Persoon described its fruiting bodies as gregarious (i.e. growing in groups but separate at the base), varying from simple to branching structures, predominantly whitish in colour with yellow to brownish tips.

The cosmopolitan distribution of Multiclavula mucida and its variability in appearance have led to a complex nomenclature and historical confusion with other species and genera.

He noted its autumnal appearance on decaying, moist tree trunks covered with a crust or green powder, sometimes extending over a wide area.

After its initial placement in Clavaria, it has been proposed for transfer to Typhula (by Elias Fries in 1827), Calocera (Richard Wettstein, 1886), Pistillaria (Julien Noël Costantin and Léon Marie Dufour, 1891), Lentaria (E. J. H. Corner, 1950), and Stichoclavaria (Eckehard Paechnatz, 1987).

Despite Corner's extensive literature compilation, he couldn't inspect many type specimens, leading to reliance on past reports for species reclassification.

Despite these differences, the species within Lentaria have been subdivided into two distinct groups, neither of which aligns with Corner's subgenera, which indicated the necessity for a new genus classification.

This consolidation and the unique aspects of C. mucida facilitated the establishment of Multiclavula as a distinct genus, addressing both phylogenetic and morphological disparities.

It protects the algae from UV light and desiccation, while ensuring close contact through a hyphal network that provides a continuous water and minerals supply.

The algal partners are encapsulated in tiny pockets of fungal tissue, yet they retain a loose, unstructured form, manifesting as a green granular crust where the fungus produces its fruiting bodies.

[10] David Arora, in his popular field guide Mushrooms Demystified, describes the edibility of these tiny and temporary fruit bodies as "utterly inconsequential".

[19] Multiclavula vernalis, while somewhat similar in appearance to M. mucida, is distinguished by its orange colour, its preference for growing on soil, and the presence of cystidia.

[9] Multiclavula coronilla, which grows on similar substrates, bears resemblance but can be differentiated by its shorter and simpler (unbranched) fruiting bodies, which are up to 1 cm tall, and its by its basidia, which have 6 to 8 sterigmata.

This small, whitish species, characterised by a broadened, flattened tip, typically grows on twigs, needles, and other types of debris, rather than amidst scum on rotting wood.

However, their ecological preferences differ; M. mucida mainly grows on decaying logs, while S. leucodontium typically inhabits terrestrial environments in lowland and sub-lowland forests.

[25] The discovery of M. mucida at unusually low elevations, specifically around 130 to 135 m (427 to 443 ft) above sea level in the Bienwald area of Rhineland-Palatinate, has prompted a reevaluation of its distribution and naming inconsistencies across different scientific literatures.

This expansion in its geographical range could be attributed to the establishment and maintenance of natural forest reserves, environments that foster the decay of thick logs and provide suitable habitats for the fungus.

[27] Historically, however, the species has faced declines due to intensive forestry and environmental pollution, such as soil acidification from sulfur dioxide emissions, which damage its natural habitats.