First report on generalized pollination systems in Melastomataceae for the Andean páramos

Abstract

Melastomataceae is a megadiverse family with records of transitions from specialized to generalized pollination systems for several species. These transitions are associated with the colonization of new, unpredictable and/or impoverished pollinator habitats or habitats where specialized pollinators are scarce (e.g., in highland environments). The bee species diversity is low in highlands. Therefore, autonomous breeding systems such as apomixis and self‐pollination emerge in these environments. In this paper, we studied the floral traits associated with the generalization of pollination systems and registered the floral visitors of two species in the Colombian Andes: Miconia cataractae and M. elaeoides. We investigated the breeding system of M. elaeoides. Both species presented small flowers, short anthers of medium pore size, and nectar‐producing stomata on the base of the anthers. Miconia cataractae produced an average of 1.62 μl nectar/flower, a sugar concentration of 6.78%, whereas M. elaeoides produced 0.09 μl nectar/flower, a sugar concentration of 6.13%. We recorded a wide diversity of pollinators for both species, mainly insects from the orders Hymenoptera and Diptera. Miconia elaeoides presented a mixed breeding system and was also capable of setting fruits by apomixis. We conclude that flower and anther morphology, combined with nectar production, thus represent convergent traits resulting in a generalist pollination system shared by M. cataractae and M. elaeoides. Here, we presented the first generalist pollination system recorded for Miconia (and the Melastomataceae) in the Andes, the first report for a species from the small‐pored section Amblyarrhena, and the first report for a species from the large‐pored section Cremanium in Colombia.

An evolutionary disruption of the buzz pollination syndrome in neotropical montane plants

“…In Miconia , the evolution of greater self pollination has likely led to flowers with shorter anthers, presumably lowering the pollen quantity of each flower. For instance, 80% of fruit set in Miconia elaeoides is from autonomous self pollination, and its anthers are shorter (1.6–2.9 mm long) (Manrique‐Valderrama et al, 2022)⁠. Conversely, the strictly outcrossing Miconia paucidens has larger anthers (4–5 mm long) (Goldenberg and Shepherd, 1998)⁠.…”

Pollination biology of a rare serpentine plant, Japonolirionosense (Petrosaviaceae)

“…The nectar of both Japonolirion and Petrosavia is exposed (Takahashi et al 1993, Rudall 2002, this study), making it easily accessible to flower visitors. The flower visitors of the two genera include insects such as ants, bees, flies, and parasitoid wasps, which are frequently found in other plant species with exposed nectar (Sigrist et al 2021, Manrique Valderrama et al 2022). Japonolirion and Petrosavia may, therefore, be adapted to pollination by insects that feed on exposed nectar.…”

Reproductive biology in Gomphichis valida Rchb. f. (Orchidaceae: Orchidoideae, Cranichidinae): Generalist pollination in a high‐Andean terrestrial orchid with long‐lived flowers

“…(Asteraceae) at the Paramos ecosystem (Fagua & Gonzalez, 2007), as well as the most frequent floral visitor of two species of Miconia Ruiz & Pav. (Melastomataceae) (Manrique Valderrama et al, 2022). In addition, there are reports of these bees visiting and pollinating flowers of Vaccinium meridionale Sw. (Ericaceae), a species popularly known as "agraz," with economic importance (Pinilla-Gallego & Nates-Parra, 2015) and other families (Alarc on et al, 2022;Pelayo et al, 2015).…”