Department of Biology, Fairmont State College, Fairmont, West Virginia 26554-2470.
Mycologia. 2002 Jan-Feb;94(1):6-20.
An assemblage of myxomycetes associated with inflorescences of large Neotropical herbs, a microhabitat not previously known to support these organisms, is described and characterized ecologically from a number of study sites in Costa Rica, Ecuador, and Puerto Rico. Thirty-one different taxa were found among 652 specimens of myxomycetes recorded in the field or obtained from 358 moist chamber cultures prepared with decaying floral parts. A comparison with the results of 696 moist chamber cultures prepared with various other litter substrates showed that thirteen myxomycete taxa occurred more often on inflorescences. Six taxa had a strong preference for this microhabitat, and three of those seem to be new for the Neotropics. Correspondence analysis of the data set compiled for inflorescences indicated that the assemblage of myxomycetes was relatively consistent across all of the various study sites. The actual myxomycete substrates were the rapidly decaying floral parts enclosed by the massive, still living bracts. Richest in myxomycetes were species of Heliconia and Costus. Here, nectar residuals probably promoted a rapidly developing community of yeasts and bacteria. A high density of these organisms was indicated by the frequent occurrence of myxobacteria in the moist chamber cultures prepared with floral parts. Results from canonical correspondence analysis suggested that a substrate pH between 8 and 9 and the presence of massive, compact inflorescences on plants occurring at lower elevations in localities with moderate annual rainfall provide optimal conditions for inflorescence-inhabiting myxomycetes. An incidental dispersal of myxomycete spores by birds that pollinate the flowers or feed upon the fruits seems possible and may have accounted for the high degree of preference exhibited by some of the inflorescence-inhabiting myxomycetes, for which the term "floricolous" is proposed.
描述了一组与大型新热带草本植物花序相关的黏菌，这是一个以前未知的支持这些生物的微生境，并从哥斯达黎加、厄瓜多尔和波多黎各的多个研究地点对其进行了生态特征描述。在野外记录的 652 个黏菌标本或用 358 个用腐烂的花部分制备的湿室培养物中发现了 31 个不同的分类群。与用各种其他凋落物基质制备的 696 个湿室培养物的结果进行比较表明，有 13 个黏菌类群更常出现在花序上。六个类群强烈偏好这种微生境，其中三个似乎是新热带地区的新种。对为花序编制的数据集中的分析表明，黏菌组合在所有不同的研究地点相对一致。实际的黏菌基质是由大量仍在生长的苞片包围的快速腐烂的花部分。在 Heliconia 和 Costus 等物种中发现的黏菌最丰富。在这里，花蜜残余物可能促进了酵母和细菌的快速发展社区。在用花部分制备的湿室培养物中频繁出现黏细菌表明这些生物的密度很高。典范对应分析的结果表明，植物上位于较低海拔且具有中等年降雨量的地区的基质 pH 值在 8 到 9 之间，并且具有大量密集的花序，为栖息在花序上的黏菌提供了最佳条件。授粉花朵或以果实为食的鸟类可能会偶然传播黏菌孢子，这可能是某些栖息在花序上的黏菌表现出高度偏好的原因，为此提出了“floricolous”一词。
