Rhodolirium

''Rhodolirium'' is a small South American genus in the tribe Hippeastreae of the family Amaryllidaceae. Although originally described by Philippi in 1858 it has long remained buried in other taxa, principally ''Hippeastrum'' and more recently ''Rhodophiala''. Only in recent years has it been rehabilitated.

Restoring the genus was first proposed by Naranjo & Poggio (2000), and accepted by Ravenna in 2003, although he used the name '' Rhodolirion'', originally used by Baker (1878) in his very broad construction of ''Hippeastrum'' including both ''Rhodophiala'' and "''Rhodolirion''". He also renamed '' Rhodolirium andinum'' as ''Hippeastrum rhodolirion''. Later he elevated ''Rhodolirion'' to the status of subgenus, with ''H. rhodolirion'' (subsequently '' Rhodophiala rhodolirion'') as the type species . Subsequently the genus has been treated as part of ''Rhodophiala''.

Description

Flowers single or pluriflor, perigone infundibular (funnel shaped) with elongated floral tube. Paraperigonium, if present, has free segments. Stigma capitate.

Taxonomy

For early treatment of ''Rhodolirium'', see Taxonomy of Hippeastrum. The rehabilitation has yet (as of February 2016) to be recognised by the World Checklist of Selected Plant Families, but is by the Missouri Botanical Gardens, with six species. The ability to resolve phylogenetic relationships based solely on morphological data is limited in the Amaryllidaceae, necessitating the use of molecular methods in addition. In their study of the American amaryllidaceae, Meerow ''et al.'' (2000) noted that ''Rhodophiala'' was polyphyletic.

Subsequently Munoz ''et al.'' undertook a detailed study of ''Rhodophiala/Rhodolirium'' species and related genera and confirmed the genus as circumscribed was indeed polyphyletic with three species segregating as a sister group to '' Phycella'' which they proposed to resurrect as genus ''Rhodolirium'', while the remainder of the species segregated in a separate clade more closely associated with ''Hippeastrum'', which they proposed as ''Rhodophiala'' ''sensu stricto''. When the morphology of the two groups thus identified was examined they were distinguishable by ''Rodophiala'' having a trifid stigma compared to capitate for ''Rhodolirium'', by the nature of the paraperigon segments, and by their chromosome numbers (2n=18 for ''Rhodophiala'' and 16 for ''Rhodolirium'') and their chromosome symmetry. Both groups appeared to be monophyletic and their differences sufficient to justify separation into two distinct genera. ''Rhodophiala'' and ''Hippeastrum'' appeared sufficiently close to explain their treatment as a single genus in older classifications, but their separation was consistent with the study by Meerow et al.

The proposal to separate the two genera supports Ravenna's morphological studies, with '' Rhodolirium montanum'' (formerly ''Rhodophiala rhodolirion'') as the type species for the new genus. Subsequent phylogenetic analysis by Garcia et al. (2014) confirmed this distinction between the genera and proposed dividing Hipppeastrea into two subtribes, Hippeastrinae and Traubiinae, placing ''Rhodophiala'' in the first and ''Rhodolirium'' in the second.

Subdivision

Five to six species.
* '' Rhodolirium andicola'' (Poepp.) Ravenna syn. ''Rhodophiala andicola'' (Chile to Argentina ( Neuquén))
* '' Rhodolirium chilense'' (L'Hér.) Ravenna syn. ''Rhodophiala chilensis'' (Chile)
* '' Rhodolirium fulgens''
* '' Rhodolirium laetum'' (Phil.) Ravenna syn. ''Rhodophiala pratensis'' (Northern and Central Chile)
* '' Rhodolirium montanum'' Phil. syn. ''Rhodophiala rhodolirion'' (Chile to Argentina ( Mendoza))
* '' Rhodolirium speciosum'' (Herb.) Ravenna

Distribution and habitat

From northern Chile, in coastal vegetation zones to Osorno province in the south, at altitudes of 150–2500 m. Also in Argentina.

References

Bibliography

*
*
*
*
*
*
*
*
*
*
*

{{Taxonbar, from=Q22815112

Amaryllidoideae
Amaryllidaceae genera