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<div>Vernonia eineta Griseb. and V. seorpioides (Lam.) Pers. (Asteraeeae, Vernonieae) are two&nbsp;closely related taxa which have been considered by different authors either the same species&nbsp;or two varieties of the same species or two different species. In the present study a detailed&nbsp;chromosome analysis was carried out in an attempt to clarify the status and relationships of these&nbsp;two taxa. The cytological study revealed that Vernonia eineta has 2n=60 chromosomes and a</div><div>karyotype formula composed of 36m + 16sm + St, whereas V. seorpioides presents 2n=66 and&nbsp;a karyotype with 34m + 20sm + 12t. Besides, V. eineta showed two chromosome pairs bearing&nbsp;satellites on the short arms, one m pair with linear satellite and one t pair with macrosatellite;&nbsp;while V. seorpioides presented one mchromosome pair carrying a linear satellite in the long armo&nbsp;In addition to the chromosome number, these species showed certain other karyotypic&nbsp;differences, mainly in theirformula, total chromosome length and asymmetry leve!. Chromosomal&nbsp;information here reported supports the specific status of both taxa. The presence of telocentric&nbsp;chromosomes in V. cincta and V. seorpioides would distinguish them from the remainder New&nbsp;World species of Vernoniawhich commonly have metacentric and submetacentric chromosomes.</div><div>The karyotypic differences between V. cincta and V. seorpioides may be explained by the&nbsp;occurrence of structural rearrangements such as centric fusions or traslocations. This hypothesis&nbsp;is well supported by the similar total karyotype length of both taxa and the higher mean&nbsp;chromosome length of V. cincta, which presents a lower number of telocentric chromosomes&nbsp;than V. seorpioides.</div>