Morales-Ramírez A
Centro de Investigación en Ciencias del Mar y Limnología (CIMAR), Universidad de Costa Rica, San José, Costa Rica.
Rev Biol Trop. 1996 Dec;44 Suppl 3:103-13.
A list of 54 copepod species (Crustacea) in 23 families is presented for the Pacific coast of Costa Rica. Identifications are from zooplankton samples of the Victor Hensen Expedition during December 1993 and February 1994. Samples were taken with a Bongo net (0.60 m net opening, 2.50 m net length) with 200 microns mesh size. Oblique hauls were done from the surface to the ground at a towing speed of aprox. 1 knot. 37 species (68.5%) were found in the Gulf of Nicoya, 36 in Golfo Dulce (66.6%) and 17 (31.4%) species were common to both gulfs, while only twelve species (22.2%) were found in Coronado Bay. Four species (7.4%) were distributed along the coast and were common to the three regions: Paracalanus parvus, Euchaeta sp., Oithona plumifera and O. similis. Eleven species of calanoids found normally in the Costa Rica Dome show the influence of typical oceanic waters principally at the mouth of Gulf of Nicoya. Differences were observed in the composition and presence of the copepod species when the inner and outer (upper and lower) parts of both gulfs were compared. Gulf of Nicoya was dominated in its upper part by typical neritic estuarine species like Acartia lilljenborgii, Paracalanus parvus and, Hemyciclops thalassius as well as species of Pseudodiaptomus. On the other hand a more oceanic composition of copepods was observed in the lower part of the gulf. Both small species, like Oncaea venusta, as well as larger species, such as Pleuromamma robusta, Eucalanus attenuatus, E. elongatus and Rhincalanus nasutus, were typical of these waters. Oithona plumifera and O. similis were found in the lower part too; and both species are typical from oceanic water. Coronado Bay was characterized by the presence of typical oceanic species like Neocalanus gracilis, Euchaeta longicornis, Eucalanus attenuatus and Haloptilus ornatus with more transitional species like Clausocalanus pergens and C. furcatus near the coast. In the Golfo Dulce differences in copepod composition were also observed, but the separation of the species was not so evident. Outer stations were represented by oceanic species like Paracalanus aculeatus, Pleuromamma gracilis, Lucicutia ovalis, Candacia catula, Euchaeta wolfendeni and Oncaea mediterranea, while the inner station, located at the upper part of the Gulf, was more characterized by a mixed copepod group, with both neritic species like Pseudodiaptomus wrigthi, Acartia danae, A. clausi, Canthocalanus pauper as well as oceanic species like Scolicithricella marginata, Saphirina nicromaculata or Oncaea conifera. Two species of Coryceaus, C. flaccus and C. speciosus, were identified in the outer stations of Golfo Dulce, while C. brehmi was found in inner stations of Gulf of Nicoya. The majority of copepods found are typical of the east Pacific. This paper constitutes an additional work about the copepods in the Gulf of Nicoya and the first report of copepod species for Coronado Bay and Golfo Dulce.
本文列出了哥斯达黎加太平洋沿岸的54种桡足类动物（甲壳纲），分属23个科。这些鉴定结果来自1993年12月和1994年2月维克托·亨森考察队的浮游动物样本。样本是用邦戈网（网口0.60米，网长2.50米）采集的，网眼尺寸为200微米。以大约1节的拖曳速度从海面到海底进行倾斜拖网。在尼科亚湾发现了37种（68.5%），在杜尔塞湾发现了36种（66.6%），两个海湾共有17种（31.4%），而在科罗纳多湾仅发现了12种（22.2%）。有4种（7.4%）分布在沿海地区，三个区域都有：小拟哲水蚤、真刺唇角水蚤、 plumifera长腹水蚤和相似长腹水蚤。通常在哥斯达黎加海丘发现的11种哲水蚤类显示出典型大洋水域的影响，主要在尼科亚湾口。比较两个海湾的内湾和外湾（上部和下部）时，观察到桡足类物种的组成和存在情况存在差异。尼科亚湾上部以典型的近岸河口物种为主，如利氏纺锤水蚤、小拟哲水蚤、thalassius半猛水蚤以及伪镖水蚤属的物种。另一方面，在海湾下部观察到桡足类的大洋成分更多。小型物种如venusta真哲水蚤以及大型物种如粗壮胸刺水蚤、attenuatus真刺水蚤、elongatus真刺水蚤和鼻状歪水蚤都是这些水域的典型物种。plumifera长腹水蚤和相似长腹水蚤也出现在下部；这两个物种都是典型的大洋水域物种。科罗纳多湾的特点是存在典型的大洋物种，如新柔哲水蚤、长角真刺唇角水蚤、attenuatus真刺水蚤和ornatus华丽异肢水蚤，以及在海岸附近更多的过渡物种，如pergens克氏纺锤水蚤和furcatus叉状纺锤水蚤。在杜尔塞湾也观察到桡足类组成的差异，但物种的分离不那么明显。外站以大洋物种为主，如尖额拟哲水蚤 gracilis、gracilis优美胸刺水蚤、ovalis椭圆光水蚤、catula卡氏真哲水蚤、wolfendeni沃尔芬登真刺唇角水蚤和mediterranea地中海真哲水蚤，而位于海湾上部的内站则更以混合的桡足类群体为特征，既有近岸物种，如wrighti伪镖水蚤、danae丹氏纺锤水蚤、clausi克氏纺锤水蚤、pauper瘦长纺锤水蚤，也有大洋物种，如marginata缘齿胸刺水蚤、nicromaculata黑斑蓝宝石水蚤或conifera针叶真哲水蚤。在杜尔塞湾的外站鉴定出了两种隆水蚤属物种，flaccus柔弱隆水蚤和speciosus美丽隆水蚤，而在尼科亚湾的内站发现了brehmi布氏隆水蚤。发现的大多数桡足类是东太平洋的典型物种。本文是关于尼科亚湾桡足类的另一项研究，也是科罗纳多湾和杜尔塞湾桡足类物种的首次报告。
