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Title: Painting a picture of paintbrushes: using geometric morphometric analyses of Castilleja calyces to quantify diversity in the coastal California species complex
The California floristic province is home to more than 30% of all Castilleja species across the North American wildflower genus (family Orobanchaceae). While some of the approximately 200 species are distinct morphologically, the five species composing the coastal California Castilleja species complex exhibit overlapping morphologies and geographic ranges, which poses particular challenges for species identification. To determine species, current keys employ a combination of geography, leaves, and reproductive structures. The sepals, known collectively as the calyx, are modified leaves that protect the flower and have historically been one of several important traits for diagnosing species in the complex. In this project, we utilized geometric morphometrics to quantify and describe calyx shape for three calyces per individual of five individuals across seven species, including two outgroups (n = 84). While traditional morphometrics only capture linear variation, geometric morphometrics translate more complex elements of shape. Calyx outlines were created from field scans and analyzed with Procrustes-based geometric morphometrics using three landmarks, followed by elliptic Fourier analysis. The first principal component axis across all samples explained 43.8% of variation and emphasized the depths of the calyx clefts relative to each other. Several species overlap in the morphospace while others remain distinct, which suggests limited morphological differentiation of the calyx across species and may allow for variation in successful pollination. Future analyses will quantify morphological variation in other floral organs observed both within individuals and within species to comprehensively assess morphological variation in the complex.  more » « less
Award ID(s):
2243994
PAR ID:
10502228
Author(s) / Creator(s):
; ;
Publisher / Repository:
Society for the Advancement of Chicanos/Hispanics and Native Americans in Science - 2023 NDiSTEM
Date Published:
Format(s):
Medium: X
Location:
Portland, OR
Sponsoring Org:
National Science Foundation
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