Rhytisma acerinum (Pers.) Fr.
(Sycamore Tar-spot, Tar-spot Fungus)

Taxonomic hierarchy:
SpeciesRhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus)
GenusRhytisma (tar-spot fungi)
FamilyRHYTISMATACEAE (a family of ascomycetes)
OrderRHYTISMATALES (an order of ascomycetes)
SubclassLEOTIOMYCETIDAE (powdery mildews)
ClassLEOTIOMYCETES (a class of fungi)
SubphylumPEZIZOMYCOTINA (a subphylum of ascomycetes)
PhylumASCOMYCOTA (spore shooters, ascomycete)
KingdomFUNGI (true fungi)
DomainEukaryota (eukaryotes)
LifeBIOTA (living things)
Records of Rhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus) :
1: Rhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus)
25 Oct 2009 OSGR: SU46 51° 20’ N, 1° 20’ W Vice County: North Hants (VC 12) England
black sclerotia on Sycamore leaves
Image 1: Apothecia - closed - highly enlargedImage 2: Apothecia - closed - highly enlarged (2)Image 3: Apothecia - dry - almost closed - enlargedImage 4: Apothecia - dry - almost closed - enlarged (2)Image 5: Apothecia - half dry - half open - enlargedImage 6: Apothecia - half moist - just opening - highly enlargedImage 7: Apothecia - moist - open - enlargedImage 8: Apothecia - moist - open - highly enlargedImage 9: Apothecia - moist - open - highly enlarged (2)Image 10: Apothecia - wet - open - highly enlargedImage 11: Apothecia - wet - open - highly enlarged (2)Image 12: Apothecia - wet - open - highly enlarged (3)Image 13: Apothecia - wet - wide open - highly enlargedImage 14: Apothecia - wet - wide open - highly enlarged (2)Image 15: Apothecia - wet - wide open - highly enlarged (3)Image 16: Apothecia - wet - wide open - highly enlarged (4)Image 17: Apothecia - wet - wide open - highly enlarged (5)Image 18: Apothecia - wet - wide open - highly enlarged (6)Image 19: Asci and paraphyses in squash prep. - magnifiedImage 20: Asci and paraphyses in squash prep. - magnified (2)Image 21: Asci and paraphyses in squash prep. - magnified (3)Image 22: Asci and paraphyses in squash prep. - magnified (4)Image 23: Asci and paraphyses in squash prep. - magnified (5)Image 24: Asci and paraphyses in squash prep. - magnified (6)Image 25: Asci and paraphyses in squash prep. - magnified (7)Image 26: Asci and paraphyses in squash prep. - magnified (8)Image 27: Asci and paraphyses in squash prep. - magnified (9)Image 28: Asci and paraphyses in squash prep. - magnified (10)Image 29: Asci and paraphyses in squash prep. - magnified (11)Image 30: Asci and paraphyses in squash prep. - magnified (12)Image 31: Asci and paraphyses in squash prep. - magnified (13)Image 32: Asci and paraphyses in squash prep. - microscope low magnificationImage 33: Exciple in squash prep. - magnifiedImage 34: Exciple in squash prep. - magnified (2)Image 35: Paraphyses and asci in squash prep. - magnifiedImage 36: Paraphyses and asci in squash prep. - magnified (2)Image 37: Paraphyses and asci in squash prep. - magnified (3)Image 38: Paraphyses and asci in squash prep. - magnified (4)Image 39: Paraphyses and asci in squash prep. - magnified (5)
2: Rhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus)
8 Jul 2008 OSGR: SK28 53° 20’ N, 1° 30’ W Vice County: South-west Yorks (VC 63) England
early infection on Sycamore leaves
Image 1: Leaf with early infection - in situImage 2: Leaf with early infection - in situ (2)Image 3: Leaf with early infection - in situ (3)Image 4: Leaf with early infection - white backgroundImage 5: Leaf with early infection - white background (2)Image 6: Leaf with early infection - white background (3)Image 7: Leaf with early infection - white background (4)Image 8: Leaves with early infection - in situImage 9: Leaf spot - top surface - close-up - magnifiedImage 10: Leaf spot - top surface - close-up - magnified (2)Image 11: Leaf spot - top surface - close-up - magnified (3)Image 12: Leaf spot - top surface - close-up - magnified (4)Image 13: Leaf spot - top surface - close-up - magnified (5)Image 14: Conidia - highly magnifiedImage 15: Conidia - highly magnified (2)Image 16: Conidioma wall - magnifiedImage 17: Conidioma wall - magnified (2)Image 18: Conidiophore pallisade - magnifiedImage 19: Conidiophore pallisade - magnified (2)Image 20: Conidiophore pallisade - highly magnified
3: Rhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus)
30 Aug 2007 OSGR: SK15 53° 10’ N, 1° 50’ W Vice County: Derby (VC 57) England
Melasmia coelomycetous anamorph on black leaf-spots on Sycamore leaf
Image 1: Infected leaf - top surface - pale backgroundImage 2: Infected leaf - under surface - pale backgroundImage 3: Leaf spot margin - top surface - magnifiedImage 4: Leaf spot margin - top surface - magnified (2)Image 5: Leaf spot margin - top surface - magnified (3)Image 6: Leaf spots - top surface - close-up - enlargedImage 7: Leaf spots - top surface - close-up - enlarged (2)Image 8: Leaf spots - top surface - close-up - enlarged (3)Image 9: Leaf spots - top surface - close-up - enlarged (4)Image 10: Leaf spots - top surface - close-up - enlarged (5)Image 11: Leaf spots - top surface - close-up - enlarged (6)Image 12: Leaf spots - under surface - close-up - enlargedImage 13: Leaf spots - under surface - close-up - enlarged (2)Image 14: Leaf spots - under surface - close-up - enlarged (3)Image 15: Leaf spots - under surface - close-up - enlarged (4)Image 16: Leaf spots - under surface - close-up - enlarged (5)Image 17: Leaf spot - top surface - clypeus scraped away - magnifiedImage 18: Leaf spot - top surface - clypeus scraped away - magnified (2)Image 19: Leaf spot - top surface - magnifiedImage 20: Leaf spot - top surface - magnified (2)Image 21: Leaf spot - top surface - magnified (3)Image 22: Leaf spot - under surface - magnifiedImage 23: Leaf spot - under surface - magnified (2)Image 24: Clypeus - magnifiedImage 25: Clypeus - magnified (2)Image 26: Clypeus - microscope low magnificationImage 27: Conidia - magnifiedImage 28: Conidia - highly magnifiedImage 29: Conidia - highly magnified (2)Image 30: Conidia - highly magnified (3)
4: Rhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus)
13 Oct 1997 OSGR: SU56 51° 30’ N, 1° 20’ W Vice County: Berks (VC 22) England
on sycamore leaves
Image 1: Stroma on Sycamore leaf
5: Rhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus)
7 May 1976 OSGR: SD67 54° 10’ N, 2° 30’ W Vice County: Mid-west Yorks (VC 64) England
Image 1: Apothecia - magnified
6: Rhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus)
27 Sep 1974 OSGR: SK27 53° 10’ N, 1° 40’ W Vice County: Derby (VC 57) England
on Sycamore leaf
Image 1: Stroma - in Autumn - enlarged

Identification Works

AuthorYearTitleSource
Forest Research 2009 Path News Issue 19: October 2009
Forest Research 2004 Path News Issue 9: October 2004
Minter, D. 1990 First Steps: Little Black Spots Mycologist Vol 4(1): 38-39.
Weber, R.W.S. & Webster, J. 2002 Teaching techniques for mycology: 18. Rhytisma acerinum, cause of tar-spot disease of sycamore leaves Mycologist Vol 16 (3): 120-123.

Rhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus) may also be included in identification literature listed under the following higher taxa:

NBNNBN (data.nbn.org.uk) has a distribution map for Rhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus)
BioInfoBioInfo (www.bioinfo.org.uk) has 7 host/parasite/foodplant and/or other relationships for Rhytisma acerinum (Sycamore Tar-spot, Tar-spot Fungus)
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