phylogenetic reconstructions based on molecular data have suggested that Asparagales may be paraphyletic, with Orchidaceae separated from the rest.[68] Within the monocots, Asparagales is thesister group of thecommelinid clade.[57]
Thiscladogram shows the placement of Asparagales within the orders ofLilianaesensu Chase & Reveal (monocots) based on molecular phylogenetic evidence.[69][61][70][71] Thelilioid monocot orders are bracketed, namelyPetrosaviales,Dioscoreales,Pandanales,Liliales and Asparagales.[72] These constitute aparaphyletic assemblage, that is groups with a common ancestor that do not include all direct descendants (in this case commelinids as the sister group to Asparagales); to form a clade, all the groups joined by thick lines would need to be included. While Acorales and Alismatales have been collectively referred to as "alismatid monocots" (basal or early branching monocots), the remaining clades (lilioid andcommelinid monocots) have been referred to as the "core monocots".[73] The relationship between the orders (with the exception of the two sister orders) ispectinate, that is diverging in succession from the line that leads to the commelinids.[70] Numbers indicatecrown group (most recent common ancestor of the sampled species of the clade of interest) divergence times inmya (million years ago).[71]
Aphylogenetic tree for the Asparagales, generally to family level, but including groups which were recently and widely treated as families but which are now reduced to subfamily rank, is shown below.[11][1]
The tree shown above can be divided into a basal paraphyletic group, the 'lower Asparagales (asparagoids)', from Orchidaceae to Asphodelaceae,[74] and a well-supported monophyletic group of 'core Asparagales' (higher asparagoids), comprising the two largest families, Amaryllidaceaesensu lato and Asparagaceaesensu lato.[1]
Two differences between these two groups (although with exceptions) are: the mode ofmicrosporogenesis and the position of the ovary. The 'lower Asparagales' typically have simultaneous microsporogenesis (i.e. cell walls develop only after bothmeiotic divisions), which appears to be anapomorphy within the monocots, whereas the 'core Asparagales' have reverted to successive microsporogenesis (i.e. cell walls develop after each division).[63] The 'lower Asparagales' typically have aninferior ovary, whereas the 'core Asparagales' have reverted to asuperior ovary. A 2002 morphological study by Rudall treated possessing an inferior ovary as asynapomorphy of the Asparagales, stating that reversions to a superior ovary in the 'core Asparagales' could be associated with the presence of nectaries below the ovaries.[75] However, Stevens notes that superior ovaries are distributed among the 'lower Asparagales' in such a way that it is not clear where to place the evolution of different ovary morphologies. The position of the ovary seems a much more flexible character (here and in otherangiosperms) than previously thought.[1]
TheAPG III system when it was published in 2009, greatly expanded the familiesXanthorrhoeaceae,Amaryllidaceae, andAsparagaceae.[11] Thirteen of the families of the earlierAPG II system were thereby reduced to subfamilies within these three families. The expanded Xanthorrhoeaceae is now called "Asphodelaceae".[76] The APG II families (left) and their equivalent APG III subfamilies (right) are as follows:
Orchidaceae is possibly the largest family of allangiosperms (onlyAsteraceae might – or might not – be more speciose) and hence by far the largest in the order. TheDahlgren system recognized three families of orchids, but DNA sequence analysis later showed that these families arepolyphyletic and so should be combined. Several studies suggest (with high bootstrap support) that Orchidaceae is the sister of the rest of the Asparagales.[65][66][67][77] Other studies have placed the orchids differently in the phylogenetic tree, generally among theBoryaceae-Hypoxidaceae clade.[78][63][58][79][80] The position of Orchidaceae shown above seems the best current hypothesis,[1] but cannot be taken as confirmed.
Orchids have simultaneous microsporogenesis and inferior ovaries, two characters that are typical of the 'lower Asparagales'. However, their nectaries are rarely in the septa of the ovaries, and most orchids have dust-like seeds, atypical of the rest of the order. (Some members ofVanilloideae andCypripedioideae have crustose seeds, probably associated with dispersal by birds and mammals that are attracted by fermenting fleshy fruit releasing fragrant compounds, e.g.vanilla.)
In terms of the number of species, Orchidaceae diversification is remarkable, with recent estimations suggesting that despite the old origin of the family dating back to the late cretaceous,[81][82] modern orchid diversity originated mostly during the last 5 million years.[83] However, although the other Asparagales may be less rich in species, they are more variable morphologically, including tree-like forms.
The four families excludingBoryaceae form a well-supported clade in studies based on DNA sequence analysis. All four contain relatively few species, and it has been suggested that they be combined into one family under the name Hypoxidaceaesensu lato.[84] The relationship between Boryaceae (which includes only two genera,Borya andAlania), and other Asparagales has remained unclear for a long time. The Boryaceae aremycorrhizal, but not in the same way as orchids. Morphological studies have suggested a close relationship between Boryaceae and Blandfordiaceae.[63] There is relatively low support for the position of Boryaceae in the tree shown above.[65]
The relationship shown betweenIxioliriaceae andTecophilaeaceae is still unclear. Some studies have supported a clade of these two families,[65] others have not.[78] The position ofDoryanthaceae has also varied, with support for the position shown above,[66] but also support for other positions.[65]
The clade fromIridaceae upwards appears to have stronger support. All have some genetic characteristics in common, having lost Arabidopsis-typetelomeres.[85] Iridaceae is distinctive among the Asparagales in the unique structure of theinflorescence (a rhipidium), the combination of an inferior ovary and three stamens, and the common occurrence of unifacial leaves whereas bifacial leaves are the norm in other Asparagales.
Members of the clade fromIridaceae upwards have infra-locular septal nectaries, which Rudall interpreted as a driver towards secondarily superior ovaries.[75]
The next node in the tree (Xanthorrhoeaceaesensu lato + the 'core Asparagales') has strong support.[86] 'Anomalous' secondary thickening occurs among this clade, e.g. inXanthorrhoea (family Asphodelaceae) andDracaena (family Asparagaceaesensu lato), with species reaching tree-like proportions.
The 'core Asparagales', comprising Amaryllidaceaesensu lato and Asparagaceaesensu lato, are a strongly supported clade,[66] as are clades for each of the families. Relationships within these broadly defined families appear less clear, particularly within the Asparagaceaesensu lato. Stevens notes that most of its subfamilies are difficult to recognize, and that significantly different divisions have been used in the past, so that the use of a broadly defined family to refer to the entire clade is justified.[1] Thus the relationships among subfamilies shown above, based onAPWeb as of December 2010[update], is somewhat uncertain.
Several studies have attempted to date the evolution of the Asparagales, based on phylogenetic evidence. Earlier studies[87][88] generally give younger dates than more recent studies,[78][89] which have been preferred in the table below.
Approx. date in Millions of Years Ago
Event
133-120
Origin of Asparagales, i.e. first divergence from other monocots[78][89]
93
Split between Asphodelaceae and the 'core group' Asparagales[78]
A 2009 study suggests that the Asparagales have the highest diversification rate in the monocots, about the same as the orderPoales, although in both orders the rate is little over half that of theeudicot orderLamiales, the clade with the highest rate.[89]
The taxonomic diversity of the monocotyledons is described in detail by Kubitzki.[90][91] Up-to-date information on the Asparagales can be found on theAngiosperm Phylogeny Website.[1]
The APG III system's family circumscriptions are being used as the basis of the Kew-hostedWorld Checklist of Selected Plant Families.[92] With this circumscription, the order consists of 14 families (Dahlgren had 31)[53] with approximately 1120 genera and 26000 species.[1]
The earlier 2003 version,APG II, allowed 'bracketed' families, i.e. families which could either be segregated from more comprehensive families or could be included in them. These are the families given under "including" in the list above. APG III does not allow bracketed families, requiring the use of the more comprehensive family; otherwise the circumscription of the Asparagales is unchanged. A separate paper accompanying the publication of the 2009 APG III system provided subfamilies to accommodate the families which were discontinued.[93] The first APG system of1998 contained some extra families, included in square brackets in the list above.
Two older systems which use the order Asparagales are theDahlgren system[62] and theKubitzki system.[90] The families included in the circumscriptions of the order in these two systems are shown in the first and second columns of the table below. The equivalent family in the modern APG III system (see below) is shown in the third column. Note that although these systems may use the same name for a family, the genera which it includes may be different, so the equivalence between systems is only approximate in some cases.
Families included in Asparagales in three systems which use this order
Dahlgren system
Kubitzki system
APG III system
–
Agapanthaceae
Amaryllidaceae: Agapanthoideae
Agavaceae
Asparagaceae: Agavoideae
Alliaceae
Amaryllidaceae: Allioideae
Amaryllidaceae
Amaryllidaceae: Amaryllidoideae
–
Anemarrhenaceae
Asparagaceae: Agavoideae
Anthericaceae
Asparagaceae: Agavoideae
Aphyllanthaceae
Asparagaceae: Aphyllanthoideae
Asparagaceae
Asparagaceae: Asparagoideae
Asphodelaceae
Asphodelaceae: Asphodeloideae
Asteliaceae
Asteliaceae
–
Behniaceae
Asparagaceae: Agavoideae
Blandfordiaceae
Blandfordiaceae
–
Boryaceae
Boryaceae
Calectasiaceae
—
Not in Asparagales (family Dasypogonaceae, unplaced as to order, clade commelinids)
Convallariaceae
Asparagaceae: Convallarioideae
Cyanastraceae
–
Tecophilaeaceae
Dasypogonaceae
–
Not in Asparagales (family Dasypogonaceae, unplaced as to order, clade commelinids)
Doryanthaceae
Doryanthaceae
Dracaenaceae
Asparagaceae: Convallarioideae
Eriospermaceae
Asparagaceae: Convallarioideae
Hemerocallidaceae
Asphodelaceae: Hemerocallidoideae
Herreriaceae
Asparagaceae: Agavoideae
Hostaceae
Asparagaceae: Agavoideae
Hyacinthaceae
Asparagaceae: Scilloideae
Hypoxidaceae
Hypoxidaceae
–
Iridaceae
Iridaceae
Ixioliriaceae
Ixioliriaceae
–
Johnsoniaceae
Asphodelaceae: Hemerocallidoideae
Lanariaceae
Lanariaceae
Luzuriagaceae
–
Not in Asparagales (family Alstroemeriaceae, order Liliales)
–
Lomandraceae
Asparagaceae: Lomandroideae
Nolinaceae
Asparagaceae: Convallarioideae
–
Orchidaceae
Orchidaceae
Philesiaceae
–
Not in Asparagales (family Philesiaceae, order Liliales)
^The name 'Alliaceae' has also been used for the expanded family comprising the Alliaceaesensu stricto, Amaryllidaceae and Agapanthaceae (e.g. in theAPG II system). 'Amaryllidaceae' is used as aconserved name inAPG III.
Dimitri, M., ed. (1987),Enciclopedia Argentina de Agricultura y Jardinería, Tomo I. Descripción de plantas cultivadas, Buenos Aires: ACME S.A.C.I. *Hedges, S. Blair; Kumar, Sudhir, eds. (2009),The timetree of life, Oxford: Oxford University Press,ISBN978-0-19-156015-6
Kubitzki, K., ed. (1998),The Families and Genera of Vascular Plants, Vol. III, Monocotyledons: Lilianae (except Orchidaceae), Berlin: Springer-Verlag,ISBN978-3-540-64060-8
Kubitzki, K., ed. (2006),The Families and Genera of Vascular Plants, Vol. IV, Monocotyledons: Alismatanae and Commelinanae (except Gramineae), Berlin: Springer-Verlag,ISBN978-3-540-64061-5
Simpson, Michael G. (2005), "Asparagales",Plant Systematics, Elsevier Inc., pp. 163–165,ISBN978-0-12-644460-5
Davis, Jerrold I.; Mcneal, Joel R.; Barrett, Craig F.;Chase, Mark W.; Cohen, James I.; Duvall, Melvin R.; Givnish, Thomas J.; Graham, Sean W.; Petersen, Gitte; Pires, J. Chris; Seberg, Ole; Stevenson, Dennis W.; Leebens-Mack, Jim (2013), "Contrasting patterns of support among plastid genes and genomes for major clades of the monocotyledons",Early Events in Monocot Evolution:315–349,doi:10.1017/CBO9781139002950.015,ISBN978-1-139-00295-0,{{citation}}: CS1 maint: work parameter with ISBN (link) inWilkin & Mayo (2013)
Nadot, S.; Penet, L.; Dreyer, L. D.; Forchioni, A.; Ressayre, A. (2006),Aperture pattern and microsporogenesis in Asparagales., pp. 197–203, inColumbus et al. (2006)
Seberg, Ole (2007), "Xanthorrhoeaceae", in Heywood, Vernon H.; Brummitt, Richard K.; Seberg, Ole & Culham, Alastair (eds.),Flowering Plant Families of the World, Ontario, Canada: Firefly Books, pp. 406–407
Soltis, D.E.; Soltis, P.F.; Endress, P.K. & Chase, M.W. (2005), "Asparagales",Phylogeny and evolution of angiosperms, Sunderland, MA: Sinauer Associates, pp. 104–109
Adams, S. P.; Hartman, T. P. V.; Lim, K. Y.; Chase, M. W.; Bennett, M. D.; Leitch, I. J.; Leitch, A. R. (7 August 2001), "Loss and recovery of Arabidopsis-type telomere repeat sequences 5'-(TTTAGGG)n-3' in the evolution of a major radiation of flowering plants",Proceedings of the Royal Society B: Biological Sciences,268 (1476):1541–1546,doi:10.1098/rspb.2001.1726,PMC1088775,PMID11487399
Chase, M.W.; De Bruijn, A.; Cox, A.V.; Reeves, G.; Rudall, P.J.; Johnson, M.A.T.; Eguiarte, L.E. (2000), "Phylogenetics of Asphodelaceae (Asparagales): an analysis of plastidrbcL andtrnL-F DNA sequences",Annals of Botany,86 (5):935–951,Bibcode:2000AnBot..86..935C,doi:10.1006/anbo.2000.1262
Chase, M.W.; Reveal, J.L. & Fay, M.F. (2009), "A subfamilial classification for the expanded asparagalean families Amaryllidaceae, Asparagaceae and Xanthorrhoeaceae",Botanical Journal of the Linnean Society,161 (2):132–136,doi:10.1111/j.1095-8339.2009.00999.x
Davis, J.I.; Stevenson, D.W.; Petersen, G.; Seberg, O.; Campbell, L.M.; Freudenstein, J.V.; Goldman, D.H.; Hardy, C.R.; Michelangeli, F.A.; Simmons, M.P.; Specht, C.D.; Vergara-Silva, F.; Gandolfo, M. (2004), "A phylogeny of the monocots, as inferred fromrbcL andatpA sequence variation, and a comparison of methods for calculating jacknife and bootstrap values",Systematic Botany,29 (3):467–510,Bibcode:2004SysBo..29..467D,doi:10.1600/0363644041744365,S2CID13108898
Eguiarte, L.E. (1995), "Hutchinson (Agavales) vs. Huber y Dahlgren (Asparagales): análisis moleculares sobre la filogenia y evolucíón de la familia Agavaceaesensu Hutchinson dentro de las monocotiledóneas",Bull. Soc. Bot. México (in Spanish),56:45–56
Goldblatt, P. (2002), "Iridaceae", in Argus, George W. (ed.),Flora of North America north of Mexico, Vol. 26, New York: Oxford University Press, p. 348ff,ISBN978-0-19-515208-1
Huber, H. (1977), "The treatment of monocotyledons in an evolutionary system of classification", inKubitzki, Klaus (ed.),Flowering plants: Evolution and classification of higher categories. Symposium, Hamburg, September 8–12, 1976, Plant Systematics and Evolution, vol. Supplementum 1, Wien: Springer, pp. 285–298,doi:10.1007/978-3-7091-7076-2_18,ISBN978-3-211-81434-5
Li, X.-X. & Zhou, Z.-K. (2007), "The higher-level phylogeny of monocots based onmatK,rbcL and 18S rDNA sequences",Acta Phytotax. Sinica (in Chinese),45:113–133
Magallón, S. & Castillo, A. (2009), "Angiosperm diversification through time",American Journal of Botany,96 (1):349–365,doi:10.3732/ajb.0800060,PMID21628193
Mathew, Brian (1989), "Splitting the Liliaceae",The Plantsman,11 (2):89–105
McPherson, M.A. & Graham, S.W. (2001), "Inference of Asparagales phylogeny using a large chloroplast data set",Botany: 126
Patterson, T. B.; Givnish, T. J. (2002), "Phylogeny, concerted convergence, and phylogenetic niche conservatism in the core Liliales: insights fromrbcL andndhF sequence data",Evolution,56 (2):233–252,doi:10.1111/j.0014-3820.2002.tb01334.x,PMID11926492,S2CID39420833
Fajkus, P.; Peška, V.; Sitová, Z.; Fulnečková, J.; Dvořáčková, M.; Gogela, R.; Sýkorová, E.; Hapala, J. & Fajkus, J. (2016), "Allium telomeres unmasked: the unusual telomeric sequence (CTCGGTTATGGG)n is synthesized by telomerase.",The Plant Journal,85 (3):337–47,doi:10.1111/tpj.13115,PMID26716914
Rudall, P.; Furness, C.A.; Chase, M.W. & Fay, M.F. (1997), "Microsporogenesis and pollen sulcus type in Asparagales (Lilianae)",Can. J. Bot.,75 (3):408–430,Bibcode:1997CaJB...75..408R,doi:10.1139/b97-044
Sykorova, E.; Lim, K. Y.; Kunicka, Z.; Chase, M. W.; Bennett, M. D.; Fajkus, J.; Leitch, A. R. (22 September 2003), "Telomere variability in the monocotyledonous plant order Asparagales",Proceedings of the Royal Society B: Biological Sciences,270 (1527):1893–1904,doi:10.1098/rspb.2003.2446,PMC1691456,PMID14561302
Tapiero, Haim; Townsend, Danyelle M.; Tew, Kenneth D. (2004), "Alliaceae from organosulfur compounds in the prevention of human pathologies",Biomedicine & Pharmacotherapy,58 (3):183–193,doi:10.1016/j.biopha.2004.01.004,PMC6361170,PMID15164729
Lindley, John (1846),"Order LXII: Liliaceae – Lilyworts",The Vegetable Kingdom: or, The structure, classification, and uses of plants, illustrated upon the natural system, London: Bradbury, pp. 200–205, retrieved5 February 2014
Bentham, G.;Hooker, J.D. (1883),"Liliaceae",Genera plantarum ad exemplaria imprimis in herbariis kewensibus servata definita. Vol III Part II, vol. 3, London: L Reeve & Co., pp. 748–836, retrieved24 January 2014
