Marcgravia evenia

Marcgravia evenia is a species of flowering vine in the family Marcgraviaceae. Within this family it belongs to the Galetae group, which is characterized by a long inflorescence axis and boat shaped nectaries. The plant is endemic to Cuba. The inflorescence of M. evenia is extraordinary. At the upper end of the pendant inflorescence  are several concave bracts set at an angle to reflect and focus  sonar pulses from bats, helping the bats to locate the flowers.. In the middle of the inflorescence is a discoid circle (or single-whorled  umbel) of about twenty tubular tetramerous flowers. Below these is a second set of bracts very different from the reflective  ones   These are modified into extrafloral nectaries which is why the bats are interested, and can be enlisted as pollinators. Inflorescences with two different kinds of bracts are quite rare. although the common poinsettia (Euphorbia pulcerima) is one such.

Bat ecology
Marcgravia evenia relies on Monophyllus, a Cuban nectar-feeding bat, for pollination. This plant has evolved bowl shaped leaves which act as reflectors for a bat's biosonar. This helps the bats to find the plants with greater ease and hence pollinate them with more frequency. The shape of the leaves also helps to guide the bats in locating the hidden feeders. The reflectors are convergent with those of a Bornean pitcher plant, Nepenthes hemsleyana, that attracts bats to its pitchers as roosting sites and uses bat guano as a source of nutrition.