Gayophytum diffusum
Gayophytum heterozygum
diffuse groundsmoke, spreading groundsmoke
zig zag gayophytum, zigzag groundsmoke
erect, branched or unbranched near base, much branched distally, usually with 1 or 2 nodes between branches, distal branching dichotomous or lateral branches shortened, 5–60 cm.
erect, usually unbranched near base, branched at each of several nodes proximal to first flower, less branched distally, branching dichotomous, 15–80 cm.
reduced distally, 10–60 × 1–5 mm;
petiole 0–10 mm;
blade very narrowly lanceolate.
much reduced distally, 15–60 × 1–5 mm;
petiole 0–10 mm;
blade narrowly lanceolate to sublinear.
with flowers arising usually as proximally as first 1–20 nodes from base.
with flowers arising usually as proximally as first 10–20 nodes from base.
sepals 0.9–3(–5) mm, reflexed singly or in pairs;
petals 1.2–5(–7) mm;
pollen 90–100% fertile;
stigma hemispheric to subglobose, exserted beyond anthers of longer stamens or surrounded by them at anthesis.
sepals 1–1.8 mm, reflexed singly or in pairs;
petals 2–3(–4) mm;
pollen ca. 50% fertile;
stigma hemispheric to subglobose, surrounded by anthers at anthesis.
ascending to reflexed, subterete, 3–15 × 1–1.5 mm, with inconspicuous or conspicuous constrictions between seeds, valve margins somewhat undulate, all valves free from septum after dehiscence, septum straight or sinuous;
pedicel 2–10(–15) mm, usually shorter than capsule.
ascending or reflexed, terete to ± flattened, 6–15 × 0.8–1.1 mm, with conspicuous irregular constrictions between seeds, valve margins undulate, all valves free from septum after dehiscence, septum sinuous;
pedicel (2–)3–12 mm.
(3–)6–18, all or most developing, arranged ± parallel to septum and in alternating pattern between locules, crowded, overlapping, often appearing to form 2 irregular rows in each locule, or well spaced, forming a single row in capsule, brown, sometimes mottled with gray, 1–1.6 × 0.5–0.8 mm, glabrous or puberulent.
2–10, ca. 1/2 aborted, arranged± parallel to septum and in alternating pattern between locules, adjacent seeds not overlapping, irregularly well spaced from each, forming a single row in capsule, brown or gray mottled with brown, 1.4–2 × 0.6–0.8 mm, glabrous or puberulent.
= 28.
= 14.
Gayophytum diffusum
Gayophytum heterozygum
Subspecies 2 (2 in the flora).
Gayophytumdiffusum consists of a diverse assemblage of tetraploid populations, some of which are similar to every known diploid species except G. humile. The combination of characteristics of at least five diploid species in various ways suggests that the complex is derived from several independently formed allopolyploids that subsequently hybridized and segregated to produce the observed diversity.
Populations of Gayophytum diffusum differ in breeding behavior. Populations with relatively large flowers and stigmas that extend beyond the anthers are obviously outcrossing, whereas most populations are small-flowered and modally self-pollinated. It is among the latter that the greatest morphological diversity is found. Often two or more morphologically different, apparently true-breeding strains can be found growing together. In such a variable complex, recognition of infraspecific taxa becomes arbitrary. In this treatment the striking morphological differences associated with breeding behavior have been used as a basis for subspecies recognition. At some localities the two subspecies intergrade.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Gayophytum heterozygum is the only species of Onagraceae outside of Oenothera that is a permanent translocation heterozygote (PTH) (W. L. Wagner et al. 2007), in which the chromosomes form a ring of 14 at meiosis rather than the seven pairs characteristic of all other self-pollinating diploid species of the genus. As is true for other PTH species, G. heterozygum produces only about fifty percent fertile pollen and a correspondingly reduced number of fertile seeds. All other species have less than ten percent of the pollen sterile.
It is not clear whether one or two species were involved in the parentage of Gayophytum heterozygum (H. Lewis and J. Szweykowski 1964; L. B. Thien 1969). This species is morphologically intermediate between G. eriospermum and G. oligospermum and has been suggested by Lewis and Szweykowski to be a PTH species derived by hybridization between them, much like the PTH species in 17. Oenothera.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Petals 3–5(–7) mm; sepals 2–3(–5) mm; stigma usually exserted beyond anthers of longer stamens at anthesis. | subsp. diffusum |
1. Petals 1.2–3 mm; sepals 0.9–2 mm; stigma surrounded by anthers at anthesis. | subsp. parviflorum |
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
PNW Herbaria, Turner Photog. 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
- Local floras: CA, OR, WA
- Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria
- WildflowerSearch
- iNaturalist (observations)
- USDA Plants Database
- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
