Pleosporales » Dictyosporiaceae » Dictyocheirospora

Dictyocheirospora metroxylonis

Dictyocheirospora metroxylonis Konta & K.D. Hyde, Fungal Diversity 95: 11 (2019).

Index Fungorum number: IF555290         Facesoffungi number: FoF04833

 

Saprobic on dead Metroxylon sagu. Sexual morph: Undetermined. Asexual morph: Hyphomycetous. Sporodochia on natural substrate in small groups, punctiform, 100–200 μm diam. (x̄ = 130 μm, n = 10), velvety, greyish to dark brown. Mycelium immersed, composed of brown, smooth, thin-walled, septate, branched hyphae. Conidiophores micronematous, pale brown, smooth, thin-walled. Conidiogenous cells 3–8 × 3–5 μm (x̄ = 5.2 × 4.6 μm, n = 10), holoblastic, integrated, terminal, determinate, pale brown, smooth-walled. Conidia 45–69 × 15–29 μm (x̄ = 61 × 20 μm, n = 20), solitary, monoblastic, acrogenous, cheiroid, pale brown, consisting of 4–6 rows of cells, rows digitate, cylindrical, inwardly curved at the tip, arising from a basal cell, each arm composed of 9–14 cells, distoseptate, constricted at the septa, large guttule in each central cell. Conidial arm 29–58 × 5–7 μm (x̄ = 47 × 6 μm, n = 10).

 

Culture characteristics: Conidia germinated on MEA within 24 h and germ tubes produced from the basal cells of the conidium. Colonies on MEA reaching 7–7.5 cm diam. after 2 weeks, at 25–28 °C, initially white, becoming grey-light brown, not sporulating on media.

 

Habitat: on dead plant materials of Metroxylon sagu

 

Known distribution: Thailand

 

Material examined: THAILAND, Krabi Province, on dead Metroxylon sagu Rottb. (Arecaceae), 8 December 2014, S. Konta, KBR04d (MFLU 15-0028, holotype), ex-type living culture, MFLUCC 15-0282.

 

GenBank numbers: ITS = MH742321, LSU = MH742313, SSU = MH742317, (MFLUCC 15-0282a); ITS = MH742322, LSU = MH742314, SSU = MH742318, TEF1-α = MH764301 (MFLUCC 15-0282b); ITS = MH742323, LSU = MH742315, SSU = MH742319, TEF1-α = MH764302 (MFLUCC 15-0282c); ITS = MH742324, LSU = MH742316, SSU = MH742320, TEF1-α = MH764303 (MFLUCC 15-0282d).

 

Notes: Dictyocheirospora metroxylonis differs from other Dictyocheirospora species by its conidial size, and number of rows and cell numbers in each row. Phylogenetic analyses of a combined ITS, LSU, SSU and TEF1-α sequence dataset show that D. metroxylonis forms a distinct lineage, clustered with other Dictyocheirospora species with moderate support in ML analysis (84% ML) and high support in BI analysis (0.99 BYPP). Since Dictyocheirospora has been introduced in Dictyosporiaceae (Dothideomycetes), many species were subsequently introduced to this genus with morphological and phylogenetic evidence. Interestingly, D. metroxylonis strain MFLUCC 150282d formed a clear zone against contaminated fungi on MEA during our experiment.