Gagea

The genus contains geophytes that use bulbous parts to survive unfavorable conditions and quickly reproduce during favorable conditions. Gagea species have persistent tepals, and are generally smaller in size than other closely related genera in the Liliaceae family.^[10]

The genus has varied leaf morphology. However, it is common for them to have basal leaves, some of which are cauline. ^[10]

Some species have trichomes. These trichomes differ in their morphology. For instance, G. alberti and G. jensii have dendroid-type trichomes, but G. stepposa has glandular trichomes. It is also common for Gagea species to have amphistomatic stomata.^[11]

Gagea use two separate reproductive systems, insect pollination and asexual bulbil reproduction.^[12][13] There are two patterns of bulbil reproduction. In a more "continuous" mode, the plant "turns on" the ability to make bulbils, and continues to do so, only needing 2-10 millimeters cubed of total plant volume to begin vegetative reproduction. Once it reaches 100-300 millimeters cubed of volume, in some spcies, like G. lutea, the plant stops bulbil reproduction to begin expending energy towards a flowering phenophase. In some species, like G. spathacea, the plant never stops bulbil reproduction, and has no ability to reproduce sexually (through flowering). ^[12]

It is common for Gagea species begin flowering early into spring.^[13][14] Many Gagea are spring ephemerals, and need to complete their flowering cycles before tree cover re-emerges. By mid-spring to summer, these species will store themselves in bulbous parts underground in anticipation of the next flowering period.^[14]

During their flowering periods, species show different environmental adaptations based on their habitats. G. sect. Platayspermum Boiss live in more arid regions, where it is common for insects to feed upon any exposed fruits or seeds from flowering plants. Therefore, the sect. uses large, tough sepals to ward off insects attempting to consume its fruit when it is in its developing phase.^[10] Other sects, such as G. lutea, commonly emerge immediately after snowmelt.^[14] Unlike in more arid regions, these species will have greener sepals after the flower is fully open.^[10]

Polyploidy and hybridization, in the case of Gagea, have large impacts on its ability to undergo speciation, as evident in European species of the genus.^[13][15] Previous studies have shown that these two processes can significantly contribute to the process of speciation, while retaining fertility within a population.^[16] Gagea, therefore, has the ability to contain unique species such as G. spathacea, being a nonaploid that causes the plant to be limited in post-zygotic reproduction. The species has spread across Central Europe, the Caucasus, Sweden, Denmark, the Netherlands, and Belgium with little to no genetic differences due to its use of clonal reproduction. However, through polyploidy and hybridization events, it still retains the ability to undergo evolution. ^[15]

As of January 2014^[update], the World Checklist of Selected Plant Families recognizes over 200 species, including those previously assigned to Lloydia.^[17]