Small but important: The woody vegetation communities on the sandstone outcrops of Teyú Cuaré (Misiones, Argentina)

Abstract

Rock outcrops are commonly harsh environments that maintain important components of biodiversity because they are inhabited by endemic or relictual species. We studied the diversity and structure of the woody plant of rupestrian vegetation located in the San Ignacio department (Misiones, Argentina), and evaluated the beta diversity with respect to other neighbor vegetation formation (i.e. forest and savanna). We found 32 species, most of them were arboreal nonetheless of small size. Qualea cordata (Mart.) Spreng., Monvillea euchlora Backeb., Ocotea lancifolia (Schott) Mez and Myrciaria delicatula (DC.) O.Berg were the most important in the community structure. Rupestrian vegetation showed an intermediate woody species diversity compared to nearby forests and savannas. We found a high beta diversity between rupestrian formation and the other physiognomies mainly established by richness difference. Rock environments are high-priority conservation level because their singular plant communities inhabit specific edaphic and geomorphic conditions, occurring only in a restricted geographical range.