Heteroplacidium compactum

Heteroplacidium compactum
Conservation status
Vulnerable  (NatureServe) [1]
Scientific classification
Kingdom:	Fungi
Division:	Ascomycota
Class:	Eurotiomycetes
Order:	Verrucariales
Family:	Verrucariaceae
Genus:	Heteroplacidium
Species:	H. compactum
Binomial name
Heteroplacidium compactum (A.Massal.) Gueidan & Cl.Roux (2008)
Synonyms [2]
List Catapyrenium compactum(A.Massal.) R.Sant. (1984) Dermatocarpon compactum(A.Massal.) Lettau (1912) Endocarpon compactum(A.Massal.) Nyl. (1858) Endopyrenium compactum(A.Massal.) Körb. (1863) Placidium compactumA.Massal. (1856) Placocarpus compactus(A.Massal.) Trevis. (1860) Rhodocarpon compactum(A.Massal.) Lönnr. (1858) Verrucaria compacta(A.Massal.) Jatta (1900)

Heteroplacidium compactum is a species of areolate, crustose lichen in the family Verrucariaceae. It has a cosmopolitan distribution. It is a lichenicolous lichen, growing as a facultative parasite on other lichens, typically on non-calcareous rock. It has rod-shaped (bacilliform) conidia measuring 5–7  μm long, and ascospores that are 11–18 by 8–10 μm. ^[3] Heteroplacidium zamenhofianum is a closely related species distinguished by having perithecia situated in the algal layer, and smaller ascospores (14–16 by 6–7 μm) with a more narrow ellipsoid shape. ^[4]

The lichen was originally described in 1857 by Italian lichenologist Abramo Bartolommeo Massalongo as Placidium compactum. After having been shuffled to various genera in its taxonomic history, ^[2] it was transferred to Heteroplacidium in 2008 following molecular phylogenetic analysis of that genus. ^[5]

References

1. NatureServe. "Heteroplacidium compactum". NatureServe Explorer. Arlington, Virginia. Retrieved 5 July 2025.
2. "Synonymy. Current Name: Heteroplacidium compactum (A. Massal.) Gueidan & Cl. Roux, Bull. Inf. Ass. Franç. Lichén. 33(1): 25 (2008)". Species Fungorum . Retrieved 9 September 2022.
3. Prieto, María; AraGgón, Gregorio; Martínez, Isabel (2010). "The genus Catapyrenium s. lat. (Verrucariaceae) in the Iberian Peninsula and the Balearic Islands". The Lichenologist. 42 (6): 637–684. doi:10.1017/s0024282910000319.
4. Urbanavichus, Gennadii; Urbanavichene, Irina (2013). "New records of pyrenocarpous lichens from the NW Caucasus (Russia)". Herzogia. 26 (1): 123–129. doi:10.13158/heia.26.1.2013.123.
5. Roux, C. (2008). "Likenoj de Okcidenta Europo. Suplemento 4a : eltirajoj 2 (extraits 2). Korektendoj (errata)". Bulletin d'informations de l'Association française de lichénologie. 33 (1): 25.