Potential And Purported Plant Pollinators

The first is a paper in Austral Entomology co-authored with Brazilian colleagues escribing a new species of weevil associated with a species of Cecropia (also known as trumpet trees) in the high-elevation grasslands of the Cerrado biome in western Brazil. The lead author is Aline Lira (Universidade Federal Rural de Pernambuco, Recife), who just defended her PhD thesis in Brazil (co-advised by Bruno), and conducted research at the Field last year thanks to support from the Science and Scholarship Funding Committee. Cecropia trees are abundant in the Neotropics, especially in disturbed areas. Aline collected weevils from Cecropia in her hometown while visiting family, and found that they were a completely new species, which the team named Udeus cerradensis. Species of Udeus are generally rare in collections and their biology is poorly known, despite a high abundance in nature. The tree species in question, Cecropia saxatilis, shares many of the putative traits related to beetle and weevil pollination, and a species of Udeus has been previously implicated as a pollinator of Cecropia, thus the team wanted to test whether this was the case here. Direct observations and sticky traps failed to find evidence that U. cerradensis is attracted to female flowers, leading to the conclusion that it is unlikely to be a relevant pollinator of Cecropia saxatilis. The study also reports on predation of U. cerradensis larvae of by the wasps Synoeca surinama and Protopolybia sedula. Says Bruno of the study, “It is a really beautiful natural history work, showing that there is a lot to be discovered literally in one’s own backyard. It will lay a foundation for many evolutionary studies that are underway in our lab.”The other paper, published in Biotrophica, deals with potential palm pollinators in Ecuador. Co-authors include Jholaus Ayala González and María Cristina Peñuela Mora (Universidad Regional Amazónica Ikiam, Ecuador). The palms Prestoea acuminata and P. schultzeana are important components in the dynamics of the Andean–Amazon transition forest, and are used by local communities, but little is known about their strategies for reproductive dynamics. Accordingly, the researchers studied the diversity of flower visitors and pollinators of each species, the differences between their pistillate and staminate phases, and the species shared between them. The study was carried out in the Piedmont evergreen forest and the Napo low evergreen forest of Ecuador. The team collected 15 inflorescences of P. acuminata and nine of P. schultzeana, and then divided the flower visitors into morphospecies and counted, photographed and identified them to the best possible taxonomic level. Says Bruno: “Palms in this genus were generally thought to be pollinated by bees or maybe flies. But guess what, it is actually mostly beetles and flies!” They counted 10,123 flower visitors from 82 species in P. acuminata and 1,192 from 42 species in P. schultzeana. Based on abundance and frequency of species, and observations of pollen in the pistillate phase, they found six potential pollinators in P. acuminata (all Coleoptera—beetles), and five in P. schultzeana (three Coleoptera and two Diptera—flies). “Someone had to just do better observations than spending a few hours next to flowers with a sweeping net,” says Bruno. “And almost all of those pollinators are currently unknown species.” Jholaus will visit the Museum this fall to work with Bruno on identification tools for palm pollinators in Ecuador.
June 7. 2024