Aurantiporus tropicus (I. Lindblad & Ryvarden) Y. C. Dai, Xin Zhang, Vlasák, Ghobad-Nejhad & Yuan Yuan comb. nov. Hapalopilus tropicus I. Lindblad & Ryvarden, Mycotaxon 71: 342 (1999) (Basionym) Description. See Lindblad and Ryvarden (1999). Ecology and distribution. Growing on dead deciduous wood. Known from tropical wet forests in Costa Rica. Notes. Hapalopilus mutans was first described as Polyporus mutans from New York, USA, and was recognized by resupinate, colorful basidiomata with a reddish coloration in KOH solution (Lowe 1966; Gilbertson and Ryvarden 1986). Hapalopilus tropicus was originally described from the tropical forests of Costa Rica, and unlike the other Hapalopilus species, it is not reactive in KOH solution (Lindblad and Ryvarden 1999). However, Hapalopilus tropicus mostly resembles H. mutans by having resupinate, colorful basidiomata that turn red upon bruising, dense agglutinated tubes, shrinking and darkening upon drying, and a monomitic hyphal system with ellipsoid, smooth, thin-walled basidiospores (Lowe 1966; Gilbertson and Ryvarden 1986; Lindblad and Ryvarden 1999). However, according to the present study (see discussion), the above morphological characteristics fit the definition of Aurantiporus. Moreover, our phylogeny (Fig. 1) confirms that Hapalopilus mutans and H. tropicus grouped together with Aurantiporus roseus within the Aurantiporus s. str. clade, which was distant from H. rutilans (the type of Hapalopilus). Thus, the above combinations are proposed.

Published as part of Zhang, Xin, Zhou, Hong-Min, Ghobad-Nejhad, Masoomeh, Liu, Hong-Gao, Vlasák, Josef, Dai, Yu-Cheng & Yuan, Yuan, 2024, Molecular and morphological data reveal two new polypores (Polyporales, Basidiomycota) with reddish brown to orange basidiomata from China, pp. 75-94 in MycoKeys 107 on pages 75-94, DOI: 10.3897/mycokeys.107.126176