Studies have documented biodiversity losses due to intensification of coffee management (reduc-tionPalabras Clave: agroecosistema, biodiversidad, café con sombra, café sin sombra, característico del sitio, meta análisis, producción de café

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The louse genera Brueelia (Ischnocera) and Myrsidea (Amblycera) are broadly codistributed on songbirds (Passeriformes), but differ in a variety of life history characteristics. We used mitochondrial and nuclear DNA sequences to assess levels of genetic divergence and reconstruct phylogenies of these 2 genera, focusing especially on Catharus thrushes in North America. We then qualitatively compared the phylogenies and levels of divergence within these 2 genera of codistributed parasites. Neither Brueelia nor Myrsidea appears to cospeciate with Catharus thrushes or passerine birds in general. The Myrsidea phylogeny exhibits significant levels of biogeographic structure, whereas the Brueelia phylogeny does not. Myrsidea and Brueelia also differ in their levels of intra-generic genetic divergence, with Myrsidea showing higher levels of genetic divergence and host specificity than Brueelia. Our genetic data support traditional morphology-based taxonomy in several instances in which the same species of Brueelia has been reported on multiple host taxa, e.g., all migrant Catharus spp. carry B. antiqua, with little haplotype divergence. Myrsidea found on each Catharus sp. are in general genetically distinct, except for M. incerta, which parasitizes both Catharus ustulatus and Catharus minimus. The strong biogeographic signal in the Myrsidea phylogeny and higher relative levels of host specificity of Myrsidea spp. suggest that infrequent host-switching, followed by speciation, is shaping the evolutionary history of this group. In contrast, the relatively lower host specificity of Brueelia spp. suggests that host-switching, combined with more frequent ongoing dispersal, has been more important in the evolutionary history of Brueelia.

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Biogeographical endemism and habitat restriction are two easily measured quantities that can be used as indicators of species' ecological restrictions. We analysed and compared these two types of information from available literature sources in an attempt to identify all bird species critically dependent on tropical deciduous forests of western Mexico and Central America. Based on patterns of biogeographical restriction, we identified 42 endemics, 33 disjunct endemics, 59 corridor species and 3 seasonal endemics associated with tropical deciduous forest (TDF) in this region. Based on patterns of habitat use in these species, we classified them as 50 tropical deciduous forest-restricted species and 82 apparent habitat generalist species. No habitat use information was available within the TDF belt for five of the biogeographically restricted species. We found a high proportion of apparent habitat generalists (60%) among biogeographically restricted species. We discuss three specific scenarios in which species critically dependent on TDF may nonetheless appear generalized in their patterns of habitat use. These species are termed “cryptic habitat specialists.” The proportion of apparent habitat generalists is highly variable among biogeographical regions and habitat types. Thus, global biodiversity conservation prioritizations that rely on habitat restriction as an indicator of ecological sensitivity may underestimate conservation needs within bioregions that contain high proportions of cryptic habitat specialists.