familyAraceae
genusCalla

Calla

Linnaeus

Sp. Pl. 2: 968. 1753; Gen. Pl. ed. 5; 414, 1754.

Common names: Water arum arum wild calla
Etymology: a plant name used by Pliny, perhaps from Greek kallos, beauty
Treatment appears in FNA Volume 22.

Herbs, wetland. Rhizomes horizontal. Leaves appearing before flowers, several, emergent, arising along rhizome, also clustered terminally; petiole 1.5–2 or more times as long as blade; blade bright green, simple, not peltate, ovate to nearly round, base cordate, apex short-acuminate to apiculate; lateral veins parallel. Inflorescences: peduncle erect, as long as or longer than petiole, apex not swollen; spathe white, often green or partially green abaxially, not enclosing spadix; spadix cylindric. Flowers all bisexual or distal ones staminate; perianth absent. Fruits not embedded in spadix, red. Seeds 4–9(–11), embedded in mucilage. x = 18.

Distribution

Circumboreal.

Discussion

Numerous cytogenetic studies have been conducted on Calla with both diploid (2n = 36) and apparently tetraploid (2n = 72) populations reported (see G. Petersen 1989). All counts from North American populations counted have a somatic number of 36 chromosomes.

Species 1.

Lower Taxa