Carex sect. Physoglochin

Dumortier

Fl. Belg., 145. 1827.

Synonyms: Carex sect. Dioicae (Tuckerman) Pax
Treatment appears in FNA Volume 23.

Plants loosely cespitose or not, rhizomatous; rhizomes yellowbrown, long [short or lacking], slender, not more than 1.4 mm wide, mostly without persistent scales. Culms brown at base. Leaves: basal sheaths not fibrous; sheath fronts membranous; blades filiform or V-shaped in cross-section when young, widest less than 1 mm wide, glabrous. Inflorescence a solitary spike; proximal bract absent; spikes unisexual or androgynous, ovoid to cylindric. Proximal pistillate scales with apex acute to acuminate or cuspidate. Perigynia appressed to usually spreading or reflexed at maturity, veined on abaxial face, veined or veinless on adaxial face, stipitate, mostly oblongovate [ovate to lanceolate], planoconvex or unequally biconvex in cross-section, almost leathery, base rounded to broadly cuneate, with spongy tissue, margins rounded [sharp], apex abruptly contracted to beak, glabrous; beak 0.5–1 mm, with abaxial suture, weakly and sparsely serrulate, obscurely bidentulate. Stigmas 2. Achenes biconvex, almost as large as bodies of perigynia; style deciduous.

Distribution

Arctic, boreal, and alpine regions of North America and Eurasia

Discussion

Species 4–6 (2 in the flora).

Carex sect. Physoglochin consists of six closely related taxa that are traditionally accepted as distinct species. The American-east Asian plant, C. gynocrates in the strict sense, is very closely related to C. dioica and has been treated as a major race of that species. Other species may be more morphologically distinct (e.g., C. davalliana Smith) or less so (e.g., C. redowskiana C. A. Meyer). Detailed studies of variation within and between species are needed.

Section Physoglochin was included in subg. Primocarex by G. Kükenthal (1909). Because of the close morphogical similarity and the readiness with which hybrids are formed with species of sections Foetidae and Glareosae, sect. Physoglochin is now placed in subg. Vignea by most authors (A. O. Chater 1980; T. V. Egorova 1999).

Selected References

None.

Key

1 Culms trigonous, distinctly furrowed, arising from cordlike rhizomes 0.5–1.4 mm in diam.; perigynia appressed to weakly spreading, plano-convex, gradually tapering to ± prominent, glabrous beak, beak 0.7–1 mm; chiefly Eurasian, extending to e Greenland. Carex parallela
1 Culms ± terete, scarcely furrowed, arising from threadlike rhizomes 0.3–0.8 mm in diam.; perigynia soon becoming widely spreading to reflexed, biconvex, abruptly contracted to short, glabrous or obscurely scabrid beak, beak 0.5 mm; transcontinental and including w Greenland. Carex gynocrates

"not undefined" is not a number.

... more about "Carex sect. Physoglochin"
biconvex +
Theodore S. Cochrane +
Dumortier +
shortened +
rounded +  and broadly cuneate +
bidentulate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
v--shaped +  and filiform +
0mm;20mm +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
scale-like +  and leaflike +
parallel +  and divergent +
terete +, rolled +  and plicate +
0mm +  and 1mm +
round +  and trigonous +
Arctic +, boreal +  and and alpine regions of North America and Eurasia +
open +, pistillate +  and staminate +
hypogynous +  and subtending +
biconvex +  and trigonous +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
basal +  and cauline +
with (1-)3-6(-30) bristles and/or scales +
stipitate +, veinless +  and veined +
appressed +  and usually spreading or reflexed +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
adventitious +
persistent +
basal +  and proximal +
2-keeled +
cylindric +
androgynous +  and unisexual +
ovoid;cylindric +
1 (?) +  and 3 (?) +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
deciduous +
2-3(-4)-fid +
Carex sect. Dioicae +
Carex sect. Physoglochin +
section +
plant +, not +  and cespitose +