Flora of North America species comparison

Oxalis debilis appears to be spreading rapidly in the United States. The species produces numerous bulblets in a basal cluster and apparently also can spread laterally by production of bulblets at the tips of filiform roots or rhizomes; it can form large, dense colonies. A. Lourteig (1980) noted that plants of this species occasionally fruit but consistently reproduce through abundant bulblets. They apparently are seed-sterile in North America.

Oxalis corymbosa and O. debilis were differentiated by A. Lourteig (2000) primarily by the distribution of oxalate deposits in the leaf lamina. In O. debilis, the dotlike deposits are crowded along the margins and absent to distinctly less abundant elsewhere. In O. corymbosa, the deposits are evenly distributed over the whole lamina. In their native range in South America, the two expressions are broadly sympatric and intermediates are common, as they are in the flora area. Intermediates have the oxalate dots along the margins as well as over the whole surface or sometimes mostly on the outer third of the blades, near the margins. There is no justification for formal recognition of two entities.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Collections of Oxalis latifolia from trans-Pecos Texas and eastern New Mexico were mostly identified by M. F. Denton (1973) as O. alpina and O. drummondii. Oxalis latifolia in the narrow sense (type from Campeche, Mexico), with somewhat angular leaflets, occurs in Mexico as far north as Veracruz, San Luis Potosí, and Tamaulipas. The northern populations tend to have more rounded leaflets and perhaps may be better identified by a different name, but they are neither O. alpina (with bulblet clusters) nor O. drummondii (with three-nerved bulb scales).

M. F. Denton (1973) observed that Oxalis latifolia probably consists of several races and perhaps hybrids with other species. A. Lourteig (2000) recognized four subspecies of O. latifolia. Her concept of subsp. latifolia restricted it to South America and the West Indies (even though the type was collected in Mexico); subsp. schraderiana (Kunth) Lourteig is entirely South American; and subsp. vespertilionis (Zuccarini) Lourteig occurs in montane Mexico south to Guatemala. She recognized subsp. galeottii (Turczaninow) Lourteig as occurring from Mexico into the United States. In contrast, most others have treated O. galeottii Turczaninow as a distinct species of central and southern Mexico, broadly sympatric with O. latifolia.

(Discussion copyrighted by Flora of North America; reprinted with permission.)