Barger Michael A
Department of Natural Science, Peru State College, Peru, Nebraska 68421, USA.
J Parasitol. 2006 Apr;92(2):230-5. doi: 10.1645/GE-645R1.1.
The intestinal helminth communities of creek chub (Semotilus atromaculatus) were studied in the streams of southeastern Nebraska to characterize spatial variation, to determine whether drainages act as regional species pools, and to examine the spatial patterning of individual parasite species within and among drainages. Creek chub were sampled in the summer of 2003 and the spring of 2004 at each of 12 sites distributed evenly among 3 drainages in the Big Nemaha River watershed. Four intestinal helminths were recovered: Allocreadium lobatum, Proteocephalus sp., Rhabdochona canadensis, and Paulisentis missouriensis. Host size had little or no effect on the composition of the parasite communities of creek chub, either among individual fish or among samples. In contrast, drainage and sample date explained 82% of the variation in mean infracommunity species richness among samples, and 62% of the variation in mean infracommunity abundance among samples. Drainage differences were determined by the distributions of P. missouriensis and R. canadensis; whereas, A. lobatum and Proteocephalus sp. were more uniformly distributed among drainages. Each drainage was characterized by a unique pattern of species diversity at infracommunity, component community, and drainage levels of organization.
为了描述空间变异特征、确定流域是否作为区域物种库以及研究各流域内和流域间单个寄生虫物种的空间格局，对内布拉斯加州东南部溪流中的溪鲈（Semotilus atromaculatus）肠道蠕虫群落进行了研究。2003年夏季和2004年春季，在大尼马哈河流域3个流域中均匀分布的12个地点采集了溪鲈样本。共发现4种肠道蠕虫：叶状异肉吸虫（Allocreadium lobatum）、Proteocephalus属线虫、加拿大斜睾吸虫（Rhabdochona canadensis）和密苏里泡吻棘头虫（Paulisentis missouriensis）。宿主大小对溪鲈寄生虫群落的组成几乎没有影响，无论是在个体鱼之间还是样本之间。相比之下，流域和采样日期解释了样本间平均群落内物种丰富度变异的82%，以及样本间平均群落内丰度变异的62%。流域差异由密苏里泡吻棘头虫和加拿大斜睾吸虫的分布决定；而叶状异肉吸虫和Proteocephalus属线虫在各流域的分布更为均匀。每个流域在群落内、组成群落和流域组织水平上都具有独特的物种多样性模式。
