Gentianella microcalyx
Ann. Missouri Bot. Gard. 44: 246. 1957.
Herbs annual, 15–60 cm. Stems decumbent to erect, branched distally, often also at or near base. Leaves: basal often withered by flowering, larger leaves ± petiolate, blades elliptic to spatulate or oblanceolate, 10–25 × 2–8 mm; cauline blades cordate-ovate to lanceolate, 5–50 × 3–30 mm. Inflorescences terminal and often axillary umbelloid cymes; pedicels 3–25 mm. Flowers (4- or)5-merous; calyx 2–3(–5) mm, lobes triangular to oblong or elliptic, ± unequal, 1.5–3.5 mm; corolla yellowish white to pale rose-violet or pale violet-blue, occasionally with red-violet spots distally, narrowly funnelform to nearly salverform, 6–13 mm, lobes spreading, lanceolate-ovate, (2.5–)3–6.5 mm, apex obtuse to acute (in dried specimens sometimes appearing ± acuminate through inrolling), without adaxial scales or fringes; ovary short-stipitate.
Phenology: Flowering late summer–fall.
Habitat: Moist, rocky sites in ± open pine and pine-oak woods.
Elevation: 600–2100 m.
Distribution
Ariz., Mexico (Chihuahua, Coahuila, Durango, Sonora).
Discussion
Gentianella microcalyx is primarily of Mexican distribution, where its range extends to higher elevations than in the flora area, where it is known only from southern Arizona.
Selected References
None.