Melaspilea lekae Brackel & Kalb, 2012

Kalb, Klaus, Buaruang, Kawinnat, Mongkolsuk, Pachara & Boonpragob, Kansri, 2012, New or otherwise interesting Lichens. VI, including a lichenicolous fungus, Phytotaxa 42, pp. 35-47 : 44-45

Melaspilea lekae Brackel & Kalb sp. nov. ( Fig. 2J ) Mycobank MB 564185

Fungus lichenicola sicut Melaspilea diplasiospora (Nyl.) Müll. Arg. , sed ascosporis minoribus et Sarcographa labyrinthica (Ach.) Müll. Arg. hospite differt.

Etymology:—The new lichenicolous fungus is named in honour of Prof. Leka Manoch in recognition of her numerous contributions to Thai mycology.

Type:— THAILAND. Trat Province: Muang District, near Ban Nam Chieo , in a ± disturbed mangrove forest on Sarcographa labyrinthica , ± 3 m, 12°10’25’’ N, 102°28’37’’ E, 25 February 2011, K. Kalb & P. Mongkolsuk (holotype RAMK, isotype hb. Kalb 38860) .

Ascomata lichenicolous on thallus and ascomata of Sarcographa labyrinthica , 0.2–0.4 × 0.1–0.2 mm, lirellate to ellipsoid, occasionally branched, solitary or irregularly aggregated, superficial with an exposed, reddish brown disc, leaving a black outline when eroded. Exciple laterally carbonized, 10–18 µm thick, ± absent below the hymenium. Hymenium colourless, ca. 60 µm high, hypothecium colourless to brownish, 8–13 µm high, both KOH-, I-, K/I-. Paraphyses septate, 2–3 µm wide, not or only sparsely branched with obovate terminal cells, 4–5 µm wide, these (or the two uppermost cells) with a granular brown pigment, K–. Asci clavate, ca. 35–40 × 13–20 µm, 4–8-spored, KOH-, I-, K/I-. Ascospores 1-septate, sole-shaped, distictly constricted at the septum, finely verruculose, pale to medium brown, 14–17 × 7–8 µm.

Notes:—Previously only four Melaspilea species were known to grow on Graphidaceae , namely M. diplasiospora on Graphis elegans (Borrer ex Sm.) Ach. , M. epigena Müll. Arg. on Reimnitzia santensis (Tuck.) Kalb , M. epigraphella (Nyl.) Müll. Arg. on Acanthothecis consocians (Nyl.) Staiger & Kalb and M. lentiginosa (Lyell ex Leight.) Müll. Arg. on Phaeographis dendritica (Ach.) Müll. Arg. All differ in the host and especially the ascospore dimensions. While the ascospores of M. diplasiospora are considerably larger (19.5–32 × 9.5–16 µ m) than those of M. lekae , they are smaller in M. epigena (10–12 × 5 µ m), M. epigraphella (9–11 × 3.5–4.5 µm) and M. lentiginosa 10–13.5 (–16) × 5–7.5 µm.

Figures

FIGURE 2. G. Malmidea incrassata (holotype), thallus with apothecia; Scale: 1.5 mm. H. Malmidea reunionis (holotype), thallus with apothecia; Scale: 2 mm. I. Malmidea tratiana (holotype), thallus with apothecia; Scale: 0.5 mm. J. Melaspilea lekae (holotype), ascocarps on thallus of Sarcographa labyrinthica; Scale 0.5 mm. K–L. Stirtonia rhizophorae (holotype), K. thallus with ascigerous zones; Scale: 1 mm. L. ascospore; Scale: 13 µm.