Porina rubentior Mull. Arg.

Porina rubentior (Stirt.) Müll. Arg., Flora, Regensburg 66 (2): 26. 1883. Fig. 18 B Type. BRAZIL • Trail (lectotype: BM, fide R. Lücking, Bot. Acta 109: 259 (1996)). Notes. Porina rubentior is a pantropical species commonly found in shady rainforest understories or drier evergreen forests (Lücking 2008). It has previously been reported in Madagascar by Aptroot (2016). This taxon is represented by three examined specimens from northern and southern Madagascar (20277 H, 25411 F, and 25411 G), all of which agree well with the descriptions provided by Lücking (1996, 2008). The 3 - septate ascospores measure (15 –) 16–18.5 (– 19.5) × (2.2 –) 2.4–2.9 (– 3) µm (n = 16), consistent with the reported range of 14–21 × 2.5–3.5 µm. The lens-shaped, dark red to blackish red perithecia measure 0.15–0.2 mm (n = 8), matching both the reported morphology and dimensions of 0.15–0.2 (– 0.3) mm. In the mtSSU phylogeny, the specimens were recovered within the Phragmopeltheca clade and show very little genetic divergence from Neotropical P. rubentior accessions (Fig. 2). No rbc L sequence was recovered for this taxon, although the photobiont exhibits the morphotype with rectangular cells arranged in radiate plates. Overall, the close agreement between morphology and phylogenetic placement supports the confident assignment of these specimens to P. rubentior s. str. under the current species concept. Specimens examined. MADAGASCAR – Diego Suarez Prov. • Antsiranana, West of Sambava, Marojejy National Park, along trail from Camp Mantella to Camp Marojejia, rather dense humid evergreen lower montane forest, 14°26'07"S, 49°46'05"E, alt. ca. 650 m, 18 Oct. 2014; Ertz 20277 H (BR, TAN). – Toliara Prov. • ca. 26 km Northwest of Fort-Dauphin (Tolagnaro), National Park of Andohahela, South part of parcel 1, ca. 6.5 km West of the village of Malio, 24°56'24.1"S, 46°43'26.2"E, alt. 1000 m, dense humid forest, 01 Dec. 2019; Ertz 25411 F, 25411 G (BR, TAN).