Colletotrichum: complex species or species ... - CBS - KNAW

The Colletotrichum boninense species complex
Fig. 10. Colletotrichum dacrycarpi (from ex-holotype strain CBS 130241). A–B. Conidiomata. C–E. Conidiophores. F–G. Conidia. A, C, F. from Anthriscus stem. B, D–E, G. from
SNA. A–B. DM, C–G. DIC, Scale bars: A = 100 µm, B = 200 µm, C = 10 µm. Scale bar of C applies to C–Q.
On Anthriscus stem. Conidiomata globose, apparently opening
by rupture, wall cells medium brown, angular, 7–20 µm diam. Setae
not observed. Conidiophores hyaline, smooth-walled, septate,
branched, to 50 µm long, developing from a cushion of medium
brown, angular to rounded cells, 3.5–12 µm diam. Conidiogenous
cells hyaline to pale brown, smooth-walled, cylindrical, surrounded
by a gelatinous sheath, sometimes extending to form new
conidiogenous loci, 7.5–23 × 3–5 µm, the opening 1.5–2.5 µm
diam, collarette not observed, periclinal thickening observed.
Conidia hyaline, smooth-walled, aseptate, straight, cylindrical,
apex round, base round, granular to guttulate content, (13–)15.5–
19.5(–24) × 5–6(–6.5) µm, mean ± SD = 17.3 ± 2.0 × 5.5 ± 0.3
µm, L/W ratio = 3.2.
Culture characteristics: Colonies on SNA flat with entire margin,
hyaline to honey-coloured, with Anthriscus stem, filter paper
and medium partly covered white floccose aerial mycelium and
grey structures, orange conidial masses in the centre; reverse
hyaline, honey to pale salmon, with dark grey spots due to
conidiomata or ascomata shining through, 10.5–12.5 mm in 7
d (17.5–20 mm in 10 d). Colonies on OA flat with entire margin,
rosy buff to pale flesh with a buff margin, covert with sepia to
black conidiomata or ascomata and orange conidia masses in
the centre and very sparse white aerial mycelium; reverse buff
to rosy buff, 11–12.5 mm in 7 d (16–17.5 mm in 10 d). Conidia
in mass orange.
Material examined: New Zealand, Auckland, Wenderholm Regional Park, leaf
endophyte from Dacrycarpus dacrydioides (kahikatea), 16 Oct. 2009, G. Carroll,
(CBS H-20705 holotype, culture ex-type CBS 130241 = ICMP 19107).
Notes: There were no Colletotrichum species described from
Dacrycarpus species (Podocarpaceae) prior to this study.
Colletotrichum dacrycarpi does not look like a typical member
for the genus, with its slow growth and the production of conidia
within closed fruit-bodies with walls that rupture. These closed fruitbodies
have been observed in several other species within the C.
boninense complex, and the extension of conidiogenous cells to
form a new conidiogenous locus is typical of species within the C.
boninense complex. Colletotrichum dacrycarpi is one of the most
basal members of the overall clade, and forms a sister group to
the morphologically distinct C. constrictum. With all single gene
phylogenies, C. dacrycarpi is situated on a long branch. Blastn
searches with the ITS sequences found no close match.
Colletotrichum hippeastri Yan L. Yang, Zuo Y. Liu, K.D.
Hyde & L. Cai, Fungal Diversity 39: 133. 2009. Fig 11.
Teleomorph not observed. On SNA. Vegetative hyphae 1–6 µm
diam, hyaline to pale brown, usually smooth-walled, sometimes
warted, septate, branched. Chlamydospores not observed.
Conidiomata absent, conidiophores and setae formed directly
on hyphae. Setae medium brown, verruculose, 2–7-septate,
70–200 µm long, the base cylindrical or inflated, 4–7 µm diam,
the tip rounded. Conidiophores pale to medium brown, septate,
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