Sawadaea bicornis (Wallr. : Fr.) Homma

Data Set Maintenance: Data set compiled and standard item. Data set author(s): Kainz C. (00-07-27). Data set reviewer(s): Schubert K. (06-04-05); revised.

Nomenclature: Current taxonomic status: accepted. Taxonomic rank: species. Synonyms: Erysiphe bicornis (Wallr.) Fr.; Erysiphe aceris DC.; Erysiphaceae Tul. & C. Tul.; Erysiphales.

Type Information: Basionym: Alphitomorpha bicornis Wallr. Type: Alphitomorpha bicornis Wallr.

Taxonomic Literature: Taxonomic notes: +conidiophores foot-cells cylilndric, followed by shorter cells, mostly 2;+appressoria nipple-shaped to moderately lobed or inconspicuous;+ascomata outer wall cells irregularly polygonal, obscure, ca. 8-15 µm diam.;. Braun U., Beih. Nova Hedwigia 89: 1-700 [441-442] (1987); Braun U., The powdery mildews (Erysiphales) of Europe. - 1-337. Jena, Stuttgart, New York (1995).

Biogeography: Continent: Asia-Temperate, Australasia, and Europe (all). Region(s): Siberia, Far Eastern Asia, China, and New Zealand (introduced). Country or state(s): Denmark, United Kingdom, Norway, Sweden, Austria, Benelux (Belgium & Luxembourg), former Czechoslovakia (incl. Czech Republic & Slovacia), Germany, Hungary, Netherlands, Poland, Switzerland (incl. Liechtenstein), France (excl. Corsica), Portugal, Spain (incl. Andorra & Monaco), Bulgaria, Greece, Italy (incl. San Marino & The Vatican City, excl. Sicily, Sardinia), Romania, European Turkey, Former Yugoslavia [incl. Bosnia and Herzegovina, Croatia, Macedonia, Moldova, Serbia and Montenegro, Slovenia], Belarus, Baltic States (Estonia, Lithuania, Latvia), and Ukraine; Japan and Iran (and Central Asia).

Ecology: Biotroph; phytopathogenic; growing on leaves, amphigenous. Host or Phorophyte Taxonomy: Acer campestre L.; Acer, Aceraceae.

Reproduction Strategy: With sexual (and possible asexual) stages. Ascocarps: Cleistothecioid, orbicular, forming independently from the host thallus or mycelium, scattered or in loose groups, (.11)-.12-.2-(.25) mm in diam.. Margin: External filaments present; uncinate, circinate, or sub-helicoid, .5-1 µm long, 5-8-(10) µm in diameter, hyaline, numerous, 35-100 per mm², growing on the upper half of the ascocarp, stiff and straight, smooth or rough (at the base), thick (throughout), not ramified or ramified, dichotomously branched (1-2(-3) times, deeply cleft, first branching point near the middle of the stalk, sometimes branched in the lower half, simple and branched appendages mixed, but branched ones dominant), aseptate.

Asci: (4)-6-18 asci per ascocarp, not stipitate or indistinctly stipitate, 50-95 µm long, 30-60 µm wide; dehiscence unitunicate.

Ascospores: c. 8 per ascus, spores (6)-8 per ascus, subglobose (rarely; or somewhat irregular), ellipsoid, ovoid, or sub-cylindrical, 15-28 µm long, 9-15 µm wide; septa absent.

Conidiomata: Present; hyphomycetous.

Conidiophores: Euoidium-type; branched; basal cells (20)-30-50 µm long, (6)-7.5-10 µm wide. Conidium Formation: Conidiogenous cells in chains. Conidia: Ellipsoid, ovoid, doliiform, or more or less cylindrical (with angular outline); microconidial (micro-conidiophores and micro-conidia frequently present, small, ca. 12-18 x 5-12 µm, micro-conidiophores foot-cells 20-40(-100) x 5-7.5 µm; germ tubes at an end or at a side of the spore, short to moderately long, ca. 5-40 x 2.5 µm, termínating in an unlobed appressorium or occasionally in a moderately lobed appressorium) or macroconidial (macro-conidia: shape variable, l/w ratio ca. 1.3-2.1), not branched, (20)-25-35-(36) µm long, (12)-13-18-(21) µm wide; aseptate; with distintly visible fibrosin body fibrosin bodies.

(report generated 04.Okt.2007)