Geocarpon minimum

Mackenzie

Torreya 14: 67. 1914.

Common names: Tiny tim
IllustratedEndemicConservation concern
Treatment appears in FNA Volume 5. Treatment on page 149.

Stems greenish brown or strongly suffused with red, 1–4 cm × 0.5 mm or less; proximal nodes 1–3 mm apart, internodes zigzag, distal nodes 5–10 mm apart. Leaf-blades 3–4 mm, margins somewhat involute. Inflorescence bracts connate, strongly red or purple-tinged, keeled, triangular, 2.5–3.5 mm, apex acute. Flowers funnelform-campanulate, 3–4 mm; sepal lobes ± erect to slightly spreading, subequal; ovary greenish, ca. 3 mm, apex narrow at anthesis, minutely glandular-toothed or retuse. Capsules opening along 3 wirelike valve margins. Seeds 0.3–0.5 mm.


Phenology: Flowering late winter–early spring.
Habitat: Sandstone glades and alkali barrens
Elevation: 100-300 m

Discussion

Of conservation concern.

Geocarpon minimum is known from fewer than 35 sites, about one-third of which have relatively large, vigorous populations. The species is listed as federally threatened. In Missouri, it is found only in shallow depressions in slightly tilted sandstone strata within sandstone glade plant communities. In Arkansas and Louisiana, it is found in saline-alkaline soils on the edge of highly localized, surficial concentrations of sodium and magnesium, locally known as “slick spots”; a similar “saline barren” hosts the recently discovered (2004) Texas population. These austere and nearly barren patches of mineral soil are scattered across savannalike formations classified as saline soil prairies.

Geocarpon minimum is in the Center for Plant Conservation’s National Collection of Endangered Plants.

Selected References

None.

Lower Taxa

None.
... more about "Geocarpon minimum"
Mark A. Nienaber +
Mackenzie +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Laciniate (?) +, Emarginate (?) +, Jagged (?) +, 2-fid (?) +  and Entire (?) +
reduced +
herbaceous +  and scarious +
Tiny tim +
dish--shaped +
expanded +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Ark. +, La. +, Mo. +  and Tex. +
100-300 m +
straight +  and curved +
central +  and peripheral +
inconspicuous +
unisexual +  and bisexual +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
stalked +  and simple +
Sandstone glades and alkali barrens +
reddish +  and green +
disc--shaped +  and dish +
purple-tinged +  and red +
triangular +  and keeled +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
connate +
swollen +
3 +  and 5 +
3 cm30 mm <br />0.03 m <br /> (?) +
crassinucellate +  and bitegmic +
campylotropous +
fugacious +
4 +  and 5 +
Flowering late winter–early spring. +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
muriculate +
compressed +, reniform +, elliptic +  and ovoid +
reddish +  and green +
persistent +
triangular-ovate +
1 cm10 mm <br />0.01 m <br /> (?) +
Illustrated +, Endemic +  and Conservation concern +
scale-like +
few-branched +  and simple +
suffused with red +  and greenish brown +
1cm;4cm +
spreading-ascending;erect +
less;0.5 +
[50 +  and 3 +
papillate +
distinct +
filiform +
0.3 cm3 mm <br />0.003 m <br /> (?) +
Geocarpon minimum +
Geocarpon +
species +
divided +
10 +  and 8 +
rhizomatous +  and taprooted +
winter-annual +  and annual +
pubescence of simple hairs or stalked glands +  and glabrous +
23 +, 17 +  and 19 +