font settings and languages

Font Size: Large | Normal | Small
Font Face: Verdana | Geneva | Georgia
Languages:

Burmannia capitata

(Southern Bluethread)

Overview

[ Back to top ]

Interesting Facts

[ Back to top ]
 

Common Names

[ Back to top ]

Common Names in English:

Southern Bluethread, Cap Burmannia, Southern Burmannia

Description

[ Back to top ]

Family Burmanniaceae

Herbs, annual or perennial , mycotrophic and white or purplish, or autotrophic and green. Roots subterranean , mycorrhizal, filiform or stoutly terete . Stems monopodial, unbranched or with few branches, erect , slender; rhizomes present or absent. Leaves present or absent, cauline or basal, alternate, simple , sessile, often scalelike, margins entire; stipules absent. Inflorescences terminal cymes, sometimes appearing racemose or capitate, or flowers solitary; each flower subtended by scalelike floral bract. Flowers: tepals 6, partially or wholly connate , tube persistent or caducous in fruit, limb lobes 3 in 1 whorl or 6 in 2 whorls, greenish, purple, or white, sometimes blue-tinged, often ribbed or winged , throat with or without annulus; stamens 3 or 6, sessile or subsessile ; pollen sacs separated on appendaged connective or connective broadened and connate, forming ring proximal to annulus; pistil 1, ovary inferior, 1- or 3-locular; placentation parietal or axile ; ovules numerous ; style 1, 3-branched apically; stigmas 3. Fruits capsules, ovoid , obconic, or cup-shaped; dehiscence transverse , longitudinal by 3 valves , or irregular. Seeds numerous, minute.

Genera ca. 15, species ca. 125 (3 genera, 5 species in the flora ) : mostly tropical and subtropical , worldwide.

Although Burmanniaceae have traditionally been placed in the Orchidales, it has been suggested that the family may be more closely related to the Melanthiales (= Liliales in the broad sense, as traditionally circumscribed) (R. M. T. Dahlgren et al. 1985) . More recently, molecular and morphological studies by L. R. Caddick et al. (2000, 2000b) support placement of the family in the Dioscoreales .

Burmanniaceae traditionally have been characterized as saprophytic , but the life form is more accurately described as mycotrophic or myco-heterotrophic (J. R. Leake 1994) . Even the photosynthetic species have been shown to be endomycorrhizal (P. J. M. Maas et al. 1986b; C. E. Wood Jr. 1983) and have been described as hemisaprophytic. Saprophytism in the Burmanniaceae and other achlorophyllous families has been fully discussed by J. R. Leake (1994) .[1]

Genus Burmannia

Plants annual , autotrophic, at least partly green. Rhizomes absent. Roots filiform . Stems usually unbranched, green. Leaves cauline, sometimes basal, green, purplish, or pale , scalelike to linear . Inflorescences 2-25-flowered cymes or flowers solitary; floral bracts sometimes appearing imbricate if internodes of cyme rachis are very short; pedicels 0-1 mm. Flowers erect , 3-ribbed to 3-winged; perianth persistent in fruit; annulus absent; stamens 3, proximal to inner perianth lobes, sessile; ovary 3-locular; placentation axile . Capsules obovoid to ellipsoid , transversely dehiscent .

Species ca. 60 (3 in the flora ) : mostly tropical and subtropical , Western Hemisphere, Africa, Asia (China) .[2]

Physical Description

Species Burmannia capitata

Stems 3-24(-33) cm. Leaves: basal leaves 0-3, ± same size as cauline leaves; cauline leaves subulate-lanceolate, 2-8 × 0.3-1.2 mm. Inflorescences 2-25-flowered cymes, usually appearing capitate (rarely less contracted ), or occasionally flower solitary; cyme rachis usually absent, rarely to 6 mm; floral bracts subulate to lanceolate, 1.5-4 mm. Flowers 3-ribbed or slightly 3-winged, 2-6 mm; perianth cream-colored to white, sometimes tinged with blue or green; perianth tube (3- or) 6-lobed, to 0.8 mm wide; outer lobes usually incurved , triangular, 0.3-0.5 mm, margins involute ; inner lobes absent or linear to elliptic , to 0.3 mm; pedicel 0-1 mm. Capsules 1.5-3 mm. [source]

Chromosome counts of this species are not known from our region. A count of 2n = ca. 136 was reported for collections from Argentina. [source]

Habit: Forb/herb

Flowers: Bloom Period: July, August, September, October.

Habitat

Low woods , pond margins , savannas , bogs , swamps , ditches; 0--100 m [3].

Typically found at an altitude of 0 to 2,388 meters (0 to 7,835 feet).[4]

Biology

[ Back to top ]

Reproduction

Duration: Annual

Taxonomy

[ Back to top ]

Synonyms

Syst. Nat. 1: 107. 1791 • Vogelia capitata Walter Ex J. F. Gmelin

Notes

Publishing author : Mart. Publication : Nov. Gen. Sp. Pl. (Martius) i. 12

Name Status: Accepted Name .

Last scrutiny: 21-Jun-2005

Similar Species

[ Back to top ]

Members of the genus Burmannia

ZipcodeZoo has pages for 4 species, subspecies, varieties, forms, and cultivars in this genus:

B. biflora (Northern Bluethread) · B. capitata (Southern Bluethread) · B. flava (Fahkahatchee Bluethread) · B. ledermannii (Bluethread)

More Info

[ Back to top ]

Further Reading

[ Back to top ]

Notes

[ Back to top ]

Contributors

Data Sources

Accessed through GBIF Data Portal November 11, 2007:

Identifiers

Footnotes

  1. Deborah Q. Lewis "Burmanniaceae". in Flora of North America Vol. 26 Page 11, 12, 13, 14, 15, 17, 486. Oxford University Press. Online at EFloras.org. [back]
  2. "Burmannia". in Flora of North America Vol. 26 Page 487. Oxford University Press. Online at EFloras.org. [back]
  3. "Burmannia capitata". in Flora of North America Vol. 26 Page 487, 488. Oxford University Press. Online at EFloras.org. [back]
  4. Mean = 58.960 meters (193.438 feet), Standard Deviation = 636.060 based on 383 observations. Altitude information for each observation from British Oceanographic Data Centre. [back]
Last Revised: 7/15/2012