Abstract Detail

Systematics Section

Guo, Jinyan [1], Wilson, Carol [2].

Are sepal crests phylogenetically informative in Iris.

Crested irises account for more than one fifth of the approximately 270 species in the genus Iris and are distributed across three subgenera, Limniris, Nepalensis, and Scorpiris. An elaborated ridge that is parallel and perpendicular to the lamina of the sepal distinguishes crested species. In these species, crests are morphologically diverse, mostly because of ridge elaborations. Subgenus Limniris section Lophiris species were historically grouped together and called the "crested iris" based on their shared characters of a sepal crest that is often relatively large, conspicuous, and brightly colored and the presence of rhizomes. All of the crested species in subgenera Nepalensis and Limniris and about 30% of the species in Scorpiris were sampled. Phylogenetic analyses were based on matK, trnK, trnL-trnF, rpoB-trnC, psbJ-petA and rpl32-trnL sequence data and structural studies used light and SEM microscopy.Our preliminary results show that section Lophiris is not monophyletic and that crests evolved independently at least six times in Iris. A core crested clade was resolved, which consists of two eastern Asian section Lophiris lineages and species from subgenera Scorpiris and Nepalensis. Five species currently assigned to section Lophiris represent three additional independent lineages while two species within subgenus Limniris section Limniris series Chinensis represent the other two independent crest origins. Although the presence of a sepal crest is homoplastic and has multiple independent origins in Iris, macro- and micro-morphological studies of mature sepal crests from each lineage showed that this character is phylogenetically informative.

Broader Impacts:

1 - Rancho Santa Ana Botanic Garden/Claremont Graduate University, Botany, 1500 North College Ave., Claremont, CA, 91711, USA
2 - Rancho Santa Ana Botanic Garden, 1500 North College Avenue, Claremont, CA, 91711-3157, USA

Keywords:
Iris
phylogenetics
sepal morphology.

Presentation Type: Oral Paper:Papers for Sections
Session: 35
Location: Lindell C/Chase Park Plaza
Date: Tuesday, July 12th, 2011
Time: 4:00 PM
Number: 35010
Abstract ID:512