In search of generality: Revised distribution data and regionalization of Cerrado endemic tetrapods

Abstract

AbstractAimTo search for a general regionalization pattern using verified records of endemic terrestrial vertebrates. To test previous hypotheses of congruent distribution patterns for Cerrado biotas. To study the role of elevation as a driver of endemism and distribution in the Cerrado region.LocationCerrado domain, central South America.TaxonTetrapoda.MethodsWe used a species occurrence matrix to implement a biotic element (BE) analysis to test for non‐random spatial congruence of raw distributions of Cerrado endemic amphibians, reptiles, birds and mammals. We implemented a Kruskal–Wallis test on elevational records to classify species as occurring predominantly in plateaus or depressions, and to classify all delimited BEs in such categories.ResultsWe compiled and revised 13,800 unique distribution records of 340 Cerrado endemic tetrapods and detected a significant, non‐random co‐distribution pattern formed by 29 BEscomprising 182 species, corroborating the first general prediction of the vicariant model. Most BEs were composed of at least three vertebrate groups, reflecting general tetrapod endemism patterns. Congeneric species were segregated among different BEs, corroborating the second prediction of the vicariant model. Our regionalization scheme was broadly congruent with previous results and revealed three previously undetected areas. Most (89%) partial or restricted BEs are clearly segregated in elevation, and we recognized 14 ‘Plateau units’ and 12 ‘Depression units’.Main ConclusionsOur results support an emergent consensual biotic regionalization pattern in the Cerrado. We also revealed three novel regions and complex biogeographical patterns. The clear altitudinal segregation among BEs validates previous hypotheses on the role of geomorphological changes in shaping Cerrado and Neotropical endemism patterns. Our recovered units should serve as a template for the description of new taxa, for delimiting poorly studied ranges, and for guiding urgent conservation action in the richest and most imperilled tropical savanna in the globe.