They consist of a cylindrical stalk, widening at some distance below the surface into a hollow bulb-like utricle, and continuing as a hollow cylinder some further distance. At this point the stalk bifurcates into two furrowed spirals, between which the cylinder opening acts as the trap entrance. The furrows of the spiraled trap arms are lined with hairs pointing inward and toward the bifurcation. The hollow cylinder section leading from the bifurcation to the utricle is likewise lined with upward-pointing curved hairs. Some species produce two trap forms, one shorter and one longer, which probably target different prey groups. These corkscrew-like structures passively capture protozoa and other metazoan. Since these traps occur in soil, they are continuously stimulated due to the vast microfauna found in the soil. Due to continuous stimulation, the plant actively secretes digestive enzymes in order to aid with digestion to gain more nitrogen, phosphorus, and other minerals. Phosphatase has been detected in all types of glands, allowing for the breakdown of prey and uptake of phosphorus in low-nutrient soils. Although not completely understood, the oxygen concentration inside Genlisea traps is negligible. For this reason, it is thought that anoxic conditions could be the mechanisms in which prey are killed. At the same time, anaerobic bacteria survive. Taxonomy Twenty-nine species are currently recognised in the genus. Two varieties are also considered valid: G. aurea var. minor and the autonymous G. aurea var. aurea. Intraspecific determination depends almost wholly upon the inflorescence, particularly upon the indumentum. Genetic variation is an interesting area of attention as it has an incredible high rate of nucleotide substitution rates across nucleus, chloroplast, and mitochondria when compared to other angiosperms. Due to a mutation leading to changes in phenotypic traits found in the mitochondria, reactive oxygen species are produced which ultimately lead to DNA damage and further mutations. Botanical history The genus was discovered by Augustin François César Prouvençal de Saint-Hilaire, who in 1833 described four species: G. aurea, G. filiformis, G. pygmaea, and G. violacea. Genome size range The genus has a 25-fold range in genome size among its species and notably includes some of the smallest known plant genomes. For example, the genome of G. nigrocaulis is 86 Mbp (1C; 2n = 40) while that of its close relative G. hispidula (1C; 2n = 40) is 1550 Mbp, 18-fold larger. More than one genome size has been measured in G. aurea