Saagaromyces mangrovei Abdel-Wahab, Bahkali & E.B.G. Jones.
Index Fungorum number: IF551073; Facesoffungi number: FoF 00488; Figs. 1 and 2
Etymology: In reference to the habitat where the fungus was first found.
Holotype: CBS H-22126

Saprobic on submerged wood in mangroves. Ascomata 370–520μm high, 200–380μm wide, sub-globose, ovate, obpyriform, ellipsoidal, horizontal, yellow-brown to brown, immersed, membranous, ostiolate and papillate. Peridium 45–65μm thick, two-layered, forming textura angularis, outer stratum 30–42μm thick, 8–15 layers of polygonal yellow brown to brown melanized cells; inner stratum 15–25μm thick, 4–7 layers of elongated polygonal to flattened, hyaline cells, merging with the pseudoparenchyma of the venter. Necks lateral bending upward, 260–550μm long, 90–130μm wide, cylindrical, hyaline to yellow brown, ostiolar canal periphysate, periphyses up to 20μm long. Catenophyses consisting of chains of cells that are subglobose, ovate to elongated, up to 28μm wide. Asci 120–202 (x=159μm, n= 20) μm long, 25–38 (x=32μm, n=20) μm wide, 8-spored, clavate, with narrow long stalks, 40–65μm long, 4–9μm wide, thin-walled, persistent, without an apical apparatus, developing at the base of the ascoma venter on small-celled ascogenous tissue. Ascospores 24–32 (x=29μm, n=50) μm long (excluding appendages), 10–16 (x=13μm, n=50) μm wide (excluding appendages), broadly ellipsoidal, 1-septate, not constricted at the septum, hyaline, thin-walled, with bipolar apical appendages, at first cap-like and stiff, 13–16μm long, 2.5–3μm wide, rapidly unfurling in water into long, thin filaments.

Material examined: Saudi Arabia, Jizan city, Farasan Island, 16° 44′ 22 N 42° 4′ 41 E, on decayed wood of Avicennia marina at a mangrove stand, 8 March 2012, M.A. Abdel-Wahab (CBS H-22126 holotype); ex-type living culture, MF 1206. GenBank LSU: JX911896; SSU: JX911897.

Notes: Several genera with polar unfurling ascospore appendages were described from marine habitats including: Aniptodera, Ascosacculus, Gesasha, Halosarpheia, Magnisphaera, Natantispora, Oceanitis and Saagaromyces. Among these, Saagaromyces is characterized by hyaline to light brown ascomata; thin-walled, 1-septate, broadly ellipsoidal ascospores and thin-walled, persistent asci. However, the single character that distinguishes the genus is the large hamate polar appendages that are equal to or longer than half of the ascospore length and width (Kohlmeyer 1984; Pang et al. 2003). Saagaromyces mangrovei has smaller ascospores and asci than the other described species in the genus.

Fig. 1 Saagaromyces mangrovei (holotype). a Vertical section of ascomata b Magnified part of the vertical section of the ascomata showing the peridium structure and the periphysate neck c Ascomatal squash showing immature asci and catenophyses (arrowed) d Ascomatal squash showing mature asci. c, d Stained with toluidine blue. Scale bars: a=50μm, b-d=25μm.

Fig. 2 Saagaromyces mangrovei (holotype). a Mature ascus b–d Ascospores with different degrees of uncoiling for polar appendages. c, d Stained with toluidine blue. Scale bars: a=10μm, b–d=5μm.