Brodiaea nana
| Brodiaea nana | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Brodiaea nana | ||||||||||||
| Hoover |
Brodiaea nana is a species of the genus Brodiaea in the asparagus family (Asparagaceae). This endemic occurs only in the western US state of California .
description
Vegetative characteristics
Brodiaea nana grows as a perennial herbaceous plant . Plant tubers are formed as persistence organs . One to six narrow leaves are produced per tuber during the growing season.
Generative characteristics
The flowering time in California is in the spring from April to May. The slender inflorescence stem is only 2 to 10 centimeters long. At the end of the inflorescence stem there is an open, golden inflorescence . The bracts also cases, this is still in bud during the inflorescence, not completely. There are also cover sheets . The flower stalk is up to 4 inches long.
The hermaphrodite flowers are radial symmetry and threefold. There are two circles, each with three bracts , which are fused at their base. The three outer bracts are 3 to 5 millimeters wide and slightly narrower than the inner three, which are 4 to 7 millimeters wide. The six purple bracts are fused into a jug-shaped, opaque flower tube with a length of 6 to 9 millimeters, which narrows slightly above the ovary and does not open until the fruit is ripe. The corolla is 16.5 to 26 millimeters long and the free part of the bracts is usually more than twice as long as the flower tube. The free part of the bracts is spread out at a length of 10.5 to 18 millimeters. In Brodiaea nana there are within the bracts and with these three sterile stamens grow together, i.e. staminodes that resemble small petals and each face the outer bracts. In the case of the white and 6 to 8.5 millimeters wide staminodes located near the stamens, the edges are half rolled up at the middle of their length and the upper end is notched. The three fertile stamens are located opposite the inner bracts and are also fused at the base of the envelope. The base of the 1 to 2 millimeter long stamens is narrow-winged, but has no appendages. The size and shape of the stamens and the structures at the base of the stamens are important determinants for the Brodiaea species. The 3 to 5 millimeter long anthers have raised rounded papillae on the underside . Three carpels are long to a 2.5 to 4.5 mm, three crests membered ovary grown. The stylus , 4 to 6.5 millimeters long, ends in a three-lobed scar .
The egg-shaped capsule fruits open in folds = loculicide. The seeds are black.
Chromosome set
The basic chromosome number is x = 6; there is diploidy with a chromosome number of 2n = 12.
Occurrence
Brodiaea nana occurs in central California. The evaluation of herbarium material showed in 2006 that Brodiaea nana occurs from Merced County to Chico, in Butte County . In addition, there are several disjoint locations over volcanic rocks that border Payne's Creek and Battle Creek and in northern Tehama County and southern Shasta County.
It thrives on the edge of episodic, ephemeral still waters in thin layers of soil above the bedrock at altitudes of 10 to 410 meters.
Systematics
Taxonomy
The first description of Brodiaea nails done in 1936 by Robert Francis Hoover in Leaflets of Western Botany , Volume 1, Issue 19, pages 225-226. For a long time this taxon as a synonym of Brodiaea minor or as a variety Brodiaea minor var. Nana (Hoover) Hoover in American Midland Naturalist , Volume 22, Issue 3, 1939, page 566. Niehaus 1971 separated the populations of the three species Brodiaea minor (Benth .) S.Watson , Brodiaea purdyi Eastwood and Brodiaea nana Hoover probably not correct. Therefore, in 2006, Robert E. Preston reactivated Brodiaea nana Hoover .
Justification for the independence of the species Brodiaea nana and Brodiaea minor
Morphological analyzes show that Brodiaea nana is a separate species and not a subspecies of Brodiaea minor . Cytological investigations also show that Brodiaea nana has species rank. The first description by Hoover in 1936 was on species rank, in 1939 he reduced the rank to a variety of Brodiaea minor , since he found intermediate forms between Brodiaea minor and Brodiaea nana in Sacramento County , without mentioning which plant parts were intermediate. The range of measurements of all flower parts overlap, but on average all flower parts in Brodiaea nana are smaller than in Brodiaea minor . It is noteworthy that in Brodiaea nana the forms of the staminodes, stamens and pistils differ consistently from Brodiaea minor . In the case of Brodiaea species, these flower characteristics are traditionally the most important defining characteristics and justification for differentiating the species.
Relationships of the Brodiaea species
The relationship of the Brodiaea species, especially between Brodiaea pallida , Brodiaea minor and Brodiaea nana , remains unclear in 2006. The origin of the different degrees of ploidy in the related species is still unclear in 2006.
A group of related species, perhaps with the rank of a section, are Brodiaea stellaris , Brodiaea insignis , Brodiaea pallida , Brodiaea minor and Brodiaea nana . Brodiaea pallida and Brodiaea nana are diploid with a base chromosome number of x = 6 and are similar in their flavonoid chemistry, and their flower morphology is similar. The areas of Brodiaea pallida and Brodiaea nana overlap.
Individual evidence
- ↑ a b c d Rafaël Govaerts (Ed.): Brodiaea nana. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Accessed January 1, 2020.
- ↑ a b c d e f g h Robert E. Preston: A reconsideration of Brodiaea minor (Benth.) S. Watson and Brodiaea purdyi Eastwood (Themidaceae), with the resurrection of Brodiaea nana Hoover. In: Madroño , Volume 53, Issue 1, 2006, pp. 46-54. JSTOR 41425633 doi : 10.3120 / 0024-9637 (2006) 53 [46: arobmb] 2.0.co; 2
- ↑ a b c d e f g h J. Chris Pires, Robert E. Preston: Brodiaea , 2012: Brodiaea nana data sheet in Jepson Flora Project (ed.): Jepson eFlora .
- ↑ Brodiaea nana at Tropicos.org. Missouri Botanical Garden, St. Louis, accessed January 1, 2020.