Ranunculus glaberrimus var. ellipticus [Elliptical Buttercup]

[Andrea B.]

Blum, A.G. (2013) Ranunculus glaberrimus Hooker var. ellipticus (Greene) Greene (Ranunculaceae) Elliptical Buttercup. Flowers photographed in ultraviolet and visible light. http://www.ultraviol...tical-buttercup

 

Twin Pines, LaPlata County, Colorado, USA

28 March 2013

Wildflower

 

Synonyms:

• Early Buttercup
  
• Sagebrush Buttercup
  
• Ranunculus ellipticus Greene
  
• Ranunculus glaberrimus Hook. var. buddii B. Boivin
  

Comments:

Native to the western US and Canada. R.g. var. ellipticus is distinguished from R.g. var. glaberimmus, which does not grow in Colordo, by having a longer middle lobe on its 3-lobed stem leaves (bracts).

 

The glossy distal end of a buttercup petal is water repellant while the duller proximal portion is not. This is thought to be support for a rainwater pollination stragegy.⁽³⁾

 

Like most buttercups in UV, the Elliptical Buttercup is iridescent and shiny and features a UV-black central pattern with UV-bright petal tips. The foliage is also very UV-dark.

 

Reference:

1. Natural Resources Conservation Service (2013) Ranunculus glabberimus Plant Profile. US Department of Agriculture. http://plants.usda.g...ile?symbol=RAGL

2. Weber & Wittmann (2012) Ranunculus L, page 314. Colorado Flora: Western Slope, 4th Ed. The U. of Colo. Press, Boulder, CO.

3. Benson, Lyman (1962) Plant Taxonomy: Methods and Principles, Ronald Press, New York, NY

 

Equipment [Nikon D600-broadband + Nikon 105mm f/4.5 UV-Nikkor]

 

Visible Light [f/8 for 1/1250" @ ISO 200 in Sunlight with Baader UVIR-Block Filter]

 

Visible Light [f/7.1 for 1/800" @ ISO 200 in Sunlight with Baader UVIR-Block Filter]

 

Ultraviolet Light [f/8 for 1/160" @ ISO 400 with SB-14 UV-modified Flash and Baader UV-Pass Filter]

 

Ultraviolet Light [f/11 for 1/125" @ ISO 400 with SB-14 UV-modified Flash and Baader UV-Pass Filter]