Hawk-moth pollination and elaborate petals in Cucurbitaceae: The case of the Caribbean endemic Linnaeosicyos amara

Linnaeosicyos amara is a little known cucurbit endemic to the Caribbean island of Hispaniola. The species possesses conspicuously fringed petals which are known in just four other cucurbit genera and hypothesised to play a role in pollinator attraction. A population of flowering L. amara plants was observed for a total of 78 h, which revealed that Sphingid moths are the primary pollinators. Floral scent was dominated by the terpenoid (E)-β-ocimene. The elaborate petal fringes almost doubled the apparent diameter of L. amara flowers and the maximal extension of petal fringes was found to coincide with the peak visitation period of hawk-moths, with withering starting soon after. We conclude that petal fringes likely play a role in the visual attraction of hawk-moths by exploiting their preference for large flowers with deeply-divided petal margins, whilst limiting energy costs to the plant.