Utricularia are carnivorous plants which have small hollow vesicles as suction traps that work underwater by means of negative pressure and watertightness of the entrance for capturing small animal prey. Utricularia multifida and U. westonii have specific thick-walled traps, which are triangular in a transverse section but their functioning is unclear. Some authors suggest that the trap door in U. multifida acts as a simple valve without a suction trapping mechanism. Our main aim was to check the anatomical trap characters that are responsible for possible water outflow and maintaining negative pressure as main functional parts of the active trap suction mechanism in both species. Using different microscopic techniques, we investigated the ultrastructure of external trap glands, quadrifids, glands near the entrance (bifids, monofids), and also pavement epithelium. Quadrifids of both species have a similar structure to those known in other species from the genus, which possess the suction trap mechanism. Glands near the entrance in U. multifida and U. westonii , which are responsible for water pumping in other species, are typically developed as in other species in the genus and have pedestal cells which are transfer cells. The transfer cells also occur in glands of the pavement epithelium, which is again typically developed as in other species in the genus. Simple biophysical tests did not confirm reliably neither the negative underpressure formation in the traps nor the watertightness of the entrance in both species. Our anatomical results indirectly support the hypothesis that both species have suction traps like all other Utricularia species, but the biophysical data rather suggest a passive valve mechanism.
Genlisea hawkingii, which is a new species of Genlisea subgen. Tayloria (Lentibulariaceae) from cerrado in southwest Brazil, is described and illustrated. This species has been found in only one locality thus far, in the Serra da Canastra, which is located in the Delfinó polis municipality in Minas Gerais, Brazil. The new species is morphologically similar to Genlisea violacea and G. flexuosa, but differs from them in having a corolla with a conical and curved spur along with sepals with an acute apex and reproductive organs that only have glandular hairs. Moreover, it is similar to G. uncinata's curved spur. G. hawkingii is nested within the subgen. Tayloria clade as a sister group to all the other species of this subgenus. Therefore, both morphological and phylogenetic results strongly support G. hawkingii as a new species in the subgen. Tayloria.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.