Parafuscosporella pyriformis H. Yang, W. Dong & 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 : 27

Parafuscosporella pyriformis H. Yang, W. Dong & H. Zhang , sp. nov. ( FIGURE 5 , 6 )

Index Fungorum number: IF557319; Facesoffungi number: FoF06887

Etymology:—referring to the pyriform conidia.

Saprobic on decaying wood in freshwater habitats. Sexual morph: undetermined. Asexual morph: Colonies on natural substrata sporodochial, scattered, granular, black, with jelly-like covering. Mycelium partly superficial and partly immersed, composed of septate, branched, smooth-walled, hyaline, 0.5–1 µm wide hyphae. Conidiophores micronematous, mononematous, cylindrical or moniliform with globose to subglobose or ellipsoidal cells, compact, erect or flexuous, simple or branched, hyaline, smooth-walled, 10–40 × 2–13 μm. Conidiogenous cells holoblastic, monoblastic, integrated, sometimes discrete, terminal, smooth-walled, hyaline, cylindrical to clavate, 2–3 × 0.5–1 μm, or globose to subglobose, 8–13 μm in diam.. Conidia acrogenous, obovoid to pyriform, 2–3-celled with thick transverse septum near the base, sometimes with a small (6–7 × 6–10 μm) protuberance at base, dark brown to black when mature, olivaceous at immaturity, basal cells brown, smooth-walled, 23–30 × 16–26 μm (= 26 × 19 μm, n = 25).

Cultural characteristics:—Conidia germinating on PDA within 48 hours. Germ tubes produced from the basal cell. Colonies on PDA slow-growing, reaching 0.5 μm diameter in a month at 20–25°C, floccose, rounded, sallow at first, becoming grey to dark grey when aged with sparse mycelia on the surface, reverse sallow, yellowish grey with age, with undulate margin. Conidiophores micronematous, branched, sometimes reduced to a single conidiogenous cell, rising from submerged and aerial hyphae, 1–2.5 μm wide, pale brown to brown. Conidiogenous cells holoblastic, monoblastic, integrated, cylindrical, smooth-walled, brown, 1.5–3 μm wide. Conidia globose to subglobose, sometimes moniliform, aseptate, smooth, light brown to brown, 8–12 × 7–12 μm (= 10 × 9 μm, n = 30).

Material examined:— THAILAND. Nakhon Si Thammarat Province: on dead submerged decaying wood of an unidentified plant in a river, 10 May 2018, Wei Dong, Hat 649 ( MFLU 18–1520 , holotype), ex-type living culture MFLUCC18–1400 ; CHINA. Yunnan Province: Puzhehei Wetland , 24°8’32’’N, 104°6’58’’E, on submerged decaying wood of an unidentified plant, 12 May 2018, Hao Yang, P 21 ( MFLU 19–0525 , Paratype), living culture KUMCC 19–0008 .

Notes:— Parafuscosporella pyriformis fits well with the generic concept of Parafuscosporella and phylogenetically clustered within the genus.It differs from P.aquatic , P.moniliformis and P.mucosa in having two shapes of conidiogenous cells, viz. cylindrical and subglobose. Parafuscosporella garethii also has cylindrical and subglobose conidiogenous cells, but conidia of P. garethii are obpyramidal and coronate at the apex which is different from obovoid to pyriform conidia in P. pyriformis . Moreover, P. pyriformis reproduces globose to subglobose, sometimes moniliform, aseptate, smooth, light brown to brown conidia in culture.

Figures

FIGURE 5. Parafuscosporella pyriformis (MFLU 18–1520, holotype) a, b Sporodochia on submerged wood. c Squash mount of colony. d Conidiophores with conidia.e Subglobose conidiogenous cells with conidia.f Cylindrical conidiogenous cells with conidia. g–j Conidia. m Germinated conidium on PDA. k, l Culture on PDA, k from above, l from reverse. Scale bars: c–f, m = 20 μm, g–j = 10 μm.

FIGURE 6. Sporulation of Parafuscosporella pyriformis on PDA. a–i Conidia and conidiogenous cells from culture. Scale bars: a–i = 10 μm.