Flora of North America species comparison

Canadian populations of Anagallis arvensis are primarily found in southern coastal regions and the lower Great Lakes. The species has been reported also from Alberta, Newfoundland, Prince Edward Island, Saint Pierre and Miquelon, Saskatchewan, and Minnesota; it is not established in those areas.

The flowers close on cloudy days and as evening approaches, hence the name weatherglass. P. E. Gibbs and S. Talavera (2001) found that Anagallis arvensis self-pollinates as the petals close.

This is the most variable species of Anagallis, with reddish flowers once thought to be common in more northerly latitudes and blue flowers in southern areas. There are numerous intermediate color forms. The blue form has been the source of confusion in the nomenclature of this taxon. Linnaeus described the blue form of A. arvensis as A. caerulea. Schreber used A. coerulea (note the spelling) as did Lamarck for a related taxon that is now included within A. foemina Miller. Subsequent authors submerged A. caerulea/coerulea into A. arvensis as a forma, variety, or subspecies, incorrectly crediting either Schreber or Lamarck. L. F. Ferguson (1972) distinguished A. foemina Miller (including Schreber’s A. coerulea), which consistently produces blue flowers, as a separate entity differing, in part, by petals having few to no marginal hairs, which, when present, have elongate terminal cells (in A. arvensis the petal margins have numerous gland-tipped, globose hairs), and by having flowering pedicels equaling or shorter than the subtending leaf.

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

The largest genera in Myrsinaceae are the tropical Myrsine (300 species), Ardisia (400–500 species), and Embelia Burman f. (130 species), and the temperate Lysimachia (ca. 160 species). No genera are endemic to the flora area; some species (in Lysimachia) have been introduced and become naturalized. Ardisia elliptica is introduced and has been named a Category I Invasive Species by the Florida Exotic Plant Pest Council (http://www.fleppc.org/list/07list_ctrfld.pdf).

Myrsinaceae is of limited economic value, mainly as ornamentals (some Anagallis, Ardisia, Lysimachia). Most taxa are pollinated by insects, particularly bees and flies, with nectar or pollen as rewards; some Lysimachia have oil-secreting hairs and are pollinated by oil-collecting bees (S. Vogel 1974+, vol. 2); selfing also occurs. Temperate seeds are dispersed by gravity, water, wind, or, possibly, ants or other ground-dwelling insects (B. Ståhl and A. A. Anderberg 2004).

As circumscribed here, Myrsinaceae are closely related to Primulaceae and Theophrastaceae. M. Källersjö et al. (2000) and B. Ståhl and A. A. Anderberg (2004) removed the nonrosette terrestrial members from Primulaceae and placed them in the Myrsinaceae (see further discussion under Primulaceae).

Additional evidence (A. A. Anderberg et al. 2007; L. Martins et al. 2003) indicates that Lysimachia is not monophyletic. Further, Glaux is now considered an apetalous member of Lysimachia (Anderberg et al.; Hao G. et al. 2004); Trientalis probably should be considered an extreme verticillate member of Lysimachia sect. Seleucia (Anderberg et al.; alluded to by J. D. Ray 1956); and some species of Anagallis are more closely related to Lysimachia (Anderberg et al.; M. Källersjö et al. 2000; Anderberg and B. Ståhl 1995) than to other members of Anagallis. More work is still needed to resolve these additional issues. Martins et al. presented nuclear rDNA evidence that Centunculus is basal within Lysimachieae and should not be included within Anagallis but this is not yet fully resolved. The phylogenetic position of Cyclamen, a scapose taxon, has not been resolved; Ståhl and Anderberg (2004) included it in this family because it shares developmental anatomy, leaf pigmentation, and other features. Our understanding of the family is clearly still in flux, and future taxonomic realignments at the familial and generic levels are to be expected.

Genera ca. 50, species ca. 1400 (5 genera, 32 species in the flora).

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