Geographical range and taxonomic divergence in North Atlantic Calanus (C. helgolandicus, C. finmarchicus and C. glacialis)
Geographical range and taxonomic divergence in North Atlantic Calanus (C. helgolandicus, C. finmarchicus and C. glacialis)
复制标题
北大西洋 Calanus（C. helgolandicus、C. finmarchicus 和 C. glacialis）的地理范围和分类差异
DOI：
--
复制
发表时间：
1977
期刊：
影响因子：
--
通讯作者：
K. Hulsemann
中科院分区：
文献类型：
--
作者：
A. Fleminger;K. Hulsemann
已知的分布在北大西洋漂流的哲水蚤helgolandicus是很难解释在没有一个繁殖活跃的人口居住在大陆沃茨关闭北美东部。新的证据表明，过去被忽视的这一人口实际上确实存在。该物种是在一项对海洋资源监测、评估和预测计划（MARMAP）的浮游动物样本的研究中发现的，该计划调查了哈特拉斯角和纽约湾之间的鱼类浮游生物。性活动在这些股票的C。根据卵巢的成熟度、雄性出现的频率、雌性贮精器中精子的存在以及携带哲水蚤精荚的雌性的外观，可以表明Helgolandicus。新的记录提供了一个可能的起源，该物种的存在，在拉布拉多大银行附近，以及进一步向东在北大西洋漂移。C. finmarchicus与C. helgolandicus在MARMAP收集，这是从一个地区毗邻的最南端，已知的分布，C。冰川皮肤器官的分布（即，孔特征模式）以确定它们是否在分类学上有用。在雌性的尿小体上发现了显著不同的模式。极性物种C之间的孔特征差异。glacialis和温带C. helgolandicus被证明是明显的北方C. Finmarchicus和它的两个邻近物种。连续重叠的范围和孔签名模式的显着差异表明，从一般模式的表皮器官分布的分歧一直是对三个物种之间的杂交选择的产物。如果这是真的，那么C. helgolandicus与C. finmarchicus和C.在这三个物种的历史上，冰河时期是相当可观的。
The known distribution of Calanus helgolandicus in the North Atlantic Drift is difficult to explain in the absence of a reproductively active population inhabiting continental waters off eastern North America. New evidece indicates that this population, overlooked in the past, does in fact exist. The species has been found in a study of zooplankton samples from a number of MARMAP (Marine Resource Monitoring, Assessment, and Prediction Program) cruises surveying ichthyoplankton between Cape Hatteras and the New York Bight. Sexual activity in these stocks of C. helgolandicus was indicated by the ripeness of ovaries, the frequency of males, the presence of sperm in the females' seminal receptacles and the appearance of a female bearing a Calanus spermatophore. The new records provide a likely origin for the presence of the species in the vicinity of the Labrador Grand Banks as well as further east in the North Atlantic Drift. C. finmarchicus, similarly sexually active, was found to be sympatric with C. helgolandicus in the MARMAP collections which were taken from a region contiguous with the southernmost, known distribution, of C. glacialis. The distribution of integumental organs (i.e., pore signature patterns) was examined in the three species to determine whether they would be taxonomically useful. Strikingly different patterns were found on the female urosome. Pore signature differences between the polar species C. glacialis and the temperate C. helgolandicus proved to be as pronounced as those between the boreal C. finmarchicus and its two neighboring species. The successively overlapping ranges and the distinctive differences in pore signature patterns suggest that divergence from the generic pattern of integumental organ distribution has been a product of selection against hybridizing among the three species. If this is in fact the case, the reproductive range of C. helgolandicus has overlapped with those of C. finmarchicus and C. glacialis for appreciable periods in the history of the three species.