Degelia crustacea
Family
Pannariaceae
Flora category
Lichen – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Lichens - Crustose
Current conservation status
2018 | Data Deficient | Qualifiers: SO
Brief description
Characterised by the corticolous habit; the crustose to subsquamulose thallus; the paraplectenchymatous upper cortex of anticlinal hyphae; the I+ blue reaction of the hymenium; ellipsoidal ascospores, 10–15 × 5–8 μm; and a negative chemistry.
Distribution
North Island: Northland (Waipoua, Kawakawa, Russell) to Auckland (Waitakere Ranges) and South Auckland (Hunua Ranges).
On bark of lowland coastal trees and shrubs. Known also from Australia (NSW) and Juan Fernandez.
Habitat
A pioneer of bare bark of stems or branches of trees and shrubs in humid, lowland, coastal forests of northern New Zealand, in regions with a subtropical climate. Like D. periptera it may prove to have a wider distribution area in the Tasman Sea region, and may be restricted to that region.
Detailed description
Thallus small-squamulose to crustose, squamules closely appressed, attached to a blue-black prothallus, forming orbicular patches to 3 cm diam. Squamules incised, sometimes lobulate, to 0.1 mm diam., not noticeably enlarged at margins. Upper surface blue-grey. Cortex 25 μm thick, paraplectenchymatous of anticlinal hyphae. Apothecia rather rare, brown to blackish, to 1 mm diam., with a distinct, coronate thalline exciple to 100 μm thick, and a paraplectenchymatous proper exciple to 125 μm thick. Hymenium colourless, I+ blue to 120 μm tall. Hypothecium yellowish to 100 μm thick. Asci cylindrical, 60–90 × 12–15 μm, with amyloid apical structures. Ascospores ellipsoidal, 10–15 × 5–8 μm. Pycnidia not seen.
Chemistry: TLC−, all reactions negative.
Similar taxa
It appears to be related to Degelia periptera, another northern species, which, however, has long, stellately radiating lobes that are apically fan-shaped, and a differing cortical anatomy (upper cortex not paraplectenchymatous). Sepertated from Degeliella by the hymenium I+ persistent blue.
Degelia crustacea is superficially similar to the subantarctic D. rosulata. It differs from that species in its more crustose habit and the blue, instead of reddish iodine reaction of the hymenium.
Substrate
Corticolous
Attribution
Fact sheet prepared by Marley Ford (5 September 2021). Brief description and Features sections copied from Galloway (2007). Habitat, and similar taxa copied form Jørgensen & Galloway (2000).
References and further reading
Galloway D.J. 2007: Flora of New Zealand: Lichens, including lichen-forming and lichenicolous fungi. 2nd edition. Lincoln, Manaaki Whenua Press. 2261 pp.
Jørgensen P.M., Kantvilas G., & Galloway D.J. 2000:. Three new species in the lichen genus Degelia. The Lichenologist, 32(3): 257-262.