Porina leptosperma Mull. Arg.

Porina cf. leptosperma Müll. Arg., Flora, Regensburg 66 (21): 333. 1883. Fig. 18 E, F Type. BRAZIL • Apiahy, J. I. Puiggari 1090 (holotype: G). Notes. New record for Madagascar. Porina leptosperma is a common but inconspicuous pantropical species of rainforest understories (Lücking 2008). The taxon is represented by a single specimen, 20274 C, from northern Madagascar. The specimen is broadly consistent with the published descriptions of P. leptosperma (Lücking 2008; McCarthy 2013). The 3 - septate ascospores, measuring (18.5 –) 21–26 (– 32) × (4.2 –) 4.9–5.9 (– 6.4) µm (n = 85), slightly exceed the previously published range of 14–24.5 × 3–4.5 µm. The thallus appears larger than previously described (Fig. 18 E) and more closely resembles the continuous, irregular thallus described by Lücking (2008) than the smaller, irregular patches described by McCarthy (2013). The subglobose, orange perithecia measure 0.15–0.2 mm (n = 17) in diameter, matching the previously reported morphology and size of 0.13–0.26 mm. The taxon was recovered within the Porina fusca clade in both mtSSU and ITS phylogenies (Figs 2, 3) and may represent the first sequenced specimen attributable to P. leptosperma. The specimen was associated with photobiont haplotype 33: 3 (Figs 4, 5), the only member of algal clade 33 characterised by angular-rounded, irregularly arranged cells. Overall, the specimen agrees closely with current morphological concepts of P. leptosperma; its larger thallus and broader ascospores, together with the absence of reliable type-linked sequences, preclude a confident assignment to P. leptosperma s. str. It is therefore retained as P. cf. leptosperma. Specimens examined. MADAGASCAR – Diego Suarez Prov. • Antsiranana, Region: Diana, District: Diego II, Commune: Joffreville, Forontany: Morafeu, National Park of Montagne d’Ambre, along trail from summit Olioly to small dam near camp Gîte des Roussettes, through moist montane forest, 12°32'34"S, 49°09'23"E, alt. 1242 m, 8 Oct. 2014; Ertz 20274 C (BR, TAN).