Linum sect. Linopsis

(Reichenbach) Engelmann

Smithsonian Contr. Knowl. 3(5): 25. 1852.

Basionym: Linopsis Reichenbach Handb. Nat. Pfl.-Syst., 306. 1837
Synonyms: Mesyniopsis W. A. Weber
Treatment appears in FNA Volume 12. Treatment on page 378. Mentioned on page 371, 373, 394, 395.
Revision as of 20:07, 27 May 2020 by imported>Volume Importer

Herbs or subshrubs, annual or perennial, rarely with woody caudex. Stems terete, ridged, or sulcate. Leaves alternate, opposite, or whorled; stipular glands present or absent; blade margins entire or glandular-toothed, sometimes ciliate. Flowers homostylous; sepals persistent or deciduous, margins scarious or not, glandular-toothed or not; petals yellow, sometimes with maroon at base; staminodia present or absent; styles distinct or connate nearly to apex; stigmas usually capitate, rarely linear. Capsules dehiscing into 10, 1-seeded segments or 5, 2-seeded segments; false septa incomplete to complete. Pollen tricolpate or multiporate.

Distribution

Nearly worldwide.

Discussion

Species ca. 85 (30 in the flora).

Key

1 Styles distinct. > 2
2 Stigmas linear [subsect. Halolinum]. Linum trigynum
2 Stigmas capitate [subsect. Linopsis]. > 3
3 Stipular glands present [ser. Linopsis]. > 4
4 Proximal leaves in whorls of 4. Linum schiedeanum
4 Proximal leaves opposite or alternate. > 5
5 Styles 2–3 mm; petals 4–6.5 mm; Florida. Linum arenicola
5 Styles 3–6.5 mm; petals 7–11 mm; New Mexico, Texas. Linum rupestre
3 Stipular glands absent. > 6
6 False septa incomplete, proximal margins ciliate. > 7
7 Capsules turbinate, 2–3 mm; anthers 0.5–1 mm; c, e United States [ser. Virginianum (in part)]. Linum intercursum
7 Capsules triangular-ovoid to broadly ovoid or ovoid-pyriform, 2.3–4 mm; anthers 1–2.5 mm; w United States [ser. Neomexicana]. > 8
8 Annuals, 15–60 cm; inflorescences thyrses; styles 1.5–3 mm; capsule apices obtuse. Linum neomexicanum
8 Perennials, 5–30 cm; inflorescences panicles or thyrses; styles 4–7 mm; capsule apices pointed. Linum kingii
6 False septa nearly complete, proximal margins sparsely or not ciliate [ser. Virginianum (in part)]. > 9
9 Capsules 1.3–2.3 mm, depressed-globose (broader than long) or globose, apices depressed. > 10
10 Margins of inner sepals usually glandular-toothed, rarely entire; mature capsule segments usually persistent on plant. Linum medium
10 Margins of inner sepals eglandular or with a few small sessile glands; mature capsule segments falling freely. > 11
11 Inflorescences corymbs; pedicels 1–10 mm; carpels flattened or ± concave abaxially. Linum virginianum
11 Inflorescences panicles; pedicels 0–4 mm; carpels convex abaxially. Linum striatum
9 Capsules 2–3.9 mm, either pyriform to ovoid or subglobose, apices abruptly short-pointed, obtuse, or 5-apiculate. > 12
12 Leaves mostly opposite; capsules subglobose, apices abruptly short-pointed. Linum westii
12 Leaves: proximal usually opposite, distal alternate, rarely all alternate; capsules pyriform to ovoid, apices obtuse or minutely 5-apiculate. > 13
13 Margins of inner sepals entire; capsules 3.4–3.9 mm; seeds 2.8–3 mm. Linum macrocarpum
13 Margins of inner sepals glandular-toothed; capsules 2–3.4 mm; seeds 1.6–2.5 mm. Linum floridanum
1 Styles connate [subsect. Rigida]. > 14
14 Capsules dehiscing into 10, 1-seeded segments; sepals persistent [ser. Sulcata]. > 15
15 Sepals (3.1–)3.6–5(–7.3) mm, apices acuminate. Linum sulcatum
15 Sepals 2.3–3.7 mm, apices acute. Linum harperi
14 Capsules dehiscing into 5, 2-seeded segments; sepals deciduous or persistent [ser. Rigida]. > 16
16 Sepal margins not glandular-toothed. > 17
17 Distal leaves and bracts not ciliate; capsule false septa entirely hyaline, or with cartilaginous portion very narrow, uniform, distal. Linum hudsonioides
17 Distal leaves and bracts sparsely ciliate; capsule false septa with cartilaginous portion conspicuously broader near base. Linum imbricatum
16 Sepal margins (some or all) glandular-toothed. > 18
18 Outer sepals ovate or obovate, margins undulate or crenate, with sessile gland near summit of each crenation. Linum alatum
18 Outer sepals linear, linear-lanceolate, lanceolate, or narrowly ovate, margins glandular-toothed. > 19
19 False septa incomplete, proximal margins terminating in loose fringe; sepals persistent. > 20
20 Styles connate to within 0.8–3 mm of apex; pedicels (5–)20–30(–60) mm; stipular glands absent. Linum subteres
20 Styles connate to within 0.2 mm of apex; pedicels 2–12 mm; stipular glands usually present. Linum vernale
19 False septa complete, proximal margins not terminating in loose fringe; sepals usually deciduous. > 21
21 Plants gray-puberulent throughout or puberulent or glabrescent in proximal 1/3. > 22
22 Herbs, annual or short-lived perennial, gray-puberulent throughout. Linum puberulum
22 Subshrubs, puberulent or glabrescent in proximal 1/3, otherwise glabrous. Linum allredii
21 Plants glabrous, glabrate, scabrous, or puberulent or hirsutulous at base. > 23
23 Sepals linear-lanceolate. > 24
24 Petals obovate; stamens 5–7 mm; styles 4.5–7 mm. Linum aristatum
24 Petals obcordate; stamens 4–5 mm; styles 3–4 mm. Linum lundellii
23 Sepals lanceolate to narrowly ovate. > 25
25 Stipular glands usually absent. > 26
26 Styles 2.5–4 mm, petals 6–11 mm. Linum compactum
26 Styles 3–11 mm, petals 10–18 mm. > 27
27 Petals coppery yellow or orange, red-lined or with short pale to deep brown-red zone at base; styles 5–11 mm; sepal apices sharply acute to acuminate; w, c North America. Linum rigidum
27 Petals orange-yellow throughout; styles 4–6 mm; sepal apices short-awned; s Florida. Linum carteri
25 Stipular glands usually present at least at some nodes. > 28
28 Styles 6–9.5 mm. > 29
29 Petals with prominent wine-colored band proximal to middle. Linum elongatum
29 Petals reddish below middle. Linum berlandieri
28 Styles 2–6 mm. > 30
30 Sepal apices aristate; petals yellow to yellow-orange throughout. Linum australe
30 Sepal apices acute to acuminate or short-awned; petals yellow to orange, sometimes with reddish base. > 31
31 Sepal apices short-awned; s Florida. Linum carteri
31 Sepal apices acute to acuminate; c United States. > 32
32 Stamens 4–5 mm. Linum lundellii
32 Stamens 6–8 mm. Linum rigidum