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571.
Air drying is not adequate for the preservation of the pansporoblastic membrane of Thelohania maenadis (Protozoa, Microsporidia), a parasite of the crabs Carcinus mediterraneus and Carcinus maenas. Freeze-drying and critical point drying preserve the pansporoblast membrane and reveal that isolated spores of the microsporidian are covered with a thick hairy coat. This coat originates as secretory product within the pansporoblast cavity. 相似文献
572.
ABSTRACT Molt phenology plays an important role in the annual cycles and energetic budgets of migratory birds. The timing and sequence of molt of Nearctic‐Neotropical migratory passerines is generally known for species that undergo a complete prebasic molt on or near the breeding grounds. However, for the few passerine species such as Bobolinks (Dolichonyx oryzivorus) that undergo a complete prealternate molt, the phenology of this molt on the wintering grounds has received little attention. Most studies evaluate prebasic molt, often carried out in conjunction with a different set of competing energetic demands and under dramatically different conditions (e.g., climate and food availability). The prebasic molt of Bobolinks has been described based on limited museum collections, but the sequence and phenology of the prealternate molt have not been examined. We collected molt data from 242 Bobolinks captured from January to March in Bolivia (2005–2007) and Argentina (2008). We quantified prealternate molt sequence and used a maximum likelihood approach to estimate molt initiation date and duration. We used AIC model selection to evaluate the potential effects of region, year, and sex on prealternate molt phenology. Onset and duration of molt did not differ among years or between males and females. Estimated molt duration was 13 d longer at Bolivia sites than at sites 1200 km further southeast in Argentina, but molt duration in Argentina varied and the difference was not statistically significant. Molt sequence was consistent among populations, and showed only slight deviations from what has been previously reported for Bobolinks. Our results suggest that regional wintering populations of Bobolinks do not mix in a given year, and local factors such as climate and food availability may influence molt phenology. 相似文献