Haseltonia 17: 3–23. 2012 3 CLADISTIC ANALYSIS OF TRICHOCEREUS (CACTACEAE: CACTOIDEAE: TRICHOCereeae) BASED ON MORPHOLOGICAL DATA AND CHLOROPLAST DNA SEQUENCES SofÍA Albesiano1,2 1 Universidad Nacional de La Plata. Buenos Aires, Argentina; 2 Universidad Pedagógica y Tecnológica de Colombia. Tunja. email:
[email protected] TERESA TERRAZAS Instituto de Biología. Universidad Nacional Autónoma de México, México D.F. Dedicated to Omar Emilio Ferrari (1936-2010) Abstract: Trichocereus (Cactaceae: Cactoideae: Trichocereeae) is a South American genus primarily inhabiting arid and semiarid areas in the Andean region of Ecuador, Peru, Bolivia, Chile and Argentina. The phyloge- netic relationships of Trichocereus were examined on the basis of 39 exomorphological characters and chloro- plast DNA sequences trnL-F and rpl16 for 17 species of Trichocereus, including three other genera of the tribe Trichocereeae (Echinopsis, Lobivia, Setiechinopsis), two of Notocacteae (Eulychnia, Wigginsia) and one of the Hylocereeae (Harrisia). The simultaneous phylogenetic analysis of both morphological data and noncoding DNA sequence data recovered Trichocereus as monophyletic if two species of Harrisia are part of it. Moreover, the Trichocereus clade is supported by three synapomorphies: basitonic growth with prostrate branches, imbri- cate scales along the floral tube, and subglobose fruits. Resumen: Trichocereus (Cactaceae: Cactoideae: Trichocereeae) es un género sudamericano que habita principalmente las zonas áridas y semiáridas de la región andina de Ecuador, Perú, Bolivia, Chile y la Argentina. Las relaciones filogenéticas de Trichocereus fueron examinadas sobre la base de 39 caracteres exomorfológicos y secuencias de ADN del cloroplasto, trnL-F y rpl16 de 17 especies de Trichocereus, incluyendo otros tres géneros de la tribu Trichocereeae (Echinopsis, Lobivia, Setiechinopsis), dos de Notocacteae (Eulychnia, Wigginsia) y uno de Hylocereeae (Harrisia).