Podosphaera shepherdiae (U. Braun) U. Braun & S. Takam.

Data Set Maintenance: Data set compiled and standard item. Data set author(s): Kainz C. Data set reviewer(s): Schubert K. (06-05-16); revised.

Nomenclature: Current taxonomic status: accepted or basionymous. Taxonomic rank: species. Synonyms: Sphaerotheca shepherdiae U. Braun; Erysiphaceae Tul. & C. Tul.; Erysiphales.

Type Information: Basionym: Sphaerotheca shepherdiae U. Braun.

Taxonomic Literature: Taxonomic notes: +conidiophores foot-cells mostly slightly increasing from base to top, followed by (1-)2(-3) shorter cells, basal septum of the foot-cell sometimes away from the branching point of the mycelium;+appressoria indistinct;+ascoc. outer wall cells irregularly polygonal to rounded, obscure, ca. 10-20 µm diam., length sometimes up to 25 µm;+ascoc. ext. fil. length variable, mostly very short, shorter than the cleistoth. diam., occasionally up to 3 times the cleistoth. diam.;. Braun U., Beih. Nova Hedwigia 89: 1-700 [120] (1987).

Biogeography: Northern hemispheric. Continent: Northern America (USA, Alaska, Canada). Country or state(s): Alaska (USA), Alberta (Canada), Montana (USA), Wyoming (USA), Connecticut (USA), and Texas (USA). Checklist records: United States and Canada (continental).

Ecology: Biotroph; phytopathogenic; growing on leaves, amphigenous. Host or Phorophyte Taxonomy: Shepherdia argentea Nutt.; Shepherdia, Elaeagnaceae.

Reproduction Strategy: With sexual (and possible asexual) stages. Ascocarps: Cleistothecioid, orbicular, forming independently from the host thallus or mycelium, scattered or in loose groups, (.075)-.08-.1-(.11) mm in diam.. Margin: External filaments present; interlaced with each other, mycelioid, straight, up to 3 µm long, 4-8 µm in diameter, hyaline or pigmented (yellowish, rarely brownish), few or numerous, growing all across the lower half of the ascocarp, smooth, thin, not ramified, septate.

Asci: 1 asci per ascocarp, not stipitate, 60-85 µm long, 50-75 µm wide; dehiscence unitunicate.

Ascospores: c. 8 per ascus, spores 6-8 per ascus, subglobose (sometimes), ellipsoid, or ovoid, (16)-18-27.5 µm long, (10)-12-18 µm wide; septa absent.

Conidiomata: Present; hyphomycetous.

Conidiophores: Euoidium-type; not branched; basal cells at least 100 µm long, 10-14.5 µm wide. Conidium Formation: Conidiogenous cells in chains. Conidia: Ellipsoid, ovoid, or doliiform; macroconidial, not branched, 24-36 µm long, 16-21 µm wide; aseptate; with distintly visible fibrosin body fibrosin bodies.

(report generated 04.Okt.2007)