This contributes to significantly faster weathering rates in certain environments, impacts various materials from natural rocks to man-made Sekishu roof tiles, and involves key biomolecules identified for survival and biodeterioration, including compounds to withstand intense ultraviolet radiation.

The largest genus in the family, Lecidea, was once a loosely circumscribed wastebasket taxon containing hundreds of morphologically similar species with generally crustose thalli, photobiont-free apothecial margins and translucent, single-celled ascospores.

He noted their apothecia (fruiting bodies) to be initially somewhat concave, evolving over time into flat or convex forms that resemble small dishes or patellae, each bordered by a distinct margin.

However, his proposed families (Koerberiellaceae, Lecidomataceae, Mycobilimbiaceae, and Porpidiaceae) have since been folded into Lecidiaceae;[1] later research showed that ascus structure is not a consistent taxonomic character.

[7] This finding was corroborated in 2006 by Miadłikowska and colleagues, who further showed that the family ought to be reclassified from the order Lecanorales to an uncertain (incertae sedis) provisional placement in the subclass Lecanoromycetidae.

[12] In this cases, sensu stricto in the sense of Hertel means saxicolous lichens with certain anatomical characters, such as excipulum, paraphyses and apical ascus structures.

[17] These organisms establish a symbiotic relationship primarily with green algae (chlorococcoid photobionts), and in some instances (such as in the genus Amygdalaria), they also engage with cyanobacteria within specialised structures called cephalodia.

The reproductive structures (ascomata) of these lichens are typically apothecia, which can either sit prominently on the surface (sessile) or be partially embedded (immersed) within the thallus.

[18] The structure and position of the ascocarp in Cyclohymenia epilithica appear to be unique among Lecideaceae: this lichen has a central sterile column surrounded by a ring-shaped hymenium.

The main distinctions between Lecidea and Lecidella include Lecidella's typically grey, granular thallus with black, blue-black, or white-grey lower thallus; reproductive structures such as soredia, isidia, and blastidia; common presence of conidiomata; Lecanora-type asci; paraphyses that are not fused and easily dispersed; and secondary metabolites including xanthones, orcinol depsidones, β-orcinol depsides, and triterpenoids.

They found that the contact between the symbionts ranged from intracellular fungal invasion in the primitively organised thallus to a looser association of wall-to-wall attachment in the more highly differentiated growth forms.

[23] A subsequent investigation identified crystals of moolooite, a copper oxalate compound, within Lecidea inops found growing on chalcopyrite ore.

[18] The following list indicates the genus name, the taxonomic authority, year of publication, and the number of species:[26] In 2014, Alan Fryday and Hannes Hertel proposed to reduce the genera Labyrintha and Notolecidea to synonymy with Poeltidea and Poeltiaria respectively.

[53] Contrary to the typical habitats favoured by other North American species in the Lecideaceae, Cyclohymenia epilithica uniquely thrives in shaded environments in cool, moist, temperate climates.

In specific arctic alpine environments, surfaces colonized by these lichens weather at rates estimated to be 25–50 times faster than those caused by other natural processes.

[55] The weathering impact of Lecidea auriculata on the Little Ice Age moraines of the glacier Storbreen in Jotunheimen, central southern Norway, has been documented.

[56] Species of Lecidea have also been observed degrading a variety of substances including granite,[57] Magaliesberg quartzite,[58] serpentinized ultramafic rocks,[59] and volcanic andesite.

[60] Research on Lecidea tesselata, found on desert rocks in western North America, identified key biomolecules aiding survival and chemical biodeterioration using Raman spectroscopy.

Sekishu roof tiles are a traditional Japanese housing component that are covered with an opaque reddish brown glaze consisting of an alkali feldspar-type X-ray amorphous glass, a surface that is unlikely to be affected by normal chemical weathering.

[64][65] Two Lecideaceae species have been assessed for the global IUCN Red List: Lecidea mayeri (data deficient, 2023),[66] and Immersaria fuliginosa (vulnerable, 2020).

It faces several threats that could rapidly lead to its decline and potential extinction, primarily due to its very limited distribution across just two locations with a total area of occupancy of 8 km2 (3.1 sq mi).

The main threats include trampling by livestock, fires (both natural and anthropogenic), and the adverse effects of climatic changes, such as decreased summer rainfall and increased sunlight, which could negatively impact its survival.