Pachyascus is the sole genus in the family Pachyascaceae. It contains a single species, the lichen Pachyascus lapponicus. Both the genus and species were described as new to science in 1968 by lichenologists Josef Poelt and Hannes Hertel. P. lapponicus was originally collected from Lapland, a province in northern Sweden. The lichen has several unusual characteristics: it grows exclusively along with the rock moss Andreaea, it bears goniocyst-like parts (goniocysts are small aggregations of photobiont cells surrounded by fungal hyphae) and produces tiny apothecia that stand in the leaf axils of the moss, and it has thick asci.[1]

Pachyascus
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Fungi
Division: Ascomycota
Class: Lecanoromycetes
Order: Lecanorales
Family: Pachyascaceae
Poelt ex P.M.Kirk, P.F.Cannon & J.C.David (2001)
Genus: Pachyascus
Poelt & Hertel (1968)
Species:
P. lapponicus
Binomial name
Pachyascus lapponicus
Poelt & Hertel (1968)

Poelt and Hertel thought the species occupied a basal position in the order Lecanorales,[1] and Poelt tentatively placed it in its own family, Pachyascaceae in a 1974 publication.[2] This family was formally published in 2001.[3] In 2020, it was classed within the Lecanoromycetidae but within uncertain order placement.[4]

Another lichen, which bears a superficial resemblance in the ascomata, was once placed in Pachyascus as P. byssaceus (Vězda) Vězda (1970); it is now known as Vezdaea aestivalis.[5]

References

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  1. ^ a b Poelt, J.; Hertel, H. (1968). "Pachyascus lapponicus nov. gen. et spec., eine bemerkenswerte Flechtengattung unklaren Anschlusses". Berichte der Deutschen Botanischen Gesellschaft (in German). 81 (6): 210–216. doi:10.1111/j.1438-8677.1968.tb02123.x. S2CID 161441573.
  2. ^ Poelt, J. (1974). "Classification". In Ahmadjian, Vernon; Hale, Mason E. (eds.). The Lichens (1 ed.). New York and London: Academic Press. ISBN 978-0-12-044950-7.
  3. ^ Kirk, P.M.; Cannon, P.F.; David, J.C.; Stalpers, J.A. (2001). Ainsworth & Bisby's Dictionary of the Fungi (9 ed.). CABI Bioscience. p. IX. ISBN 978-0-85199-377-5.
  4. ^ 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.
  5. ^ "Record Details: Pachyascus byssaceus (Vězda) Vězda, Folia geobot. phytotax. 5(3-4): 318 (1970)". Index Fungorum. Retrieved 15 November 2021.