Flower morphology and its relationshipwith the pollination system in the southern South American genus Jaborosa (Solanaceae)

IBAÑEZ, ANA CLARA; SÉRSIC, ALICIA NOEMÍ; MORÉ MARCELA

Drakensberg

Congreso; South African Association of Botanists (SAAB), 39th Annual Conference; 2013

South African Association of Botanists

Flower morphology has been considered an important factor in species isolation because of its dual impact on the attraction and mechanical fit with pollinators. In the present work we quantified the variation in floral shape amongst twelve species of the genus Jaborosa Juss. (Solanaceae) to assess whether this variation is spurred by pollinator’ shifts or is explained by their phylogenetic history. Floral morphology (i.e. corolla limb shape and disposition of stamen and pistil within the corolla) was studied using traditional and geometric morphometrics. Flower shape and pollinator guild were mapped onto a molecular phylogeny of the genus and ancestral states were reconstructed. Two major clades were recovered, one grouping species that clearly exhibit a sphingophilous syndrome and the second one grouping the species pollinated either by saprophilous flies or moths. Sphingophilous species showed salverform flowers with dissected petals whereas the clade grouping the remaining myophilous and phalaenophilous species showed a greater variation in flower morphology from rotate to urceolate and tubular flowers. Flower architecture determined that pollen was carried in the proboscis of long-tongued hawkmoths and moths and in a nototribic or pterotribic position by carrion flies. These results suggest that pollinator shifts either than phylogenetic ancestry would be responsible of the diversification of flower shapes and patterns of pollen removal/deposition within the genus Jaborosa.