New distributional data on Geastrum ( Geastraceae , Basidiomycota ) from Brazil

(New distributional data on Geastrum (Geastraceae, Basidiomycota) from Brazil). Th e data presented in this article are the results of fi eld collections and the analysis of fungal specimens deposited in the URM Herbarium. Th e fi eld trips were carried out in four Atlantic Forest remnants in the state of Pernambuco, between June 2008 and May 2009. Th e revision of specimens housed in the URM was restricted to the Brazilian exsiccatae. Geastrum specimens were examined macroand microscopically following the traditional methodology used in the group. Geastrum javanicum and G. lloydianum are new records from the Northeastern Region of Brazil. Eight species are new records from the following states: Pará (G. fi mbriatum), Ceará (G. lloydianum), Paraíba (G. fi mbriatum, G. javanicum, G. schweinitzii and G. entomophilum), Pernambuco (G. lageniforme and G. triplex) and Rio de Janeiro (G. javanicum). In this article we present full descriptions for ten species of Geastrum with pictures and an identifi cation key.


Introduction
Geastrum species, commonly known as 'earthstar' fungi, are easily recognized in the fi eld by their exoperidium, which opens into a stellate shape.Some species, however, are found growing on rotten wood.Th e genus is characterized by an exoperidium divided into two or three layers, an endoperidium with or without a stalk, opening by an apical pore surrounded by an area called the peristome.Th e gleba is composed of abundant capillitium and basidiospores.(Ponce de León 1968, Sunhede 1989, Domínguez de To-ledo 1996, Kasuya et al. 2009).Currently, it is accepted that geastroid species are related to gomphoid/phalloid fungi (Hosaka et al. 2006).
Th e genus is frequent in the tropics and many herbarium collections registered under the name Geastrum have never been reviewed by specialists.Interesting data were published (Pereira et al. 2008, Gomes-Silva & Gibertoni 2009) aft er revisions of fungal exsiccatae deposited in the URM Herbarium (Holmgren & Holmgren 1998), including data on gasteromycete taxonomy (Drechsler-Santos et al. 2008, Trierveiler-Pereira & Baseia 2009b).Th is herbarium, created in 1954, currently preserves more than 80.000 collections, the largest fungal collection in Latin America (Maia 2003).
Th is work aimed to contribute to the knowledge of Geastrum species distribution in Brazil, based on fi eld collections and a review of herbarium material.
Th e review of Geastrum material deposited in the URM Herbarium was restricted to Brazilian exsiccatae.
A taxonomic study was performed by observing macro-and microscopic features according to Miller & Miller (1988) and Sunhede (1989).The basidiomata and endoperidium were measured including the size of the peristome.Colors were coded according to Kornerup & Wanscher (1978) and referred to dry material, unless otherwise stated.Spore measurements included surface ornamentation.
Vouchers were deposited in the URM, but not all the examined material is listed in the results.Some collections were compared to specimens deposited in MA-Fungi (Holmgren & Holmgren 1998).

Results
During this survey in the Atlantic Forest remnants in the state of Pernambuco, one hundred and forty-seven Geastrum specimens were collected, corresponding to nine species.

Geastrum hirsutum
Material Taxonomic remarks -Th is species was originally described based on Brazilian specimens and its most important characteristic is the presence of golden yellow hairs on the external layer (Baseia & Calonge 2006).Specimens of G. hirsutum grow in habitats similar to those of G. schweinitzii, but the latter usually produces smaller basidiomata.Geastrum hirsutum was originally described growing on termite nests, but all specimens collected for this work were found growing on rotten wood.Immature basidiomata globose to subglobose, with or without a pointed apex, 1.3-2.1 cm high × 1.1-2.0cm diam., external layer light orange (KC 5A5) to yellowish brown (KC 5D5), velutinous due to the presence of conical fascicles of hyphae up to 0.7 cm high × 0.5 cm diam.Expanded basidiomata 1.7-2.9cm high × 1.3-5.1 cm diam., sometimes with a short stipe up to 3.0 cm high.Exoperidium split into 5-7 rays, saccate, non-hygroscopic; mycelial layer not persistent; fi brous layer orange white (KC 5A2), macroscopically similar to the external layer of immature basidiomata, fi brous layer hyphae more or less straight, solid or with very narrow lumen, hyaline to slightly yellowish, 3-4 μm diam.; pseudoparenchymatous layer greyish orange (KC 5B4) to brownish orange (KC 5C4) when fresh, then greyish brown (KC 5D3) when dry, pseudoparenchymatous hyphae round, yellowish, 20-45 × 23-35 μm.Endoperidium greyish brown (KW 5D3) to yellowish brown (KW 5E4), globose, subglobose to depressed-globose, 0.7-1.7 cm high × 1.2-1.8cm diam., sessile; peristome concolor or slightly darker than endoperidium, fi brillose, not delimited, up to 1.5 mm high.Capillitial hyphae straight to more or less sinuous, solid or with very narrow lumen, yellowish brown to olive brown, 2-7 μm diam.Basidiospores globose, brownish, with more or less columnar ornamentation, 4-5 μm diam.Growing on a white subiculum on rotten wood.

Geastrum lageniforme
Material examined -BRAZIL.Pernambuco: Taxonomic remarks -Th is species is very similar to G. saccatum.Both species have saccate basidiomata, sessile endoperidium, fi brillose and delimited peristome.Geastrum lageniforme usually has longer and more slender rays and longitudinal ridges in the external layer.However, G. saccatum may also have such ridges.According to Sunhede (1989), the two species can be distinguished by the presence of clamped hyphae in the external mycelial layer, which only occur in G. lageniforme.Th ese hyphae were observed in the examined material, but they are not always easy to fi nd.Ponce de León (1968) considered G. lageniforme a synonym of G. indicum (Klotzsch) Rauschert.Rick, Brotéria 5: 26. 1906.
Geastrum badium Pers.(= G. elegans Vittad.) is a very similar species, but it has involute rays, sessile endoperidium, and lacks apophysis.Ponce de León ( 1968) reported that G. badium has hygroscopic basidiome and endoperidial body with granular surface.Leite et al. (2007a) recorded G. elegans from Pernambuco; however, a careful analysis of the material revealed that it actually corresponds to G. lloydianum.

Discussion
Macroscopic features are very important for the identifi cation of Geastrum specimens, since the species are nearly microscopically identical when observed using light microscopy.Th e importance of macroscopic data to delimit species can be noticed in identifi cation keys (Ponce de León 1968, Calonge 1998, Sunhede 1989, Bottomley 1948, Soto & Wright 2000, Baseia et al. 2003).
Herbarium material is sometimes very diffi cult to determine, due to the lack of information and the poor preservation condition of important macrostructures.Th erefore, some recommendations are given on collecting and improving the herborization quality of Geastrum specimens: 1) include notes about the substrata where the specimens were collected.Geastrum species usually grow on very specifi c habitat; 2) when collecting, pay attention to the surroundings and look for immature basidiomata.Th ey are oft en subglobose to pyriform, and may be totally or partially hypogeous (sometimes hard to fi nd); 3) basidiomata of some species lose their external layer at maturity, as in G.hirsutum and G. albonigrum Calonge & Mata.In this case, external layer characteristics are decisive in identifying these two species.When collecting, pay attention around mature basidioma and try to see if the external layer has peeled off ; 4) when drying the material, pay special attention to the peristome.It will be impossible to analyze the peristome, and thus identify the species, if it becomes covered by folds from the endoperidium.Materials must be dried at low temperatures (25-30°C) for 24-48 hours.