Solanum americanum Mill.

Family: Solanaceae

Pertinent Synonyms & Notes (particularly those used in California; go to GRIN for other synonyms)

Solanum caribaeum Dunal, S. nodiflorum Jacq.

Pertinent Common Names (particularly those used in California; go to GRIN for other common names)

American black nightshade

Primary Disseminule Types

fruit (not likely to be dispersed directly to grape bunches), seed

Description (diagnostics are in brown)

Fruit a berry with numerous seeds, globose, shiny, dark green or brownish-black to purplish-black, 4–9 mm in diameter, rarely contains stone cells, deciduous.

Seed ± obovate in outline, typically notched along margin where hilum occurs, pointy at one end of hilum, strongly compressed, cross-section narrowly elliptic to fusiform, 0.8–1.6 mm long x 1–1.2 mm wide x 0.3–0.5 mm thick. Surface semiglossy, may be particularly dull or rough when dried bits of the mucilaginous envelope remain; otherwise, surface is reticulate-pitted, with the sinuous cell walls forming a maze of minute undulating ridges (may also have striations or appressed hair-like or scale-like cell wall structures on top of the reticulations and interspaces), nearly white or yellowish to orangish-brown.

Hilum marginal, in notch, linear to narrowly elliptic, whitish (lighter than testa), (0.2)0.4–0.6 mm long.

Similar Species

Compare to Similar Species of Solanum and Similar Species of Lycium & Physalis.

Risk Assessment (codes in yellow or red indicate cause for concern; assessments are current as of mid-2011; click AUQP, NZBORIC, or NZBPI for access to the most recent versions of these databases and possible assessment changes)