Xerocrassa simulata

Xerocrassa simulata is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Geomitridae. It is endemic to southern Spain, specifically adapted to dry Mediterranean climates. Like other land snails, it undergoes a life cycle that includes egg laying, hatching of juveniles, shell development, and reproductive maturity as adults. These snails play a crucial role in their ecosystem by recycling nutrients and serving as prey for various predators, highlighting their ecological significance in their native habitat.

Distribution
This species is common in the deserts and semideserts of the levantine region. Morphology varies greatly with locality.

Life cycle
The size of the egg of this species is 2.6 × 2.1 mm.

Xerocrassa simulata : Diet, Mucus Production, and Effects on Biocrust CO2 Efflux
Xerocrassa simulata (XS) exhibits a dietary preference for plant litter, distinguishing it from other desert snail species that primarily consume biological soil crust (biocrusts). In laboratory conditions, XS produces approximately 0.5 ± 0.1 mg of mucus per mg of body mass daily. Despite its dietary preference, XS mucus significantly affects biocrust activity through its deposition. The mucus increased CO2 efflux in both cyanobacteria-dominated and lichen/moss-dominated biocrusts, with consistent effects across different biocrust types (Hedges d effect sizes ranging from 1.28 to 1.44). For cyanobacteria-dominated biocrusts, XS mucus enhanced CO2 efflux by 106% compared to controls. These findings suggest that XS mucus acts as a potent stimulator of biocrust activity, regardless of the snail's primary diet or the specific biocrust community composition