Parafuscosporella aquatica H. Yang & H. Zhang, 2020

Yang, Hao, Dong, Wei, Yu, Xian-Dong, Bhat, D. Jayarama, Boonmee, Saranyaphat & Zhang, Huang, 2020, Four freshwater dematiaceous hyphomycetes in Sordariomycetes with two new species of Parafuscosporella, Phytotaxa 441 (1), pp. 19-34 : 24-27

Parafuscosporella aquatica H. Yang & H. Zhang , sp. nov. ( FIGURE 3 , 4 )

Index Fungorum number: IF557318, Facesoffungi number: FoF06886

Etymology:—referring to the aquatic habitat.

Saprobic on decaying wood in freshwater habitats. Sexual morph: undetermined. Asexual morph: Colonies on natural substrata sporodochial, effuse, black, scattered, granular. Mycelium partly immersed, partly superficial, composed of septate, branched, smooth-walled, hyaline hyphae. Conidiophores micronematous, mononematous, compact, mostly moniliform, with globose to subglobose cells, hyaline, smooth-walled. Conidiogenous cells holoblastic, monoblastic, integrated, terminal, smooth-walled, hyaline, globose to subglobose, 7–14 × 8–11 μm. Conidia acrogenous, ellipsoidal to obovoid, with a septum near the base, dark brown to black at the apical cell, paler at the basal cell, smooth-walled, 20–29 × 13–19 μm (= 26 × 16 μm, n = 40).

Cultural characteristics: —Conidia germinating on PDA within 48 h. Germ tubes produced from the basal cell. Colonies on PDA slow-growing, reaching 4.4 cm diameter in 60 days at 20–25°C, brown, with dense, tight mycelia on the surface, sparse at the margin, reverse dark brown, with smooth margin. Conidiophores reduced to a single conidiogenous cell. Conidiogenous cells holoblastic, monoblastic, integrated, smooth-walled, hyaline to pale brown. Conidia obovoid to pyriform, mostly with a septum near the base, smooth, light brown to brown when young, brown to dark brown when aged, 16–24 × 9–16 μm (= 19 × 12 μm, n = 30).

Material examined: — THAILAND. Mukdahan Province: Nong Bo Na Kae, 16°84’96’’N, 104°33’12’’E, on dead submerged decaying wood of an unidentified plant in a small river, 13 December 2018, Hao Yang, t43 ( MFLU 19–0550, holotype), ex-type living culture KUMCC 19–0211.

Notes: —In the phylogenetic analysis, Parafuscosporella aquatica clustered within Parafuscosporella as a sister taxon to P. moniliformis ( FIGURE 1 ). There are 34 (including 4 gaps) and 128 base pairs (including 35 gaps) differences in LSU and ITS sequences between the two species, respectively. They are recognized as distinct species based on guidelines in Jeewon & Hyde (2016). Morphologically, P. aquatica differs from P. moniliformis by shorter conidiophores (7–14 × 8–11 μm vs. 5.5–36 × 5–21 μm) and smaller conidia (= 19 × 12 μm vs. = 32 × 17 μm) ( Yang et al. 2016). In culture, P. aquatica has obovoid to pyriform, uniseptate conidia, while P. moniliformis produces globose to subglobose, aseptate conidia.

Figures

FIGURE 1. Maximum likelihood majority rule consensus tree for Savoryellomycetidae based on a dataset of combined LSU, SSU, ITS and RPB2 sequence data. Bootstrap support values for maximum likelihood equal to or greater than 80% and Bayesian posterior probabilities equal to or greater than 0.95 are given above the nodes, respectively. The strain numbers are noted after the species names. Ex-type strains are in bold, newly generated sequences are indicated in blue, and new species are indicated in red. The tree is rooted with Leotia lubrica (AFTOL-ID 1) and Microglossum rufum (AFTOL-ID 1292). Orders are indicated as coloured blocks.

FIGURE 3. Parafuscosporella aquatica (MFLU 19–0550, holotype) a, b Sporodochia on submerged wood. c, d Squash of colonies. e, f Conidiogenous cells with conidia. g–l Conidia. m Germinated conidium on PDA. n, o Culture on PDA, n from above, o from reverse. Scale bars: c, d, m = 20 μm, e, f= 10 μm, g–l = 10 μm.

FIGURE 4. Sporulation of Parafuscosporella aquatica on PDA. a Hyphae and conidia from culture. b–f Conidiogenous cells with conidia. Scale bars: a = 100 μm, b–d = 20 μm, e–f = 10 μm.