Ipheion
The flowering plant genus Ipheion (starflower, spring starflower) belongs to Allioideae, a subfamily of the family Amaryllidaceae. The World Checklist of Selected Plant Families no longer recognize the genus, regarding it as a synonym of "Tristagma", although The Plant List accepts two species. Description. They are small bulbous perennials with narrow grass-like leaves and honey-scented star-shaped flowers in spring, usually in shades of white or pale blue. The genus occurs naturally in Argentina, Uruguay, and southern Brazil, although "Ipheion uniflorum" has naturalized elsewhere. Taxonomy. History. The genus was originally described in 1836 by Constantine Samuel Rafinesque , based on "Ipheion uniflorum", separating it from "Milla uniflora" Graham (now "Tristagma"). The original description was unifloral inflorescences with white flowers, spathe formed by one bifid bract, staminal filaments independently fused to the perigonial tube and the fruit being a clavate trilocular capsule. The name then disappeared for more than a century and at various times the species have been included under other related genera ("Milla", "Tristagma", "Brodiaea" (including "Hookera"), "Leucocoryne", "Nothoscordum", "Triteleia" and "Beauverdia"). Several of these genera are now in a completely different but related family (Themidaceae). The closest of these genera to "Ipheion" is actually "Tristagma". For  instance in 1837, at the same time as Rafinesque's description, "Ipheion uniflorum" was described by John Lindley in the "Botanical Register" as "Triteleia uniflora" Lindl. (see illustration) In 1908, Beauverd placed "Ipheion uniflorum" in a new section of "Nothoscordum", "Nothoscordum" section "uniflora" Beauv. as "Nothoscordum uniflorum" Baker (without attributing Rafinesque), along with four other species. However the name "Ipheion" did not appear again until 1943. In that year Herter elevated "Nothoscordum" section "uniflora" to the rank of genus, as "Beauverdia". Later that same year Stearn pointed out that the name "Ipheion" had precedence and described the genus with nine  species under that name. There has been constant uncertainty as to the limits of the genus. At one stage it included 23 species in two sections, at other times it was completely absorbed into other genera such as "Tristagma". Those species with yellow flowers were returned to "Nothoscordum". In 1972 Guaglianone separated it again from "Tristagma" and divided it into two sections, "Hirtellum" and "Ipheion". At that time it consisted of eight species in Argentina, Uruguay, southern Brazil and central Chile. Familial circumscription. Lindley included "Ipheion" (as "Triteleia") under the family Liliaceae, a pattern that remained until 1926, when Hutchinson  moved parts of that family to Amaryllidaceae, as tribe Gilesieae, an arrangement that has largely persisted since. Phylogenetics. In 1996, a molecular phylogenetic study of the rbcL gene created the Gilliesioideae, as one of three subfamilies within Alliaceae. As phylogenetically constructed, Gilliesioideae (Gilliesioideae (Lindl.) Am., Botany: 134. 1832 - Gilliesieae Lindl. in Bot. Reg.: ad t. 992. 1826.) consisted of those New World Alliaceae not included in the other two subfamilies, which included both the former Gilliesieae together with "Ipheion", "Leucocoryne", "Nothoscordum", and "Tristagma". This is the circumscription which the Angiosperm Phylogeny Group (APG) accepted in the APG classification of 1998  and which later became known as Alliaceae "sensu stricto" ("s.s."). This construction of Gilliesioideae, implicitly recognised that it was composed of two groups or tribes, informally referred to as Ipheieae and Gilliesieae. The Ipheieae were actinomorphic, and included "Ipheion", "Nothoscordum", "Leucocoryne" "s.l." (including "Pabellonia" and "Stemmatium"). Further phylogenetic analysis revealed that "Ipheion" was not monophyletic but rather biphyletic with some species clustering with "Tristagma", and others with "Nothoscordum" (Fay 2006) although the division into sections was later supported. Research published in 2010 suggests that although related to genera such as "Tristagma" and "Nothoscordum", it is a distinct genus of 3  species. However, other sources do not recognize the genus, placing all the "Ipheion" species in "Tristagma". "Ipheion" section "Hirtellum" was raised to genus rank in 2014 under the older name of "Beauverdia", with four species found in Argentina, southern Brazil, and Uruguay. This corresponds to Group 3 of Sassone "et al." 2013. This leaves "Ipheion" section "Ipheion " representing the genus, but further work is required. This cluster (Group 2 in the cladistic analysis of Sassone "et al." 2013) which clusters with "Tristagma" may either be an independent genus, or a section of the latter genus. These are the three species  listed here. Species. Species formerly placed in this genus. Other species formerly placed in "Ipheion" have been transferred to "Beauverdia", "Nothoscordum" or "Tristagma": Uses. "Ipheion uniflorum" is widely used as an ornamental garden plant in the Americas, Africa, Australia and Europe.