Coreopsis sect. Gyrophyllum

Perennials. Leaves cauline, opposite; blades usually 3-foliolate, sometimes simple or ± pinnately lobed (with 5+ leaflets), leaflets simple or each with 2–9+ lobes, or blades not 3-foliolate (then often with 3(–5+) lobes). Calyculi of 5–12+ bractlets. Phyllaries 8. Ray florets 8, neuter; laminae yellow, ± oblong-elliptic to suborbiculate, broadest at or near middle, apices entire or 2–3-toothed. Disc florets 25–80+; corollas yellow or ± red-brown to purple, lobes 5; style-branch apices ± penicillate. Paleae usually linear to subulate, often distally dilated. Cypselae obovate to oblong, wings corky to chartaceous, entire, ± spreading, not ciliolate, faces glabrous, smooth; pappi 0 or (1–)2 cusps (0.1–0.5+ mm; shoulders of wings sometimes bristly, pappus-like). x = 13.

Distribution

Mostly c, e United States.

Discussion

Species 6 (6 in the flora).

E. B. Smith (Bot. Gaz. 136: 83. 1975) used a superfluous name, sect. Palmatae (F. Boynton) E. B. Smith [based on Coreopsis (unranked) Palmatae F. Boynton in J. K. Small, Man. S.E. Fl., 1446. 1933], for sect. Gyrophyllum.

Selected References

None.

Lower Taxa

Coreopsis delphiniifolia, Coreopsis major, Coreopsis palmata, Coreopsis pulchra, Coreopsis tripteris, Coreopsis verticillata

Key

1	Blades of leaves not 3-foliolate, most 3(–5+)-lobed	Coreopsis palmata
1	Blades of leaves usually 3-foliolate, leaflets simple or ± pinnately or ± pedately lobed	> 2
2	Petioles 5–45 mm	Coreopsis tripteris
2	Petioles 0–1 mm.	> 3
3	Leaf blades or leaflets seldom lobed, lance-ovate to lanceolate or lance-linear, 2–30 mm wide	> 4
3	Leaf blades or leaflets often lobed, ultimate lobes oblong to linear or filiform, 0.5–2.5 mm wide	> 5
4	Leaf blades or leaflets (4–)6–15(–30+) mm wide	Coreopsis major
4	Leaf blades or leaflets 2–7 mm wide	Coreopsis delphiniifolia
5	Internodes (± mid stem) 15–40(–60) mm; leaflets entire or each with 3–9+, ± linear to filiform lobes 5–25(–45+) × 0.5–1(–2) mm; disc corollas yellow	Coreopsis verticillata
5	Internodes (± mid stem) 8–12(–16) mm; leaflets entire or each with 2–5+, ± oblong to linear lobes 15–30+ × –1.5(–2.5+) mm; disc corollas yellow or purple	Coreopsis pulchra