Phallus purpurascens T.S.Cabral, B.D.B.Silva & Baseia

Cabral, Tiara S., Silva, Bianca DB., Martin, Maria P., Clement, Charles R., Hosaka, Kentaro & Baseia, Iuri G., 2019, Behind the veil - exploring the diversity in Phallus indusiatus s. l. (Phallomycetidae, Basidiomycota), MycoKeys 58, pp. 103-127 : 111-114

Phallus purpurascens T.S.Cabral, B.D.B.Silva & Baseia sp. nov. Figure 5

Diagnosis.

This species is characterised by its large basidiome (up to 200 mm), the indusium reaching 2/3 of the basidiome, the purplish volva and rhizomorphs and the thimble-like and strongly reticulated receptacle.

Holotype.

BRAZIL. Amazonas: Manaus (3.0615S, 60.0111W), 27 February 2014, Cabral TS (UFRN-Fungos 2808). GenBank accessions: MG678487 (ITS), MG678456 (nuc-LSU), MG678542 (atp 6).

Immature basidiomes whitish (N60A60M50) with purplish pigments (A10M10C10), globose to subglobose, up to 56 × 43 mm, growing gregariously. Fresh expanded basidiome up to 200 mm high. Receptacle up to 45 × 29 mm, thimble-like, flat at the apex with an apical pore; strongly reticulated surface, shallow reticulations up to 3.2 × 1.7 mm, white (N00A00M00). Pseudostipe up to 122 × 21 mm, cylindrical, spongy, white (N00A00M00); pseudoparenchymatous, composed of globose to elongate-ovoid cells, 37-65.5 × 22.5-48 µm, hyaline. Indusium well-developed, extending up to 2/3 of the pseudostipe, white (N00A00M00), up to 100 mm in length, attached to the apex of the pseudostipe; polygonal meshes up to 10 × 5 mm. Volva semi-hypogeous, white (N00A00M00) becoming purplish (A10M10C10) when exposed, with a smooth surface; formed by filamentous hyphae, septate, branched, hyaline, clamp connections present, 3.1-6.6 μm diameter; with crystal deposits in globose cells widely distributed amongst the hyphae, 17.5-38 × 20.5-35.7 μm. Rhizomorphs composed of at least two types of hyphae: filamentous thin-walled hyphae, with clamp connections; and thicker hyphae (3-6.5 µm) that seem to communicate with each other by pores on the inflated tips. Gleba olive-brown (N99A50M10), mucilaginous. Basidiospores cylindrical, smooth, 4.4-5 × 2.5-3.4 µm, hyaline in 5% KOH.

Habitat and Distribution.

on soil, in a fragment of upland secondary forest. It was found in the municipalities of Manaus (State of Amazonas, Brazil) and Sinop (State of Mato Grosso, Brazil).

Etymology.

with reference to the volva becoming purple.

Other specimens examined (paratypes).

Mato Grosso: Sinop, Parque Florestal de Sinop (11.8359S, 55.5008W), 7 November 2013, Cabral TS (SINOP26, SINOP27, SINOP28, SINOP30).

Notes.

This species is the most distinctive amongst our collections, mainly due to its large basidiome, the purplish volva and rhizomorphs and the strongly reticulated receptacle. Phallus rubrovolvatus (M. Zang, D.G. Ji & X.X. Liu) Kreisel is one of the largest white-indusiate species (up to 330 mm); it differs from P. purpurascens by the deep red volva, the fragile indusium, by larger reticulations on the receptacle and smaller spores (3.7-4 × 2-2.5 µm) ( Liu 1984, Calonge 2005). Additionally, in the phylogenetic analysis ( Figures 2 , 3 ), P. rubrovolvatus does not group with P. purpurascens , which confirms their separate identities. Phallus callichrous has an orange to pink receptacle, reddish-violet rhizomorphs and orange receptacle with pink margin ( Möller 1895, Kreisel and Hausknecht 2009), which differ from the white receptacle, purplish volva and rhizomorphs of P. purpurascens ; unfortunately, there is little information available for this Brazilian species ( Calonge 2005). Phallus multicolor (Berk. & Broome) Cooke is similar to P. purpurascens in the purplish volva and rhizomorphs, but it differs by the cream to orange indusium and the light yellow pseudostipe ( Lloyd 1909, Calonge 2005, Kreisel and Hausknecht 2009). Phallus indusiatus differs from P. purpurascens by the smaller basidiome, the hypogeous development of the immature basidiome and smaller spores (up to 4.1 × 2.2 µm), the well-developed indusium reaching the ground and the campanulate receptacle with wider reticulations ( Ventenat 1798). The phylogenetic analyses show specimens of P. purpurascens grouping in a clade with high support values (ITS tree: pp = 1, bs = 100%; CONC tree: pp = 1, bs = 98%), confirming its distinct identity.

Phallus purpurascens was found in a fragment of secondary forest, in an extremely threatened area of the Amazonian forest domain in the State of Mato Grosso, Brazil. This state was the second most deforested in Brazil in 2018 ( INPE 2018), meaning that species in this area may be suffering the consequences of habitat fragmentation, which is one of the main causes of decline in fungal species ( Courtecuisse 2008). Thus, this new species record shows the urgency of cataloguing fungal biodiversity of threatened areas, such as Neotropical forests.

Figures

Figure 2. Phylogenetic tree obtained by Bayesian analysis with ITS. Brazilian clades corresponding to the new species and P. indusiatus are indicated (the holotype of each species is in bold). Posterior probabilities and bootstrap values are on the nodes (pp / bs), values of pp <0.95 and bs <90 are not shown. The black dots indicate specimens under Phallus indusiatus deposited in GenBank and downloaded for this study.

Figure 3. Phylogenetic tree obtained by Bayesian analysis with concatenated data (ITS, nuc-LSU and atp 6). Brazilian clades corresponding to the new species and P. indusiatus are indicated (the holotype of each species is in bold). Posterior probabilities and bootstrap values are on the nodes (pp / bs), values of pp <0.95 and bs <90 are not shown (except for P. denigricans clade).

Figure 5. Phallus purpurascens SINOP 27, paratype. A Fresh basidiome B gregarious immature basidiome, with purplish pigments on surface C longitudinal section of an immature basidiome, showing the purplish volva and rhizomorphs. Phallus purpurascens UFRN-Fungos 2808, holotype. D Spores E rhizomorphs hyphae F pseudoparenchymatous hyphae from pseudostipe G hyphae from volva H crystals in globose cells found on volva. Scale bars: 20 mm (A-C), 20 µm (C-H).