Lentibulariaceae, the bladderwort family, is a family of carnivorous plants containing three genera: Genlisea, the corkscrew plants; Pinguicula, the butterworts; and Utricularia, the bladderworts.

The genera Polypompholyx (two species of pink petticoats or fairy aprons) and Biovularia were formerly regarded as fourth and fifth members of this family. Biovularia has been subsumed into Utricularia, and Polypompholyx has been relegated to a subgenus of Utricularia. Placement of the family was previously in the Scrophulariales, which has been merged with Lamiales in the Angiosperm Phylogeny Group system.

Lentibulariaceae - Utricularia humboldtii

Evolution

Carnivory in plants appears to have evolved independently in four major angiosperm lineages and five orders: Poales, Caryophyllales, Oxalidales, Ericales, and Lamiales.

One common trait found in several Lamiales families that may have led to carnivory is the secretion of proteinase mucilage through leaf surfaces. This mucilage is generally used to prevent insect predation by trapping and degrading potentially harmful insects. Interestingly, some research suggests these glands can quite easily shift their function from secretion to absorption. This shift may have first occurred in the most recent common ancestor (MRCA) of the Lentibulariaceae, introducing absorptive glands that provided additional macronutrients through trapped insects. The additional source of nutrients may have increased fitness of plants growing in low-nutrient habitats which eventually caused an embrace of carnivory. Further mapping of traits also suggests the MRCA was terrestrial and possessed a basal rosette composed of flat leaves and a primary root.

References

• Ellison, A. and Gotelli, N. (2009). "Energetics and the evolution of carnivorous plants-Darwin's 'most wonderful plants in the world'". Journal of Experimental Botany 60: 19–42. (abstract here).
• Jobson, Richard W., Playford, Julia, Cameron, Kenneth M. and Albert, Victor A. (2003). "Molecular Phylogenetics of Lentibulariaceae Inferred from Plastid rps16 Intron and trnL-F DNA Sequences: Implications for Character Evolution and Biogeography". Systematic Botany 28: 157–171. (abstract here).
• K. Müller, T. Borsch, L. Legendre, S. Porembski, I. Theisen and W. Barthlott (2004). "Evolution of Carnivory in Lentibulariaceae and the Lamiales". Plant Biology (Stuttgart) 6 (4): 477–490. doi:10.1055/s-2004-817909. PMID 15248131. (abstract here).