Massalongiaceae is a small family of lichen-forming fungi in the order Peltigerales.[1] It has three genera and seven species.

Massalongiaceae
Massalongia carnosa in California, USA
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Fungi
Division: Ascomycota
Class: Lecanoromycetes
Order: Peltigerales
Family: Massalongiaceae
Wedin, P.M.Jørg. & E.Wiklund (2007)
Type genus
Massalongia
Körb. (1855)
Genera

Leptochidium
Massalongia
Polychidium

Species in this family have cyanobacteria as their primary symbiotic partner (cyanobiont), so they belong to the group known as "cyanobacterial lichens".

Taxonomy edit

The family was circumscribed by Mats Wedin, Per Magnus Jørgensen, and Elisabeth Wiklund in 2007. Molecular phylogenetic analysis showed that the three genera formed a well-supported monophyletic group that was distinct from other similar families in the Peltigerales.[2] The family was named after the type genus, Massalongia; the genus name honours Italian lichenologist Abramo Bartolommeo Massalongo (1824-1860).[3]

Massalongiaceae has a sister taxon relationship with the family Peltigeraceae, and these two families together form a clade that is sister to a clade containing the families Vahiellaceae and Koerberiaceae.[4] Previous phylogenetic studies had placed genus Massalongia in a group together with Peltigeraceae, Nephromataceae and Lobariaceae, although the relationships of Massalongia within this group were not precisely determined.[5][6]

Description edit

The thalli of Massalongiaceae lichens range in form from squamulose (scaley) to microfoliose (tiny and leafy) or microfruticose (tiny and bushy). The photobiont partner is a member of the cyanobacterial genus Nostoc. In the squamulose to microfoliose species, the lobes are rounded to elongated, and the branches in microfruticose species are terete (more or less circular in cross-section) and delicate. The ascomata are in the form of apothecia, and they are usually biatorine (where the outer layers of the apothecium are light-coloured and contain no algae). The hamathecium (a collective term for all kinds of hyphae or other tissues between asci) consists of unbranched to branched paraphyses, and is amyloid.[7]

The asci are semifissitunicate (i.e., discharge of spores from the ascus involves the separation of wall layers), with a thin apical tholus (the thickened inner part of an ascus tip) with an amyloid ring-structure, and cylindrical.[7] The structure of the asci is particularly important in distinguishing between related families in the Peltigerales. For example, Peltigeraceae has a distinctive apical tube, while Nephromataceae lacks any amyloid apical structure, and Lobariaceae has an indistinctive amyloid layer that is not comparable to the apical cap found in the asci of the Massalongiaceae.[2]

There are eight ascospores in each ascus. The spores have septa that divide the spore transversely, and have a shape ranging from spindle-shaped (fusiform) to ellipsoid. The conidiomata are in the form of pycnidia; the conidia are hyaline, lack septa, and are rod-shaped to spindle-shaped. No secondary compounds are known to occur in the family.[7]

Habitat and distribution edit

Massalongiaceae lichens grow on rocks, and are often associated with bryophytes, growing among or on top of them. Collectively, the family has a cosmopolitan distribution,[7] but with more representation in northern temperate zones.[8]

Genera and species edit

 
Leptochidium albociliatum

Several additional species of Massalongia have been described, but some cannot be identified precisely due to lack of sufficient type material, as they are only known from the type collection, and some have been transferred to other genera.[12]

References edit

  1. ^ Wijayawardene, Nalin; Hyde, Kevin; Al-Ani, Laith Khalil Tawfeeq; Somayeh, Dolatabadi; Stadler, Marc; Haelewaters, Danny; et al. (2020). "Outline of Fungi and fungus-like taxa". Mycosphere. 11: 1060–1456. doi:10.5943/mycosphere/11/1/8. hdl:10481/61998.
  2. ^ a b Wedin, Mats; Jørgensen, Per Magnus; Wiklund, Elisabeth (2006). "Massalongiaceae fam. nov., an overlooked monophyletic group among the cyanobacterial lichens (Peltigerales, Lecanoromycetes, Ascomycota)". The Lichenologist. 39 (1): 61–67. doi:10.1017/s002428290700655x. S2CID 86749909.
  3. ^ Hertel, Hannes (2012). Gattungseponyme bei Flechten und Lichenicolen Pilzen. Bibliotheca Lichenologica (in German). Vol. 107. Stuttgart: J. Cramer. p. 78. ISBN 978-3-443-58086-5.
  4. ^ Kraichak, Ekaphan; Huang, Jen-Pan; Nelsen, Matthew; Leavitt, Steven D.; Lumbsch, H. Thorsten (2018). "A revised classification of orders and families in the two major subclasses of Lecanoromycetes (Ascomycota) based on a temporal approach". Botanical Journal of the Linnean Society: 233–249. doi:10.1093/botlinnean/boy060.
  5. ^ Wiklund, Elisabeth; Wedin, Mats (2003). "The phylogenetic relationships of the cyanobacterial lichens in the Lecanorales suborder Peltigerineae". Cladistics. 19 (5): 419–431. doi:10.1111/j.1096-0031.2003.tb00312.x. PMID 34905834.
  6. ^ Wedin, M.; Wiklund, E. (2004). "The phylogenetic relationships of Lecanorales suborder Peltigerineae revisited". Symbolae Botanicae Upsalienses. 34 (1): 469–475.
  7. ^ a b c d Jaklitsch, Walter; Baral, Hans-Otto; Lücking, Robert; Lumbsch, H. Thorsten (2016). Frey, Wolfgang (ed.). Syllabus of Plant Families: Adolf Engler's Syllabus der Pflanzenfamilien. Vol. 1/2 (13 ed.). Berlin Stuttgart: Gebr. Borntraeger Verlagsbuchhandlung, Borntraeger Science Publishers. pp. 133–134. ISBN 978-3-443-01089-8. OCLC 429208213.
  8. ^ Cannon, P.F.; Kirk, P.M. (2007). Fungal Families of the World. Wallingford, UK: CAB International. p. 199. ISBN 978-0-85199-827-5.
  9. ^ Choisy, M. (1952). "Catalogue des lichens de la region lyonnaise. Fasc. 9". Bulletin Mensuel de la Société Linnéenne de Lyon (in French). 21: 165–180. doi:10.3406/linly.1952.7511.
  10. ^ Körber, G.W. (1855). Systema lichenum Germaniae (in Latin). Breslau: Trewendt & Granier. p. 109.
  11. ^ Gray, S.F. (1821). A natural arrangement of British plants. Vol. 1. London: Baldwin, Cradock, and Joy. p. 401.
  12. ^ Jørgensen, Per M.; Andersen, Heidi L.; Elvebakk, Arve (2019). "The genus Massalongia (lichenised ascomycetae) in the Southern Hemisphere". MycoKeys. 60: 125–140. doi:10.3897/mycokeys.60.37725. PMC 6906167. PMID 31844414.