Esch G W, Curtis L A, Barger M A
Department of Biology, Wake Forest University, Winston-Salem, NC 27109, USA.
Parasitology. 2001;123 Suppl:S57-75. doi: 10.1017/s0031182001007697.
This paper presents a perspective on the ecology of trematodes in snail hosts based on recent evidence. Because flukes use snails almost obligatorily as first intermediate hosts, we highlight the role of gastropods as keystone species for trematodes and their communities. After reviewing recent developments in the transmission of trematodes to and from snails, we discuss trematode communities within individual snails (infracommunities) and in snail populations (component communities). Results garnered using various protocols at the infracommunity level are reviewed. The few data available, all from marine systems, indicate that low colonization rates characterize infracommunities, suggesting that trematode infracommunities tend to be isolationist in character rather than interactive. The variety of trematode species present in a component community seems to be determined by spatial overlap of definitive hosts. Relative abundance of species in a component community shows little dependence on negative interspecific interactions at the level of the infracommunity. Temporal aspects of trematode communities are related to the life history of the host snail. The component communities of long-lived snails (mostly marine) integrate many infection episodes whereas shorter-lived snails (mostly freshwater) acquire new component communities each time host cohorts turnover.
本文基于近期证据，阐述了吸虫在螺类宿主中的生态学观点。由于吸虫几乎必然以螺类作为第一中间宿主，我们强调腹足纲动物作为吸虫及其群落关键物种的作用。在回顾吸虫与螺类之间传播的最新进展后，我们讨论了单个螺类体内的吸虫群落（内群落）以及螺类种群中的吸虫群落（组群落）。本文回顾了在群落水平上使用各种方法获得的结果。现有的少量数据均来自海洋系统，这些数据表明内群落的定殖率较低，这表明吸虫内群落往往具有孤立性而非交互性。组群落中存在的吸虫种类似乎由终末宿主的空间重叠决定。组群落中物种的相对丰度几乎不依赖于内群落水平上的种间负相互作用。吸虫群落的时间动态与宿主螺类的生活史相关。长寿螺类（大多为海洋螺类）的组群落整合了多次感染事件，而寿命较短的螺类（大多为淡水螺类）每次宿主群体更新时都会获得新的组群落。
