Lilaeopsis schaffneriana var. recurva

Lilaeopsis schaffneriana var. recurva grows in perennial, shallow and slow-moving water. Such sites are rare in southeastern Arizona and northern Sonora, Mexico. Lilaeopsis is difficult to locate in the field, in part because it usually occurs with and resembles another small wetland species, Eleocharis charibea. Lilaeopsis has semisucculent leaves that are somewhat flexuous, whereas Eleocharis leaves are pithy, strictly straight and not at all succulent. The leaves of Lilaeopsis also appear to be a pale yellow-green compared to the darker green of most co-occurring herbaceous species.

Lilaeopsis schaffneriana var. recurva occurs in rivers, streams, springs, and cinegas, which are marshy or meadow-like wetlands surrounded by semiarid vegetation (USFWS 2017, Warren 1991).

Hendrickson and Minckley (1984) describe three different types of cienegas based on elevation: low, mid, and high elevation cienegas. Low elevation cienegas or subtropical marshes occur mostly along major perennial rivers below 3,000 feet. The low elevation Lileaopsis sites have experienced the most disturbance, both human and natural. Low elevation cienega habitats were probably river backwaters and floodplain seeps. These locations are very unstable, experiencing cycles of flooding and drying due to varying climatic patterns. Human influence including groundwater pumping and diversion of water for irrigation have eliminated perennial flow in most southeastern Arizona rivers. Perennial flow is essential for wetland formation.

Mid-elevation cienegas occur between 3,000-6,000 feet. This elevation range fits Hendrickson and Minckley's (1984) definition of true cienega habitat. Permanent water is available and a unique wetland community has developed at these sites (Warren 1991). Flooding potential is lower at these cienega sites because they have smaller drainage areas. Also, the gradients are gentler at these mid-elevation sites as opposed to the higher elevation cienegas.

High elevation cienegas occur at elevations over 6,000 feet. They are described by Hendrickson and Minckley (1984) as "marshy to bog-like alpine and cold temperate meadowland." They may form in surface depressions that fill with water or at stream headwaters. There are few potential sites for Lilaeopsis at these elevations because usually these higher sites are in canyons with stream gradients too steep to support cienega wetlands. Three high elevation sites of Lilaeopsis are known in the Huachuca Mountains. One is in upper Scotia Canyon and another in upper Garden Canyon.

The surrounding vegetation of the cienega communities varies with elevation. Willow (Salix spp.) and cottonwood (Populus spp.) trees, cattails, large reeds, bulrush (Scirpus spp.), and halophytes in nearby saline areas are typical of desert-scrub communities of the low elevation cienega sites. Rushes, grasses, fewer cattails, semiaquatic sedges, watercress (Nasturtium officinale), water pennywort (Hydrocoytle americana), halophytes in adjacent saline areas, and trees (not as common with willows being the most common) are the dominant species of the grassland/oak woodland habitat of mid-elevation cienegas. Finally, the high elevation community is conifer forest including cold-resistant sedges and rushes, semiaquatic and terrestrial grasses, and low, woody alder (Alnus spp.) and willow (Salix spp.) shrubs.

This taxon does not tolerate much competition with other herbaceous aquatic plants, but will quickly colonize habitat disturbed by scouring floods and persist there until interspecific plant competition becomes too great. In order for populations to expand, some plants must remain in areas that escape the effects of periodic floods (Rutman and Rorabaugh 1995).

Affolter (1985) observed flowering specimens from collections made in June and August and fruiting specimens from May and July through early September. Flowering at low frequency has also been observed from March through October. Although seeds from Lilaeopsis schaffneriana var. recurva appear to germinate easily, vegetative reproduction via rhizomatous spreading and dispersal of dislodged clumps is clearly important.

Seeds are believed to remain in the seedbank for 5 to 10 years, providing a means of reestablishment after drought (USFWS 2017). The buoyant seeds are dispersed by water.