Boquila is a monotypic genus of flowering plants in the family Lardizabalaceae, native to temperate forests of central and southern Chile and Argentina. The sole species is Boquila trifoliolata Decne., known as pilpil, voqui, voquicillo, voquillo, voqui blanco in Chile. It grows vines that wrap around host plants, mimicking the host’s leaves in a phenomenon called mimetic polymorphism. It bears an edible fruit. This species has been shown to be capable of mimicking the leaves of its supporting trees. Ernesto Gianoli said "Boquila’s leaves are extraordinarily diverse. The biggest ones can be 10 times bigger than the smallest, and they can vary from very light to very dark. In around three-quarters of cases, they’re similar to the closest leaf from another tree, matching it in size, area, length of stalk, angle, and color. Boquila’s leaves can even grow a spiny tip when, and only when, it climbs onto a shrub with spine-tipped leaves." Without any nearby host leaves to influence them, the normal leaves of the B. Trifoliolata are relatively short and light green leaves with rounded edges. The Boquila, unlike other plants capable of mimicry, does not require physical contact to match its host.
Mimicry
Boquila trifoliolata is a unique species of plant because of its ability to mimic its leaves to the leaves of the hosts that are supporting them, a phenomenon called mimetic polymorphism. The B. trifoliolata adapted their climbing behavior to be protected from ground herbivores and the mimicry behavior as a protection against leaf herbivores. B. trifoliolata is distinct in comparison to other plants that can mimic, like the Australian Mistletoe, because it is not limited to mimicking a single host and also is not a parasite to the host tree. An individual B. trifoliolata vine can mimic multiple foliage closest in proximity to it. Their mimicking behavior was discovered by researchers Ernesto Gianoli and Fernando Carrasco-Urra. They carried out observations and measurements in a rainforest located at Puyehue National Park in southern Chile. They sampled 12 different species of host trees with 45 total individual B. trifoliolata vines that had climbed these trees. The two closest leaves in proximity between a pair of the 45 vine-trees were measured, 11 different traits in total: angle, thickness, petiole length, leaflet petiole length, leaflet angle, maximum width, maximum length, area, perimeter, area/perimeter, and color. Usage of a generalized linear model showed that 9 of the 11 traits demonstrated mimicry by the vine to its host tree. Gianoli et al. also sampled more individuals that were prostrated, that grew on leafless tree trunks, and more individuals that have climbed on the 8 most common host species. To analyze these samples, the researchers used multivariate analysis of variance. They found that the prostrate individuals were not different from the leafless-host vines, but that they were different for 7 of the 8 common-host vine leaves. They also concluded that the leafless-host vines were different for 6 of the 8 common-host vines. Currently, there is no known mechanism for how B. trifoliolata is able to mimic host leaves so well, but Gianoli proposes two possible mechanisms. One hypothesis is that volatile organic compounds emitted from host plant leaves induce a phenotypically change in closeby B. trifoliolata leaves. By receiving different host signals into its system, it is able to create specific signals and hormones in its tissues to regulate gene transcription of leaf morphology and developmental pathways for leaf differentiation. The other hypothesis is that there could be horizontal gene transfer between the host and B. trifoliolata. A study also by Gianoli et al. indicated that this leaf mimicry led to lower leaf herbivory rates. Climbing vines had no difference in herbivory compared to supporting host tree leaves but had much lower herbivory compared to prostrated, unsupported B. trifoliolata individuals. The highest amount of herbivory was on B. trifoliolata vines that climbed onto leafless hosts.
