Abstract Detail

Macroevolution

Kiel, Carrie [1], Tripp, Erin [2], Fisher, Amanda [3], McDade, Lucinda [1].

Is pollen involved too? Floral traits and pollinators in New World Justicia (Acanthaceae).

The plant family Acanthaceae is known for its remarkable diversity of pollen morphology. This is particularly evident among members of New World Justicia (ca. 400 spp): pollen aperture number ranges from two to eight and exine sculpturing is highly variable. New World Justicia also encompasses amazing variation in flower shape, size and color, along with diversity of anther and stigma morphology. We have previously shown that, among these plants, micro-structures of anthers and stigmas co-vary in patterns that are correlated with corolla morphology. These statistically distinct corolla shapes are consistent with pollination by particular subsets of animals. Here we report the first results from investigation of microstructures of pollen grains. We quantify the surface relief of pollen exine sculpturing using 3-D models produced from anaglyphs from scanning electron microscopy images. Flower color, shape, and size are widely understood to reflect adaptation to pollinators such that evolutionary changes in these traits can result in reproductive isolation and speciation. Emerging evidence from New World Justicia indicates that evolutionary changes in microscopic traits of reproductive structures including pollen may also contribute to reproductive isolation. We will examine these pollen traits taking an integrative and comparative approach that includes quantitative analysis of variation in pollen structures and phylogenomic data to test the hypothesis that exine sculpturing on pollen grains is linked to pollination syndromes in this remarkably diverse group.

1 -
2 - C105, Ramaley Hall, UCB350, Clare Small Building, Basement, Boulder, CO, 80309, United States
3 - California State University, Long Beach, Biological Sciences, Mail Stop 9502, 1250 Bellflower Blvd, Long Beach, CA, 90840, United States
4 - Rancho Santa Botanic Garden, Rancho Santa Ana Botanic Garden, 1500 N College Ave, CLAREMONT, CA, 91711, United States

Keywords:
macroevolution
pollen
Pollination
floral evolution
Acanthaceae.

Presentation Type: Oral Paper
Session: MACRO1, Macroevolution I
Location: Tucson B/Starr Pass
Date: Tuesday, July 30th, 2019
Time: 10:45 AM
Number: MACRO1010
Abstract ID:770
Candidate for Awards:None