19-10-2025 18:58
Bernard CLESSE
Bonsoir à toutes et tous,Il y a un peu plus de de
19-10-2025 14:10
Camille MertensBonjour à tous.Asco stipité 1mm de texture appar
17-10-2025 18:45
Riet van Oosten
Hello, Found by Laurens van der Linde, Oct. 2025.
23-09-2025 13:31
Thomas Læssøehttps://svampe.databasen.org/observations/10534623
15-10-2025 16:39
Edvin Johannesen
These tiny (0.2-0.6 mm), white, pulvinate apotheci
03-10-2025 13:44
Riet van Oosten
Hello, Found by Laurens van der Linde on Populus
13-10-2025 19:05
Louis DENYBonjour forumSur tronc décortiqué de feuillu x,
11-10-2025 20:27
Marcel Heyligen
Found on a barked branch, 14 mm in diameter, of Ro
Growing on Acer macrophyllum (bigleaf maple). Seen at the Yuba Watershed Fungus Fair.No asci observed. Many parathyses with tiny oil drops were seen, they measured 30 – 45 × 2 – 3 micrometers. Many clavate basidia-like things seen, however they never had sterigmata or spores inside. Those measured (28) 36 – 47 x (5) 7 – 8 micrometers.
That is probably Rhytisma punctatum. The US host-index lists it on Acer macrophyllum in California, Oregon and Washington. The "clavate, basidia-like things" are probably immature asci. These would be mature in the spring at about the time the new leaves are emerging on the tree.
Dave
Here are some more macro images... http://mushroomobserver.org/156379?q=1higi?
Edit: I understand that punctuate dots like this on Acer macrophyllum = R. punctatum, but there is another species with a somewhat similar appearence on other maples.
http://www.glfc.forestry.ca/VLF/ForumPresentations/hsiangtarspot_08e.pdf