The disjunct distribution of Cladonia dimorphoclada Robbins (Ascomycota: Cladoniaceae): fi rst record in South America

(The disjunct distribution of Cladonia dimorphoclada Robbins (Ascomycota: Cladoniaceae): fi rst record in South America). Previously known only from the North and Central America, the lichenized fungi Cladonia dimorphoclada Robbins is recorded for the fi rst time in South America. The specimens were found growing on soil, in an open area at 1695 m alt., in Southern Brazil. We present a distribution map, fi gures, and comments.

Previously, Cladonia dimorphoclada was only known from the Eastern United States (e.g.Ahti 1973, Flenniken 1999, Hansen & Freeman 2003, Thomson 2003, Harris 2004), and also rarely found in southern Mexico, and western Cuba (Ahti 2000).In this paper, we report the occurrence of C. dimorphoclada for the fi rst time in South America, more precisely from the Southern region of Brazil.

Material and methods
Specimens were examined using standard techniques, stereomicroscope, and light microscope.Sections of the thallus and apothecia were mounted in water.Chemical analyses were done according to Huneck & Yoshimura (1996) and Orange et al. (2001).The distribution map (fi gure 1) was produced in QGIS Software 2.0.1, according to a tutorial developed by Calegari et al. (2016).
Distribution and ecology: according to Ahti (2000), in the United States Cladonia dimorphoclada occurs mainly on sandy soils, in Mexico on sandstone rocks, and in Cuba on the coastal white sand.In Brazil, specimens were found growing on top of a rocky outcrop in an open field (figure 3).
Cladonia dimorphoclada can be differentiated from other Brazilian Cladoniae by the few branched thalli with closed axils, the presence of a rudimentary  cortex and stereome intermixed with medulla, and the production of usnic acid as the only secondary compound.

Figure 1 .
Figure 1.Distribution map of Cladonia dimorphoclada.Green circles: previous records.Red star: new record.

Figure 3 .
Figure 3. Habitat where Cladonia dimorphoclada was found in Southern Brazil, Municipality of Urubici, São Joaquim National Park.