Micromelanconis C.M. Tian & N. Jiang, 2021

Jiang, Ning, Yang, Qin, Fan, Xin-Lei & Tian, Cheng-Ming, 2021, Micromelanconis kaihuiae gen. et sp. nov., a new diaporthalean fungus from Chinese chestnut branches in southern China, MycoKeys 79, pp. 1-16 : 1

Micromelanconis C.M. Tian & N. Jiang gen. nov.

Etymology.

Name derived from micro- and the genus name Melanconis .

Type species.

Micromelanconis kaihuiae C.M. Tian & N. Jiang.

Description.

Sexual morph: not observed. Asexual morph: Conidiomata acervular, conspicuous, immersed in host bark to erumpent, covered by brown to blackish exuding conidial masses at maturity. Central column beneath the disc more or less conical. Conidiophores unbranched, aseptate, cylindrical, pale brown, smooth-walled. Conidiogenous cells annellidic, occasionally with distinct annellations and collarettes. Conidia hyaline when immature, becoming pale brown, ellipsoid, multiguttulate, aseptate, with hyaline sheath. Conidiomata formed on PDA after three weeks, randomly distributed, and black. Conidiophores unbranched, septate, cylindrical, pale brown, smooth-walled. Conidiogenous cells annellidic. Conidia pale brown, long dumbbell-shaped, narrow at the middle and wide at both ends, multiguttulate, aseptate, with hyaline sheath.

Notes.

Micromelanconis is the third genus after Neopseudomelanconis and Pseudomelanconis in the family Pseudomelanconidaceae (Fig. 1 ). Micromelanconis is united in this family based on the Melanconis -like conidiomata, and pale brown conidia with conspicuous hyaline sheath. Micromelanconis produces two types of conidia from natural branches and manual media respectively, which differs from Neopseudomelanconis and Pseudomelanconis ( Fan et al. 2018a; Jiang et al. 2018a). Additionally, Neopseudomelanconis is characterized by its septate conidia ( Jiang et al. 2018a).

Figures

Figure 1. Phylogram of Diaporthales from a maximum likelihood analysis based on combined ITS, LSU, tef 1 a and rpb 2. Values above the branches indicate maximum likelihood bootstrap (left, ML BP ≥ 50 %) and Bayesian probabilities (right, BI PP ≥ 0.90). The tree is rooted with Nakataea oryzae (CBS 243.76) and Pyricularia grisea (Ina 168). New species proposed in the current study is in blue and the ex-type strains are marked with *.