Editing Crocus (section)

== Taxonomy ==

=== History ===
{{
multiple image | header = | align = right | direction = | total_width= 400| float = 
| image1=BL Egerton 747 f. 24v.jpg|caption1=''Croci oriental''<br />[[Tractatus de Herbis]] ca.&nbsp;1300–1330|alt1=Illustration of crocus from illuminated manuscript dated between 1300 and 1330| width1={{#expr: (150 * 1900 /1425) round 0}}
| image2=Gercrocrop.jpg|caption2=Crocuses<br />[[John Gerard]] 1597|alt2=Illustration of crocus from John Gerard's Historie of Plants 1597]| width2={{#expr: (150 * 1900 /1425) round 0}}
| image3=Hortus Eystettensis, 1640 (BHL 45339 209) - Classis Aestiva 57.jpg|caption3=Crocuses<br />''[[Hortus Eystettensis]]'' 1613|alt3=Crocuses and other flowers from the Hortus Eystettensis of 1613| width3={{#expr: (150 * 1900 /1425) round 0}}
}}
The crocus was well known to the ancients,{{sfn|Caiola|Canini|2010}} being described at least as early as [[Theophrastus]] (c. 371{{snd}}c. 287 BC),{{efn|As a perfume (ἀρωμάτων) "καὶ πρὸς τούτοις τὸ κρόκινον· βέλτιστος δ’ ἐν Αἰγίνῃ καὶ Κιλικίᾳ (the saffron-perfume; the crocus which produces this is best in Aegina and Cilicia)". He also refers to the crocus as a spice (at 34), the word being interchangeable for either use{{sfn|Liddell|Scott|1996b}}}}{{sfn|Negbi|1989}} and was introduced into Britain by the Romans, where the saffron crocus was used as a [[dyestuff]]. It was reintroduced into Western Europe by the [[Crusaders]]. The crocus is mentioned in mediaeval and later [[herbals]], one of the earliest being the 14th century ''[[Tractatus de Herbis]].''{{sfn|BL|2022}}{{sfn|Pavord|2005|p=111}} [[William Turner (naturalist)|William Turner]] (1548) states that the crocus is referred to as saffron in English, implying that only ''C. sativus'' was known at that time.{{sfn|Turner|1548}} However, by 1597 [[John Gerard]] writes of "sundry sorts" and uses the term saffron and crocus as interchangeable. He included both spring and autumn flowering crocus, but distinguished Wild Saffron (Crocus) from Meadow Saffron ([[Colchicum]]). He described eleven forms. Some of his specimens were obtained from [[Carolus Clusius|Clusius]].{{sfn|Gerard|1597}}{{sfn|Kerndorff et al|2016}} In the following century, [[John Parkinson (botanist)|John Parkinson]] in a more detailed account was more careful to include separate chapters for ''Colchicum'', with the common name of meadow saffron, from ''Crocus'' or saffron. Parkinson (1656) states that there are "divers sorts of saffrons" describing 27 spring flowering plants and 4 autumn flowering ones, pointing out that only one of those was the true saffron crocus, which he called ''Crocus verus sativus autumnalis''.{{sfn|Parkinson|1656}} Similar accounts are found in continental European herbals, including those of [[Matthias de l'Obel|l'Obel]] in [[Flanders]] (1576){{sfn|l'Obel|1576}} and [[Basilius Besler|Besler]]'s ''[[Hortus Eystettensis]]'' in [[Bavaria]] (1613).{{sfn|Besler|1640}}

The genus ''Crocus'' was first formally described by [[Carl Linnaeus|Linnaeus]] in 1753, with three [[taxa]], and two species, [[Crocus sativus|''C. sativus'']] ([[type species]]), [[var.]] ''officinalis'' (now treated as a synonym of ''C. sativus'') and var. ''vernus'' (now [[Crocus vernus|''C. vernus'']]) and ''C. bulbocodium'' (now ''[[Romulea bulbocodium]]''). Thus Linnaeus recognised two taxa that are accepted as separate species in modern classifications, one vernal and one autumnal crocus, but incorrectly assumed they were only varieties of a single species, while his second species was actually from a closely related genus that was only recognised later (1772).{{sfn|Maratti|1772}} However, a subsequent re-examination of Linnaeus's specimens suggested the presence of several different species that he did not recognise as being separate.{{sfn|Peruzzi et al|2013}} [[Linnaeus' system]], based on sexual characteristics, ''Crocus'' was classified as Triandra Monogynia (Three [[stamen]]s, Single [[Gynoecium|pistil]]).{{sfn|Linnaeus|1753}} Linnaeus's system was supplanted by the "natural" system which used a [[hierarchy]] of [[taxonomic ranks]] based on weighting of the importance of structural characteristics of the plant. [[Antoine Laurent de Jussieu|Jussieu]]  (1789) placed the genus Crocus in his ''Ordo'' ([[Family (biology)|family]]) Irides or ''Les iris'', as a member of the class ''Stamina epigyna'' (stamens inserted above the ovary) as part of the [[monocotyledon]]s, the first level of the division of the [[flowering plant]]s.{{sfn|Jussieu|1789}} 
[[File:Linnaeus crocus.jpg|thumb|upright|center|[[Carl Linnaeus|Linnaeus]]'s description of ''Crocus'' 1753|alt=Page from Linnaeus' 1753 work describing Crocus ]]
One of the first monographs of the genus appeared in 1809, by [[Adrian Hardy Haworth|Haworth]],{{sfn|Haworth|1820}} followed in 1829 by that of [[Joseph Sabine|Sabine]],{{sfn|Sabine|1830}}{{sfn|Kerndorff et al|2016}} and [[William Herbert (botanist)|Herbert]] in 1847.{{sfn|Herbert|1847}} In 1853, [[John Lindley|Lindley]] continued the placement of ''Crocus'' as one of 53 genera in [[Iridaceae]], which he included in a higher order of monocotyledons, the Narcissales.{{sfn|Lindley|1853|p=161}} [[John Gilbert Baker|Baker]] published a monograph on the genus in 1874, adopting a very different schema to that of Herbert.{{sfn|Baker|1874}} In 1883, [[Bentham & Hooker system|Bentham and Hooker]] described the Irideae (Iridaceae) as having more than 700 species, and divided it into 3 tribes and further into subtribes. [[Tribe (biology)|Tribe]] Sysyrinchieae as having 2 subtribes, including Ixieae. The latter was [[Circumscription (taxonomy)|circumscribed]] with four genera, ''Crocus'', ''[[Syringodea]]'', ''Galaxia'' (''[[Moraea]]'') and ''[[Romulea]]''.{{sfn|Bentham|Hooker|1883|p=693}} This circumscription has remained stable since, with the exception of ''Moraea'' which properly belongs in a separate tribe. The most influential monograph of the nineteenth century was that of [[George Maw|Maw]] (1886), which forms the basis of modern understanding of the genus. Maw built on the work of Herbert, rejecting Baker's classification.{{sfn|Maw|1886|p=22}} The availability of molecular phylogenetic methods in the late twentieth century has shown that the Iridaceae properly belong within the order [[Asparagales]].{{sfn|APG I|1998}}

=== Botanical illustration ===

The scientific study of the genus in the late eighteenth century was accompanied by detailed descriptions with [[Botanical illustration]]s, such as those of [[William Curtis]] (1787) and [[John Sims (taxonomist)|Sims]] (1803),{{sfn|Sims|1803}} that appeared in [[Curtis's Botanical Magazine]], with illustrations by [[Sydenham Edwards]].{{sfn|Davies|2001}} Other illustrations are found in [[monograph]]s such as those of [[Adrian Hardy Haworth|Haworth]] (1809){{sfn|Haworth|1820}} and [[Joseph Sabine|Sabine]] (1830), illustrated by [[Charles John Robertson]].{{sfn|Sabine|1830}} The largest collection is found in the most comprehensive monograph, that of Maw (1886).{{sfn|Maw|1886}} Other sources include the portfolios of plates, such as the survey of the plants of France by [[Amédée Masclef|Masclef]] (1891). At that time only ''C. sativus'' and ''C. vernus'' were included in the [[Flora]] of France.{{sfn|Masclef|1890–1893}} 
{{
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| image1=Crocus vernus Botanical Magazine 45.jpg|caption1=''Crocus''<br />[[Curtis's Botanical Magazine]] 1787|alt1=Illustration of a yellow crocus angustifolius from 1787| width1={{#expr: (150 * 1900 /1425) round 0}}
| image2=Crocus-angustifolius.jpg|caption2=''[[Crocus angustifolius|C. angustifolius]]''<br />[[Curtis's Botanical Magazine]] 1803|alt2=Illustration of yellow Crocus angustifolius from 1803| width2={{#expr: (150 * 1900 /1425) round 0}}
| image3=Crocus stellaris Haworth.jpg|caption3=''Crocus luteus''<br />[[Adrian Hardy Haworth|A Haworth]] 1809|alt3=Illustration of yellow Crocus luteus from 1820| width3={{#expr: (150 * 1900 /1425) round 0}}
| image4=Crocus bouquet Sabine.jpg|caption4=Crocus bouquet of 19 species<br />[[Joseph Sabine|Sabine]] 1830|alt4=Bouquet of 19 different crocus species from 1830| width4={{#expr: (150 * 1900 /1425) round 0}}
| image5=Crocus iridiflorus Maw.jpg|caption5=''C. iridiflorus''<br />[[George Maw|Maw]] 1886|alt5=Hand painted lithograph of Crocus iridiflorus from 1886| width5={{#expr: (150 * 1900 /1425) round 0}}
}}

=== Phylogeny ===

The genus ''Crocus'' belongs to the [[Monocotyledon|monocot]] [[Family (biology)|family]] [[Iridaceae]] (iris family), specifically the large subfamily [[Crocoideae]]. Within that subfamily, crocus is placed on the [[Tribe (biology)|tribe]], Ixieae (synonym Croceae),{{efn|[[Peter Goldblatt|Goldblatt]] originally described this tribe in 2006,{{sfn|Goldblatt et al|2006}} but in 2011 renamed it Ixieae, having discovered that this name had precedence{{sfn|Goldblatt|Manning|2011}}}} one of five. The Ixieae are then subdivided into subtribes, with the genera ''Crocus'', ''[[Romulea]]'' and ''[[Syringodea]]'' forming subtribe Romuleinae. The Romuleinae have been characterised within the Ixieae by progressively reduced aerial stems.{{sfn|Goldblatt et al|1998|p=312}}  solitary flowers on the stem branches and woody tunics on the corms. They also often have divided style branches. However, ''Crocus'' corm tunics are fibrous and membranous rather than woody as in ''Syringodea.'' Also, ''Crocus'' has a ridged and often keeled abaxial leaf surface, while that of ''Syringodea'' is rounded, and the midline adaxial translucency of ''Crocus'' is lacking in ''Syringodea''. ''[[Romulea]]'' is principally distinguished from the other two genera by generally having aerial stems or at least an ovary at ground level, compared with the other acaulescent genera, other differences include unifacial rather than bifacial leaves and the pollen structure.{{sfn|Phillips|Rix|1989|p=31}}{{sfn|Goldblatt et al|1998|p=312}}

Within the Romuleinae, ''Crocus'' is a [[sister group]] to ''Syringodea'', the two genera forming a sister group to ''Romulea''.{{sfn|Goldblatt et al|2006}}{{sfn|Petersen et al|2008}}{{sfn|Harpke et al|2013}}

=== Subdivision ===

The genus Crocus consists of about 200 accepted species, which continue to increase, and has undergone a large number of [[Taxonomy (biology)|taxonomic]] classifications.{{sfn|Kerndorff et al|2016}} The genus has often been divided into [[Section (botany)|sections]], beginning with that of Haworth (1809){{sfn|Haworth|1820}} who described two sections based on the presence or absence of hairs in the throat of the flower, while Sabine was the first to realise the importance of the presence or absence of a basal spathe (prophyll) in dividing the genus into two sections,{{sfn|Sabine|1830}} a practice followed by Herbert.{{sfn|Herbert|1847}} However, Sabine's practice of using trinomials for [[variety (botany)|varieties]] such as ''C. sulphureus concolor'' is no longer accepted, although Herbert somewhat similarly used varieties and subvarieties, e.g. ''C. vernus'' var.1 ''Communis'' subvar. 1. ''Obovatus''. Herbert also used geographical distribution as a basis of classification.{{sfn|Kerndorff et al|2016}} By the late 19th century [[George Maw|Maw]] (1886),{{sfn|Maw|1886}} following Herbert, subdivided the genus into two divisions, the ''Involucrati'' and the ''Nudiflori'', and then further divided it into six sections and lastly by flowering times (spring or autumn). Although rejecting the concept of subvarieties, he placed even more emphasis on geography.{{sfn|Mathew|1986}}{{sfn|Harpke et al|2013}}{{sfn|Rix|2008}}{{sfn|Kerndorff et al|2016}}

The most widely accepted system, that proposed by [[Brian Mathew]] in 1982{{sfn|Mathew|1983}} was based on Maw's system, but with less emphasis on flowering times. This mainly depended on three character states: 
* the presence or absence of a prophyll (a basal [[spathe]]);
* the aspect of the [[Carpel|style]];
* the [[corm]] tunic. 
and included 81 species, however, one of these, ''Crocus medius'' was later recognized as a [[Synonym (taxonomy)|synonym]] of ''[[Crocus nudiflorus]]''.{{sfn|Harpke et al|2013}}{{sfn|Petersen et al|2008}}

The genus, as described by Mathew, consisted of two subgenera, ''Crocirus'' (monotypic for ''[[Crocus banaticus]]'') and ''Crocus'' including the remainder of the species, based on whether the [[anthers]] were introrse or extrorse ([[Dehiscence (botany)|dehiscence]] directed towards or away from centre of flower) respectively. Subgenus ''Crocus'' was then divided into two sections, ''Crocus'' and ''Nudiscapus'', based on the presence or absence of the prophyll. Each section was then further divided into six [[Series (botany)|series]] of ''Crocus'' and nine of ''Nudiscapus''. These series were defined by the division of the style, the corm tunic, flowering time, leaf structure, presence of a [[bracteole]] and anther colour. Mathew also introduced the concept of [[subspecies]], including 50 in all, by giving similar but different [[Form (botany)|forms]] subspecies status if geographically separated, resulting in about 140 distinct taxa.{{sfn|Harpke et al|2013}} The seven species and ten subspecies discovered since then have been integrated into revisions of this classification, though new species continue to be described,{{sfn|Raca et al|2020}}{{sfn|Ciftci et al|2020}}{{sfn|Randelovic et al|2012}}{{sfn|Petersen et al|2008}} leading to estimates of at least 200 species.{{sfn|Harpke et al|2015}}{{sfn|Kerndorff et al|2016}}

==== Speciation ====

Crocus populations have extremely high infra-specific variability with a very diverse spectrum of morphological and phenotypical varieties, while many individual specimens from different species may closely resemble each other. Based on such morphological differences between isolated populations many new species have been named, but without a definition of new species based on molecular and/or karyological information, species can not be confirmed, creating difficulties in determining [[speciation]] and hence the exact number of species.{{sfn|Harpke et al|2016}}{{sfn|Roma-Marzio et al|2018}} The situation is even more complex once [[Hybridisation (biology)|hybridisation]] (combination of taxa) and [[introgression]] (transfer of genetic material) are considered.{{sfn|Harrison|Larson|2014}}{{sfn|Kerndorff et al|2016}}

==== Molecular phylogeny ====

The availability of [[molecular phylogeny]] methods revealed problems with the traditional systems based on [[Morphology (biology)|morphology]] alone. The first analysis of the complete genus was carried out by Mathew and colleagues in 2008 using [[nucleotide sequences]] from [[plastid]] regions. In particular, the DNA data suggest there are no grounds for isolating ''C. banaticus'' in its own subgenus ''Crociris'', though it is a unique species in the genus. Because it has a prophyll at the base of the pedicel, it therefore would fall within section ''Crocus'', although its exact relationship to the rest of the subgenus remains unclear.{{sfn|Petersen et al|2008}}

Of the 15 series in the Mathew scheme, only seven were [[monophyletic]], and in particular the largest series, ''Biflori'' and ''Reticulati'', which include a third of all species, were non-monophyletic. Another anomalous species, ''C. baytopiorum'', should now be placed in a series of its own, series ''Baytopi''. ''C. gargaricus'' subsp. ''herbertii'' has been raised to species status, as ''C. herbertii''. The autumn-flowering ''C. longiflorus'', the [[type species]] of series ''Longiflori'' (long regarded by Mathew as "a disparate assemblage"), appeared to lie within series ''Verni''. In addition, the position of ''C. malyi'' was currently unclear.{{sfn|Petersen et al|2008}}

DNA analysis and morphological studies suggest further that series ''Reticulati'', ''Biflori'' and ''Speciosi'' are "probably inseparable", ''C. adanensis'' and ''C. caspius'' should probably be removed from ''Biflori'', ''C. adanensis'' falls in a clade with ''C. paschei'' as a sister group to the species of series ''Flavi'' and ''C. caspius'' appears to be sister to the species of series ''Orientales''.{{sfn|Petersen et al|2008}}{{sfn|Harpke et al|2013}}

The study showed "no support for a system of sections as currently defined", although, despite the many inconsistencies between Mathew's 1982 classification and the current hypothesis, "the main assignment of species to the sections and series of that system is actually supported". The authors state, "further studies are required before any firm decisions about a hierarchical system of classification can be considered" and conclude "future re-classification is likely to involve all infrageneric levels, subgenera, sections and series".{{sfn|Mathew et al|2009}} A further study, using the [[internal transcribed spacer]] region (ITS) of the nuclear ribosomal DNA (rDNA), together with a [[chloroplast]] marker, broadly confirmed these findings.{{sfn|Harpke et al|2013}}

''Crocus'' forms a monophyletic [[clade]], with a basal [[polytomy]] of four subclades. The first clade (A) corresponding to section ''Crocus'', but including ''C. sieberi'' and several closely related species (originally included in section ''Nudiscapus'' series ''Reticulati''). The remaining three clades (B-D) include all the remaining species of section ''Nudiscapus''. Of these, B and C are small, corresponding to series ''Orientales'' and ''Carpetani'' respectively, with all remaining series in the large D clade. The exception is ''C. caspius'', originally in series ''Biflori'', which [[Segregate (taxonomy)|segregates]] in clade B. Thus, although division of the genus into two sections is well supported, no single morphological character defines these two groups. The ''C. sieberi'' group are assumed to have lost their prophyll secondarily. Of the series, eight could be shown to be monophyletic; ''Crocus'', ''Kotschyani'' and ''Scardici'' (section ''Crocus'') and ''Aleppici'', ''Carpetani'', ''Laevigati'', ''Orientalis'' and ''Speciosi'' (section ''Nudiscapus''). Flowering season did not correspond to molecular groupings and nor did any of the previously used morphological characteristics, indicating a high degree of [[homoplasy]], in which traits are gained or lost independently in different lineages. The remainder of the series could not be supported as natural groupings. Mathew's concept of subspecies status within ''C. biflorus'' could not be supported, each being considered a separate species, resulting in the genus having at least 150 species.{{sfn|Harpke et al|2013}}

A more detailed molecular and morphological study of series ''Verni'' (section ''Crocus'') allowed it to be better characterised and circumscribed, as well as the closely related series ''Longiflori''. Series ''Verni'' ''sensu'' Mathew was found to consist of two groups, the first being ''C. vernus'' ''sensu'' Mathew and the other consisting of ''C. etruscus'', ''ilvensis'', ''kosaninii'' and ''longiflorus''. The taxonomic status of ''C. vernus'' had been uncertain for some time, given the observation that the name was more properly applied to ''C. albiflorus'',{{sfn|Peruzzi et al|2013}} requiring a new designation of ''C. neapolitanus'' for those previously known as ''C. vernus''. Subsequently ''C. vernus'' was split into 5 separate species. The incorporation of ''C. longiflorus'' into series ''Verni'' resulted in making series ''Longiflori'' no longer a legitimate taxonomic unit.{{sfn|Harpke et al|2015}}

In section ''Nudiscapus'', series ''Reticulati'' was polyphyletic with species intermingled with series ''Biflori'' and ''Speciosi'', requiring a recircumscription, confining ''Reticulati'' to 8 species, to obtain monophyly.{{sfn|Harpke et al|2014}} Among the thereby displaced species, are a number of very closely related taxa, referred to as the ''Crocus sieberi'' aggregate, which has been proposed as a new series ''Sieberi''.{{sfn|Kerndorff et al|2016}} Other new series, such as ''Isauri'' and ''Lyciotauri'', continue to be created out of the ''Biflori'' series.{{sfn|Kerndorff et al|2014}}{{sfn|Kerndorff et al|2013}}

Mathew's circumscription of ''Crocus'' introduced the rank of subspecies, of which the largest number (14) were those of ''Crocus biflorus'' <small>[[Philip Miller|Miller]]</small>, the type species of series ''Biflori'', a number which continued to grow. Molecular methods identified these as a [[polyphyletic]] assemblage rather than closely related subordinate infraspecific taxa. This necessitated a complete taxonomic revision of series ''Biflori'', elevating each subspecies to species status.{{sfn|Harpke et al|2016}} A similar issue occurs with ''C. reticulatus'' ''sensu'' Mathew, who created two subspecies, resulting in 9 newly defined species.{{sfn|Harpke et al|2014}}

==== Sections and species ====
{{main|List of Crocus species}}
The classification of Brian Mathew (1982), as amended in 2009 divides the genus into two sections, further divided by series.{{sfn|Mathew et al|2009}} The number of series, continues to evolve. 
* Section ''Crocus'' <small>B.Mathew</small>
Species with a basal [[prophyll]]. [[Type species]] ''[[Crocus sativus|C. sativus]]'' <small>L.</small>
: 6 series
* Section ''Nudiscapus'' <small>B.Mathew</small>
Species without a basal prophyll. [[Type species]] ''[[Crocus reticulatus|C. reticulatus]]'' <small>[[Stev.]] ex [[Johann Friedrich Adam|Adams]]</small>
: 9 series

=== Similarly named species ===

Some crocus species, known as "autumn crocus", flower in late summer and autumn, during (autumnal) rains, after summer's heat and drought. The name '''autumn crocus''' is also often used as a common name for ''[[Colchicum]]'',{{sfn|Wyman|1986}} which is not a true crocus but in its own family ([[Colchicaceae]]) in the lily order [[Liliales]]. The plants are toxic, but have medicinal uses. ''Colchicum'' are also known as '''meadow saffron''', though true [[saffron]] is not toxic.{{sfn|GBIF|2022}} ''Crocus'' species have three stamens while ''Colchicum'' species have six;{{sfn|Armitage|2008|p=278}} crocus have one style, while ''Colchicum'' have three.{{sfn|Bowles|1985|p=154}}{{sfn|Mabberley|1997}}

Some [[Pulsatilla]] species are also called "prairie crocus" (previously ''[[Pulsatilla patens|Anemone patens]])'' or "wild crocus", but they belong to the buttercup family ([[Ranunculaceae]]).{{sfn|Runkel|Roosa|2009|p=7}}{{sfn|Skelly|1994}} Pulsatilla species, which are commonly called pasqueflowers, unlike crocuses have [[rhizome]]s, the foliage is covered with long soft hairs, and the flowers are produced on above-ground stems.{{sfn|Wencai | Bartholomew|2004}}{{sfn|Armitage|2008|p=843}}

=== Etymology ===

"Crocus", the name of the genus, is [[Late Middle English]] (late 14th century) and also denotes saffron. It is derived via Latin ''crocus ''from the [[Ancient Greek|Greek]] κρόκος (''krokos''),{{sfn|Liddell|Scott|1996a}} which is itself probably a [[loan word]] from a [[Semitic languages|Semitic language]], related to [[Hebrew language|Hebrew]] כרכום ''karkōm'',{{sfn|Pankhurst|Hyam|1995|p=134}} [[Aramaic language|Aramaic]] ܟܟܘܪܟܟܡܡܐ ''kurkama'', and [[Arabic language|Arabic]] {{lang|ar|كركم}} ''kurkum'', meaning saffron (''Crocus sativus''), "saffron yellow" or [[turmeric]] (see ''[[Curcuma]]''), another yellow dye.{{sfn|OED|2022}} The word ultimately traces back to the [[Sanskrit]] ''kunkumam'' ({{lang|sa|कुङ्कुमं}}) for "saffron". The English name is a learned 16th-century adoption from the Latin ''safranum'', but Old English already had ''croh'' for saffron, introduced by the Romans.{{sfn|Maw|1886}}{{sfn|Harper|2022}}{{sfn|Sharifi|2010}}