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This study revisits the hypothesis that dispersal to California's Channel Islands follows a stepping-stone pattern from mainland California, based on earlier work indicating that the floras conform to classic island-biogeographic expectations. A re-examination of data incorporating the directions of prevailing and seasonal Santa Ana winds greatly strengthens the power of the model to explain levels of endemism in the Channel Island floras, and suggests the importance of aoelian processes for island colonization. Regression analysis of percent endemism in the native flora against distances measured along the axis of winds improves the r2 from 0.099 to 0.482. The endemic species that flower in the dry season as a percent of the native flora of the islands is also strongly related to these revised source distances ( r2 = 0.665). Furthermore, the native floras of the southern islands are nested subsets of the floras of the northern islands, and angiosperm flowering peaks during the dry season, providing seed for seasonally based dispersal. These results suggest that the northern islands may have served as a source of colonists for the southern islands, and that the pattern of aeolian inputs into an island system should be considered in other plant biogeographic studies. [ABSTRACT FROM AUTHOR]

Isospora sagittulae McQuistion and Capparella, 1992 (Protozoa: Apicomplexa: Eimeriidae) is reported from White-throated Antbirds ( Gymnopithys salvini (Berlepsch, 1901)) and from Common Scale-backed Antbirds ( Willisornis poecilinotus (Cabanis, 1847)), which are thamnophilid birds from the Brazilian Amazon. Its oocysts are ovoidal to ellipsoidal, 28.4 μm × 22.4 μm, with smooth, bilayered wall, 1.1 μm. Micropyle and oocyst residuum are absent, but one to three polar granules are present. Sporocysts are subspherical to ovoidal, 15.0 μm × 12.6 μm. Stieda body thin and flattened and substieda body triangular to round. Sporocyst residuum composed of scattered granules. Sporozoites with refractile body and nucleus. This coccidium was originally described from the Spotted Antbird ( Hylophylax naevioides (Lafresnaye, 1847)), a trans-Andean antbird that is not sympatric with G. salvini and W. poecilinotus, which are cis-Andean antbirds from lowland Amazon forest; therefore, this current study presents some assumptions to explain the dispersion of I. sagittulae among antbird species. [ABSTRACT FROM AUTHOR]

A taxonomic revision of Helichrysum sect. Stoechadina, a section with a Mediterranean distribution, is presented. Taxonomic, nomenclatural, morphological, chromosomal, geographical, and ecological data are provided for each taxon. Eleven taxa are recognized, two lectotypifications are proposed, and a taxonomic key and a sectional description are included. The following new combinations are proposed: Helichrysum italicum subsp. siculum (Jord. & Fourr.) Galbany, L. Sáez & Benedí comb. nov. and Helichrysum italicum subsp. picardii (Boiss. & Reut.) Galbany, L. Sáez & Benedí comb. nov. [ABSTRACT FROM AUTHOR]