Image of Lachnellula occidentalis (G. G. Hahn & Ayers) Dharne 1965

Description:

Habitat: alpine valley, mixed forest edge, dominant Fagus sylvatica, Picea abies, Ostrya carprinifolia, Larix decidua, Fraxinus ornus, Fraxinus excelsior, Corylus avellana; modestly southeast inclined mountain slope, calcareous ground (overgrown old scree, rocks and boulders), limestone bedrock, relatively dry and warm place, partly sunny, exposed to direct rain, average precipitations ~ 3.000 mm/year, average temperature 7-9 deg C, elevation 600 m (1.950 feet), alpine phytogeographical region. - Substratum: dead, thin branches of Larix decidua still attached to the tree. - Comments: Several fruit bodies on several branches were found. The determination seems to me quite certain in spite of the fact that there exists many species in genus. L. occidentalis has relatively large spores, which, together with the substratum, much reduces number of options. The only eventual alternative seems to be Lachnellula willcommii. However it has broader spores (8-10 microns) and it is usually associated with Larix decidua cankers. All observed fruitbodies, except one (Figs. 9. and 10.), seem to grow on normal not deformed branches. - Spores smooth. Dimensions: (16.4) 17.8 - 21.8 (24.6) x (4.8) 6 - 7.9 (9.1) microns, Q = (2.2) 2.4 - 3.4 (3.7) ; N = 31; Me = 20 x 7 microns ; Qe = 2.9. Olympus CH20, NEA 100x/1.25, magnification 1.000 x, oil, in water. AmScope MA500 digital camera. Fruit body close up: Novex Trinocular. - Herbarium: Mycotheca and lichen herbarium (LJU-Li) of Slovenian Forestry Institute, Vena pot 2, Ljubljana, Index Herbariorum LJF - References and cited spore dimensions: (1) http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Lachnellula%20occidentalis 12-17 x 3.5-6 microns (2) http://nt.ars- grin.gov/taxadescriptions/factsheets/pdfPrintFile.cfm?thisApp=Lachnellulawillkommii 5-8.5 um wide (3) Dichotomous key to Lachnellula (worldwide), (Trichoscyphelloideae, Lachnaceae, Helotiales, Ascomycetes), with a synoptic table of characters (H.O. Baral, Feb. 2000, with updates until 2008, unpublished) available at 'In vivo veritas' Baral 14(16-22)24/7-8(9,5) (4) http://www.ascofrance.com/forum/21908/lachnellula-on-larix 16.3-20.8 X 5.6-7.1 (5) http://www.natur-in-nrw.de/HTML/Pilze/Ascomycota/PAS-175.html (13) 17-20 (24) x 5-8 m, (6) J. Breitenbach, F. Kraenzlin, Eds., Fungi of Switzerland, Vol.xx. Verlag Mykologia (1984), p 196. 12-17/3,5-6. (7) L. Hanse and H. Knudsen, Nordic Macromycetes cited in Ref.: (4) 18-20 X 7-9 m