"Identity of three American species of Borreria (Rubiaceae): B. latifolia, B. flavovirens y B. poaya. New contributions to establish its delimitation: first chromosome counts, new synonyms and expansion of geographical distribution."

ELSA L. CABRAL; SANDRA V. SOBRADO; GRACIELA I. LAVIA

Xalapa, Veracruz, Mexico.

Conferencia; IV International Rubiaceae (Gentianales) Conference.; 2008

Organizing committee of the IV International Rubiaceae (Gentianales) Conference.

The genus Borreria G. Mey. belong to the tribe Spermacoceae. Since its original description, some species of this genus went through some changes regarding their true taxonomic delimitation, or were segregated or included in other taxa. One of the reasons would be the high number and variety of exomorphological and palynological characters. To deepen the discrepancies, many species have similar morphological aspect in the field and even more when they are herborized. That is why there are divergent views among specialists regarding the criteria for delimitating this genus’ species, as well as the genus itself, which some authors absorbed Borreria to Spermacoce. Since there are still pending studies on molecular phylogenetics of the American species of the genus, we consider that transferring all to Borreria species to Spermacoce is at least precipitated. It is commonly found in herbariums, erroneous names that increase confusion for the correct identification of these three related species: Borreria latifolia, B. flavovirens and B. poaya. This work presents exomorphological, palynological and cytological differences, as well as similarities among the three species. We also present the first chromosome counts for the three taxa. The geographical distribution of B. latifolia and B. poaya is expanded which are recognized as new records for three South American countries. New synonyms for these last two species are included.