Calvatia oblongispora sp. nov. from Brazil, with close affinities to C. sporocristata from Costa Rica

A new species of Calvatia from Manaus in Amazonas State, Brazil, is proposed, which is very close to Calvatia sporocristata, recently described from Costa Rica. The two species have been compared macroscopically and examined using light and scanning electron microscopy. The proposed new species, C. oblongispora, possesses a distinctly two-layered exoperidium consisting of a hyphal outer layer and an inner pseudoparenchymatous layer. This contrasts to the single pseudoparenchymatous exoperidium possessed by C. sporocristata. A table comparing the main exoperidial, basidiospore, and capillitial differences between both species is provided.


Introduction
During a taxonomic survey of the species of Calvatia from South America, a collection from INPA, at Manaus, State of Amazonas, Brazil, was studied that we were unable to match with current reference publications (Zeller & Smith 1964Kreisel 1992, 1994Lange 1990Lange , 1993Moreno & al. 1996Ochoa & al. 1998Calonge & al. 2003. In their study of phylogenetic relationships among the Lycoperdaceae from North Europe, Larsson & Jeppson (2008) included six species of Calvatia in their sequence data analyses. [The current (10 th ) edition of the Dictionary of the Fungi (Kirk & al. 2008) recognizes about 40 taxa.]

Discussion
The type and only specimen studied is a single, ill-preserved specimen, easily broken on handling. The fact that the gleba is not homogeneously coloured suggests that the material was immature upon collecting. Under the LM the gleba also exhibits hyaline hyphal elements, possibly from the central tissue. The specimen is characterized by its felty, very fragile peridium, presence of a distinct cellular subgleba, capillitium with medium to large pores, oblong to ellipsoid, echinulate spores under the LM, which appear with spines arranged forming cristae and greatly resembling those of Calvatia sporocristata Calonge (Calonge et al. 2003). The ends of the capillitium threads coincide with those of C. cretacea (Berk.) Lloyd and C. horrida M. Lange (Lange 1990). According to Kreisel (1994) the new species would belong to Calvatia section Calvatia, which contains 10 species so far. However, the spore ornamentation of our collection does not match any of these. Thus, we agree with Calonge et al. (2003) to include this new taxon within section Sporocristata Calonge.
On the other hand, the main differences between the new species C. oblongispora and C. sporocristata are as follows: The exoperidium of C. oblongispora shows two layers, an outer hyphal, and an inner one of pseudoparenchymatous structure, while in C. sporocristata it has only one pseudoparenchymatous layer (Table 1).
The spores are morphologically similar in both but slightly bigger in C. oblongispora and cylindrical (Fig. 1a), whereas they appear elliptical in C. sporocristata (Figs. 1b, 1c). The capillitium shows irregular and variously sized pores in C. oblongispora, while pores are lacking in C. sporocristata (Table 1).
Less closely related but similar species include Calvatia longicauda (Henn.) Lloyd and C. agaricoides Dissing & M. Lange, both of which show an agaricoid shape with a distinct pseudostipe, two-layered exoperidium, and spores that are ellipsoid and echinulate spores but have spines not aligned in crests (Dissing & Lange 1962). A third similar species, C. ochrogleba Zeller, has the same morphology but produces spherical, spiny, spores without crests (Zeller 1947Zeller & Smith 1964.
In conclusion, we consider that the combination of a two-layered exoperidium, spores with spines aligned in crests, and a pored capillitium supports the proposal of C. oblongispora as a new species.