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Phylogeny of the genus Iris |
Iris is a Northern Hemisphere genus with about 260 species. They have colorful flowers with nectary guides and leaves that typically form a basal fan. Their geophytic organs are diverse and may be rhizomes, stolons, bulbs and/or tuberous roots. Currently the genus is subdivided six subgenera and 12 sections. Within one of the sections, Limniris, there are 16 series recognized. While some Iris species are found in mesic environments, most occur in desert, semi-desert or dry, rocky, montane habitats.
I am using four nucleotide sequence regions (ndhF, matK, trnK and ITS) to explore relationships among Iris species. I have included about 140 species that represent all of the subgenera and sections currently recognized within the genus. My preliminary findings show that the two largest subgenera, Iris and Limniris do not form a single lineage but instead have more than one origin each. In addition, three other Iridaceae genera that each have a single species, Belamcanda, Pardanthopsis and Hermodactylus, belong within Iris. This work is an expansion of my earlier research that included about 50 Iris species and that is reported on this site under the heading Systematics: Phylogeny of the genus Iris based on DNA sequence data.
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