Survey of bryophytes in Serra da Canastra National Park , Minas Gerais , Brazil

Serra da Canastra National Park is located in southwestern Minas Gerais State and contains several phytophysiognomies of the Brazilian Cerrado. To date, no study on bryophytes has been conducted in this area and the present study is the fi rst to be carried out in this major biological reserve of Cerrado located on the Brazilian Plateau. Th is study found 289 species of bryophytes, including mosses, liverworts, and one species of hornwort, representing fourtyone Brazilian endemic species and 56 new records for Minas Gerais State. Most species are widely distributed in Brazil, with only 16% having restricted distributions. Regarding worldwide distribution, 31% are Neotropical. Lejeuneaceae had the highest species richness among liverwort families with 53 species, whereas Sphagnaceae had the highest richness among moss families with 26 species. Phaeoceros laevis was the only hornwort species found in the park. Th is study contributes to the understanding of bryophyte species richness and distribution, and provides the worldwide and Brazilian distribution of the bryophyte fl ora of Serra da Canastra National Park, an important center for biodiversity conservation.


Introduction
Serra da Canastra National Park was created in order to protect the source of the São Francisco River, which is the watercourse arising in the huge chest-shaped plateau.Serra da Canastra divides two watersheds: the south portion is the beginning of the Paraná River and the north portion is the beginning of the São Francisco River (Souza & Costa 2011).
Th e predominant vegetation is represented by grasslands and rocky fields (campos rupestres) (Carvalho-Silva & Guimarães 2009), which ensure a high degree of endemism since they occur in areas with particular ecological conditions infl uenced by geographic isolation and biotic and abiotic factors (Harley & Simmons 1986;Giulietti et al. 1987;Pirani et al. 1994;Stannard 1995).Since the park is open to visitors there is some anthropic disturbance, such as the installation of unpaved roads and buildings; nevertheless, there is a relatively high degree of endemism among some angiosperm species, and so a great need for the permanent preservation of the area as a conservation unit (Romero & Nakajima 1999).
Floristic surveys conducted in areas of Minas Gerais that are similar to Serra da Canastra include Yano & Carvalho (1995) who found 46 species in Serra da Piedade; Yano & Peralta (2009) who found 42 species of mosses and hepatics in the Grão-Mogol mountains; Yano & Peralta (2011a) found 114 species in Serra de São José at the city of Tiradentes; Yano & Peralta (2011b) found 237 species in Serra do Cipó; Luizi-Ponzo et al. (2013) found 209 species in Ibitipoca State Park and, recently, Souza & Câmara (2015) who studied the mosses of gallery forest in Serra do Cipó National Park.Th ese works contain relevant fl oristic data and are useful in the 1 Instituto de Botânica, Núcleo de Pesquisa em Briologia, P.O.Box 68041, 04045-972, São Paulo, SP, Brazil identification of some species.Furthermore, they provide species lists and document the location of bryophytes in these regions, resulting in knowledge of about 766 species of bryophytes in Minas Gerais State (Costa & Peralta 2015).
These works notwithstanding, floristic inventories of bryophytes in mountainous areas of Minas Gerais are still sparse considering the extensive area of the Cerrado domain in the state and in comparison to other terrestrial plant groups.Therefore, Serra da Canastra is an interesting area with great potential for the study of bryophytes (Costa et al. 2011).Furthermore, there are few compilations of the occurrence of Brazilian bryophytes among phytogeographic domains that also include their distribution within Brazil and worldwide.
To date there has been no study of the bryophytes in this significant biological reserve of Minas Gerais.Therefore, this study aimed to carry out a floristic survey of the bryophytes in Serra da Canastra National Park by analyzing bryophyte species richness, occurrence among phytogeographic domains and Brazilian and worldwide geographical distributions.

Study area
The Serra da Canastra National Park is situated on a mountain range located in southwestern Minas Gerais and encompasses parts of the municipalities of Sacramento, São Roque de Minas and Delfinópolis (20°00'-20°30'S and 46°15'-47°00'W).It contains 71,525 ha with average altitude ranging from approximately 800 to 1,200 m, with the highest point of the park being Serra Brava at 1,496 m.The average temperature is around 17°C in the winter and 23°C in the summer, but varies between higher and lower regions.Average annual rainfall ranges from approximately 1,300 to 1,700 mm, with most rainfall being concentrated from December to February (IBDF 1981).

Data collection and identification
Twenty samples from the study area were found in SP herbaria (Holmgren et al. 1981) and four one-week long expeditions were made to the park during to make collections in 2012 to 2014.
The list of species is organized in alphabetical order by family, then genus and then species, and provides the Brazilian geographical distribution as proposed by Valente & Pôrto (2006), who considered as "rare" those bryophythes occurring in one to four Brazilian states; as "moderate" those occurring in five to nine states; and as "wide" those occurring in ten or more Brazilian states.The distribution and biogegraphical domains followed Gradstein & Costa (2003), Yano (2008), Forzza et al. (2010), Costa et al. (2011) and Costa & Peralta (2015).

Species richness
One thousand one hundred and seventy-seven (1,177) samples were analyzed, with 722 samples of mosses (Bryophyta), 454 of liverworts (Marchantiophyta) and only one of a hornwort (Anthocerotophyta).Two hundred and eight-nine species of bryophytes were found, representing 128 genera and 57 families, accounting for approximately 38% of the species estimated for the state and 19% for the country (Tab. 1) (Costa & Peralta 2015).
Other studies in high altitude areas of Minas Gerais State, also found greater species richness of mosses than liverworts (Yano & Carvalho 1995;Yano & Peralta 2009;Yano & Peralta 2011a;b;Luizi-Ponzo et al. 2013).This is probably due to mosses having more morphologically complex gametophytes and sporophytes, which increases the possibilities for occupation of varied environments.Furthermore, mosses are more resistant to dessication than most of liverworts (Goffinet et al. 2009), thereby they can occur and predominate in areas where the availability of water is more restricted, and conditons of moisture and rainfall are relatively low, unlike the Atlantic Forest where the species richness of mosses is lower than that of liverworts (Gradstein et al. 2001).
Sphagnaceae was the most species rich moss family and, in including a number of Brazilian endemics and new occurrences, of significant importance to Serra da Canastra (Tab.1).Although this family is often associated with watercourses and water-soaked soils (Schofield 1985), it can also be found on rocky and extremely dry surfaces, with soil and rocks as their main substrates.
Leucobryaceae (21 species) and Bryaceae (13 species) were the bryophyte families with the greatest richness in high altitudes areas in Minas Gerais (Yano & Carvalho 1995;Yano & Peralta 2011b).This is supported by the fact that representatives of these families are constantly found in mountain regions (Gradstein et al. 2001).These families have in common an acrocarpous growth habit of the gametophyte, and are found in more exposed areas, such as the vast rocky fields of the Cerrado (Bastos & Vilas Bôas-Bastos 2008).Sematophyllaceae and Hypnaceae were the most represented pleurocarpous moss families and are widely distributed worldwide, mainly in the tropics, and are very diverse morphologically (Buck 1998;Ramsay et al. 2002;Ireland & Buck 2009).
The family of liverworts with the greatest species richness was Lejeuneaceae, which has 56 genera and 285 species in Brazil (Costa et al. 2015).In the present study the family accounted for 47% of the liverworts found, and has frequently been among the most abundant families of liverworts in other studies on mountainous areas of Minas Gerais (Yano & Carvalho 1995;Yano & Peralta 2009;Yano & Peralta 2011a;b;Luizi-Ponzo et al. 2013).This family is known to have originated relatively recently during bryophyte evolution, and includes many independent diversifications resulting in great morphological variation, several forms of substrate occupation and different taxonomic conceptulizations which have resulted in this great diversity presented by the family (Groth-Malonek et al. 2004).
Phaeoceros laevis was the only species of hornwort (Anthocerotophyta) found in Serra da Canastra National Park, where it was collected growing on rocks among rocky outcrops near streams of the lower portion of the Casca D'anta waterfall.Only one of the previous studies in Minas Gerais also found this species (Yano & Peralta 2011b).In Serra do Cipó, this species was found growing on soil and was associated with the thallose liverwort Fossombronia porphyrorhyza.

Substrate colonization
Regarding substrate colonization, a predominance of rupicolous bryophytes was observed in Serra da Canastra National Park.Among the 1,177 bryophyte samples collected, 406 were on rocky substrates, 356 were corticolous, 349 terrestrial, 27 epiphyllous and 18 epixylic (Fig. 1).Mosses that were found growing submerged or under the water were considered aquatic and, with other different substrates types (termite mound, litter), represented 21 samples (Fig. 1).
In other studies conducted in Minas Gerais, species of bryophytes showed a preference for corticolous substrates (Yano & Peralta 2011b;Luizi-Ponzo et al. 2013), such as growing on the trunks of living trees.In their study focusing on gallery forests of Serra do Cipó, Souza & Câmara (2015) also observed a preference for corticicolous substrates and explanained this finding on the abundance of this substrate in the area, but concluded that ecological studies are needed to verify this hypothesis.Following this reasoning, the large amount of rupicolous species in Serra da Canastra National Park is likely due to the presence of many rocks, especially in areas near waterfalls and in rocky fields, since the methodology of collection was the same for all vegetation types.However, as with the gallery forest of Serra do Cipó, ecological study is necessary to conclude this hypothesis.
Our study collected 27 samples (Fig. 1) of epiphyllous bryophytes, which are those species that grow on living leaves.The family Lejeuneaceae was the only family found growing on this type of substrate in Serra da Canastra National Park.According to Gradstein et al. (2001), this family can colonize many types of substrates, but the epiphyllous habit is common in preserved native areas, which highlights the exigency for the protection of Serra da Canastra National Park.

Worldwide and Brazilian distribution
Concerning worldwide distribution, a predominance of Neotropical species was observed in Serra da Canastra National Park, with 89 species.This was followed by 61 tropical America species, 41 Brazilian endemic species, 39 cosmopolitan species, 33 pantropical species and 26 with disjunct distributions with the Andes, Africa and other countries of South America (Fig. 2) (Tab.1).
We found 56 new species for the state of Minas Gerais, which represents 19% of the total bryophyte species collected.Among these, 36 species (64%) have a "rare" distribution in Brazil, 13 (23%) a "moderate" distribution and seven (13%) a "wide" distribution (Tab.1).Campylopus densicoma was first recorded for Minas Gerais and has a "rare" distribution, being previously found only in Rio de Janeiro, and is considered an endangered species (Costa et al. 2013).
The data obtained through this study show that the Serra da Canastra National Park is an important area for bryophyte diversity and conservation, especially since there remain many species to be discovered.
Moreover, the present study also found some Brazilian endemic species, which had so far been only recorded for the Amazon Rainforest domain, such as Cololejeunea contractiloba and Lejeunea erostrata of Marchantiophyta, and Sphagnum dimorphophyllum for Bryophyta (Costa et al. 2011).Perhaps these results are due to gaps in collections of material from areas of the Brazilian Highlands, such as Serra da Canastra (Gradstein et al. 2001;Costa et al. 2011), which is reflected in the great number of new occurrences observed in this study.
The two species endemic to Serra da Canastra National Park, Itatiella denudata and Sphagnum geraisense, were recollected during this study reinforcing the importance of maintaining Serra da Canastra National Park for the conservation of endemic species (Romero & Nakajima 1999) as well as the great diversity of other bryophytes found in this study.
This study has provided new information on bryophyte richness, occurrence, occupied phytophysiognomies and worldwide and Brazilian distributions, particularly those occurring in mountain areas of the Brazilian Highlands, where more floristic studies on bryophytes are needed.The large number of species found in the park (289 spp.), accounting for approximately 38% of the species known in Minas Gerais and 19% in Brazil, the new records for this state (56 spp.) and the number of Brazilian endemic species (41 spp.), stress the importance of performing floristic inventories in Brazil and maintaining Serra da Canastra National Park for conservation as a biological reserve.(Seção de Briologia) for the support of all the necessary equipment throughout the study.We also acknowledge CAPES for financial support and ICMBIO for the license n° 39601-2 granted collecting in the area.

Figure 1 .
Figure 1.Percentage of samples obtained from each substrate.

Figure 2 .
Figure 2. Percentage of bryophytes species obtained and their worldwide distribution.