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Description type:Original description 
Description:After 3 days growth on 5% ME agar at 25 uC, cells are
spherical, 2.0–4.0 mm, to elongate, 2.0–3.062.5–8.0 mm,
and often teardrop-shaped. Cells form by multilateral budding
and may be single or in pairs. Not infrequently, cells
4–566–8 mm have a tapered seta-like extension that has a
basal diameter of 1.0–1.3 mm and a length of 18–125 mm (Fig. 2c). Seta-bearing cells often produce buds. Colony
growth on 5% ME agar is white with an almost powdery
appearance and a prominent mycelial fringe. After 7 days at
25 uC, growth under the cover glass of a Dalmau plate
culture with YMo agar shows pseudohyphae and abundant
true hyphae with side branches having highly denticulate
tips bearing blastoconidia. Hyphal cells also form denticles
with blastoconidia (Fig. 2d). Aerobic colonies are white,
mycelial and somewhat powdery with an entire to lobate
margin. Reactions for fermentation, assimilation and other
diagnostic tests are given in Table 3. Moderately thick, climbing pellicles are formed on stationary liquid media.
Cultures grown on YM, 5% ME and RG agar media at 15
and 25 uC produced no ascospores after 6 weeks. The type
strain differs from B. mokoenaii NRRL Y-27120T and B.
malaysiensis sp. nov. NRRL Y-6417T by just two nucleotide
substitutions in the D1/D2 domain of the LSU rDNA. This
small difference raised the possibility that the taxa may be
conspecific. However, greater divergence was found in the
nucleotide sequences of ITS1–5.8S–ITS2 rDNA, mitochondrial
SSU rDNA and the COXII gene, providing additional
evidence that the three taxa are closely related but separate
species (Table 2). In further tests, cultures of the three
species were mixed on YM, 5% ME and RG media, incubated
at 25 uC and observed over a 6-week period. Neither
conjugation between cells nor ascospores was detected.
Cultures of B. mokoenaii, especially on 5% ME agar,
occasionally formed spherical endospores in hyphal cells.
NRRL YB-1343T (=CBS 10339T) is the designated type
strain and is preserved as a lyophilized preparation in the
ARS Culture Collection (NRRL), Peoria, IL, USA. The strain
was isolated by L. J. Wickerham in 1949, from debris
surrounding the base of a standing, dead deciduous tree near
Marion, IL, USA.
 
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