Keissleriella tamaricicola Thambugala, Camporesi & K.D.Hyde, sp. nov. Index Fungorum number: IF552095

Etymology: The species epithet Btamaricicola^ refers to the host genus Tamarix on which the holotype occurs.

Holotype: MFLU 14–0597

Saprobic on branches of Tamarix species. Sexual morph: Ascomata 160–300 μm diam. × 130–240 μm high (x = 210 × 167 μm, n = 7), solitary or in small groups, scattered, immersed under a blackened clypeus, globose or subglobose, dark brown to black, coriaceous, fused to the host tissue, ostiolate. Ostiole papillate, slightly protruding, with apical dark brown, short setae. Peridium 8–24 μm wide, composed with dark brown to black, cells of textura angularis, cells towards the inside lighter and somewhat flattened, at the outside, darker, fusing with host tissues. Hamathecium comprising 1–2.5 μm wide, branched, septate, cellular pseudoparaphyses. Asci 78–100 × 8–11.6 μm (x = 88.5 × 9.8 μm, n = 20), 8-spored, bitunicate, cylindric-clavate, slightly curved, with short bulbose pedicel, apically rounded, with an ocular chamber. Ascospores 12.5–15.2 × 3.8–5.6 μm (x = 13.7 × 4.7 μm, n = 20), hyaline, broadly fusiform, 1-septate, cells of unequal size, deeply constricted at the septum, widest at the middle and tapering towards the narrow ends, straight or slightly curved, with small guttules smooth-walled. Asexual morph: Conidiomata 200–430 μm diam. × 190–410 μm high (x = 326 × 306 μm, n = 5), pycnidial, scattered or clustered, gregarious, semi-immersed to superficial on PDA, globose to subglobose, surrounded by vegetative hyphae. Conidiomata wall 15–32 μm wide, composed of several layers of black to hyaline pseudoparenchymatous cells of textura angularis. Conidiophores aseptate, hyaline, mostly reduced to conidiogenous cells. Conidiogenous cells 3.5–7.6 × 1.2–3.4 μm (x = 5.7 × 1.9 μm, n = 20), enteroblastic, phialidic, single, discrete, determinate, doliiform to cylindrical or ampulliform, hyaline, arising from basal stratum. Conidia 2.5–4.8 × 1.7–2.9 μm (x = 2.5 × 2.1 μm, n = 60), one-celled, ellipsoidal, with rounded to obtuse ends, hyaline, smooth-walled.

Culture characteristics: Ascospores germinating on PDA within 24 h and germ tubes produced from one or both ends. Colonies growing on PDA reaching 17 mm diam. After 16 days at 25 °C, circular, flat, moderately dense, surface white, smooth surface with entire to slightly undulate edge, asexual morph produced after 2 weeks.

Material examined: ITALY, Province of Forlì-Cesena, Ravaldino in Monte – Forlì, on dead branches of Tamarix gallica L. (Tamaricaceae), 15 January 2014, E. Camporesi IT 1458 (MFLU 14–0597, holotype), ex-type living culture MFLUCC 14–0168, ICMP 20704; ibid. (GZAAS, isotype).


FIG Keissleriella tamaricicola (holotype-sexual morph) a, b Appearance of ascomata on the host surface c, d Vertical sections through ascomata e Peridium f Pseudoparaphyses g-j Mature and immature bitunicate asci k-n Ascospores. Scale bars: c, d = 100 μm, e = 50 μm, f = 10 μm, g-j = 25 μm, k- n = 5 μm

FIG. Keissleriella tamaricicola (asexual morph from ex-type living culture) a Appearance of conidioma on PDA b Vertical section through conidioma c Conidiomatal wall d Conidiophores and conidiogenous cells producing conidia e Conidia. Scale bars: b = 100 μm, c-e = 10 μm