The genus Siphula includes lichens with a shrubby, upright thallus (the lichen body) that is sparsely branched and has a whitish appearance. The outer surface, or cortex, is pseudoparenchymatous, meaning it consists of densely packed cells resembling plant parenchyma (common plant tissue). Siphula species partner with chlorococcoid algae, a type of green algae that supplies the lichen with energy through photosynthesis.[4]
Inside the thallus, the medulla (inner tissue layer) is compact and has fungal filaments (hyphae) that are generally aligned in a longitudinal direction. No reproductive structures, such as apothecia (spore-producing bodies) or conidiomata (asexual spore-producing bodies), have been observed to occur in this genus.[4]
Siphula species are found growing on peaty soils and on acid-leached bark in temperate rainforests as well as in wet alpine environments. This genus has a cosmopolitan distribution, occurring across various regions worldwide.[4]
^ abKantvilas, G. (2023). "Three new species of siphuloid lichens, with a first key to the genus Parasiphula". The Lichenologist. 55 (1): 17–25. doi:10.1017/S0024282922000421.
^ abcMarcano, V. (2021). "The genus Siphula Fr. (Icmadophilaceae, Lichenized Fungi) in Venezuela". Phytotaxa. 489 (1): 10–26. doi:10.11646/phytotaxa.489.1.2.
^Nylander, W. (1860). Synopsis Methodica Lichenum Omnium hucusque Cognitorum, Praemissa Introductione Lingua Gallica [Methodical Synopsis of All Known Lichens, With an Introduction in French] (in Latin). Vol. 1. pp. 141–430.
^ abNylander, W. (1888). Lichenes Novae Zelandiae [Lichens of New Zealand] (in Latin). Paris: Paul Schmidt. pp. 1–156.
^Kantvilas, G. (1998). "Studies on the lichen genus Siphula in Tasmania II. The S. decumbens group". Herzogia. 13: 119–138. doi:10.1127/herzogia/13/1998/119.
^Marcano, V.; Castillo, L. (2021). "Siphula paramensis V. Marcano & L. Castillo (Icmadophilaceae, lichenized fungi), a new species from the high paramo in Venezuela". Phytotaxa. 512 (3): 169–178. doi:10.11646/phytotaxa.512.3.4.