Darwiniana, nueva serie
versión impresa ISSN 0011-6793
TAPIA-PASTRANA, Fernando; GOMEZ-ACEVEDO, Sandra; MERCADO-RUARO, Pedro y LINARES, José. New reports of chromosome numbers in Karwinskia (Rhamnaceae). Darwiniana [online]. 2009, vol.47, n.2, pp. 267-270. ISSN 0011-6793.
A cytogenetic analysis using surface spreading and air drying was performed to analyze the mitotic chromosomes of Karwinskia calderonii, K. parvifolia and K. subcordata. The results confirm a diploid number 2n = 24 and a basic number x = 12. All species showed a somatic complement characterized by small meta- and submetacentric chromosomes. The smallest pair of each complement carried a secondary constriction and a satellite. Morphological and numerical constancy in the chromosome complements agree with previous studies in other species of the genus. Results suggest some kind of nucleotypic differentiation related to geographic factors as latitude and altitude.
Palabras llave : Chromosomes; Karwinskia; Rhamnaceae.