RESUMO
Zetekella and Minitingis (Heteroptera, Tingidae) are morphologically similar genera, each comprising two species. The latter was already considered a junior synonym of the former, but was revalidated on the basis of the number of cephalic spines, projections on the paranotal edge, length of the rostrum, presence of an abdominal groove and distributional pattern. Here, a new species of Zetekella is described from Ecuador, the diagnoses for both genera reassessed, new records for Z.pulla and Z.zeteki reported, and a key to the species of both genera provided.
RESUMO
We suggested using parsimony analysis to study community evolution in terms of species composition and to apply these results in the context of forest fragmentation as a replacement for the so-called "nested subsets analysis" or other phenetic synecological or phytosociological methods (Pellens et al., 2005). Giannini and Keller (2007) took issue with this new application on the basis of three misunderstandings. We re-emphasize that communities themselves are analyzed, not landscape parts such as forest fragments. Therefore, it must be clear that communities are analogous to taxa and landscape parts such as fragments are analogous to distributions of taxa. Community evolution is the change in community composition by immigration, emigration and local extinction. Thus, gains and losses of species should not be confused with horizontal transfer. Parsimony analysis does not necessarily group communities based on shared absences of rare species. Rare species are not necessarily absent in the same communities and these absences are not necessarily inferred to be synapomorphies after rooting. This is the main advance expected when cladistics is used instead of the previously cited phenetic methods working with overall similarity.
RESUMO
In forest fragmentation studies, low specific richness in small fragments and community nestedness are usually considered to result from species loss. However, except in the case of fragmentation experiments, these studies cannot distinguish between original low richness and secondary species loss, or between original high richness and secondary colonizations in fragments. To distinguish between these possibilities is a matter of historical inference for which phylogenetic algorithms are designed. The methods of phylogenetic analysis, and especially parsimony analysis, can be used to find a tree of relationships between communities from different forest fragments, taking the presence or absence of species among different communities as characters. Parsimony analysis searches if species subsets can be classified in a nested hierarchy, and also establishes how the communities evolved, polarizing species changes into either extinctions or colonizations. By re-analyzing two classical studies in this new and powerful way, we demonstrate that the differences between fragments and large continuous forests cannot be attributed to species loss in all cases, contrary to expectations from models.