The Appearance of Ulva laetevirens(Ulvophyceae, Chlorophyta) in the Northeast Coast of the United States of America  

作　　者：MAO Yunxiang Jang Kyun Kim Roderick Wilson Charles Yarish 

机构地区：[1]Department of Ecology and Evolutionary Biology, University of Connecticut at Stamford [2]Key Laboratory of Marine Genetics and Breeding (MOE), College of Marine Life Sciences, Ocean University of China [3]Department of Marine Sciences, University of Connecticut at Stamford

出　　处：《Journal of Ocean University of China》2014年第5期865-870,共6页中国海洋大学学报（英文版）

基　　金：partly funded by the China Scholarship Council;supports of this work by the Connecticut Sea Grant College Program (NA10OAR4170095; CT Sea Grant R/A38);from the Perkin Elmer research fund at the University of Connecticut, Perkin Elmer Analytical Division of E, G & G, Wellesley, MA, USA

摘　　要：Introduced species may outcompete or hybridize with native species, resulting in the loss of native biodiversity or even alteration of ecosystem processes. In this study, we reported an alien distromatic Ulva species, which was found in an embayment(Holly Pond) connected with Long Island Sound, USA. The morphological and anatomical observations in combination with molecular data were used for its identification to species. Anatomy of collected specimens showed that the cell shape in rhizoidal and basal regions was round and the marginal teeth along the basal and median region were not found. These characteristics were primarily identical to the diagnostic characteristics of Ulva laetevirens Areschoug(Chlorophyta). The plastid-encoding tufA and nucleus-encoding ITS1 were used for its molecular identification. Phylogenetic analysis for the tufA gene placed the specimens from Holly Pond in a well-supported clade along with published sequences of U. laetevirens identified early without any sequence divergence. In ITS tree, the sample also formed well-supported clades with the sequences of U. laetevirens with an estimated sequence divergence among the taxa in these clades as low as 1%. These findings confirmed the morpho-anatomical conclusion. Native to Australia, this species was reported in several countries along the Mediterranean coast after the late of 1990 s. This is the first time that U. laetevirens is found in the northeast coast of United States and the second record for Atlantic North America.Introduced species may outcompete or hybridize with native species, resulting in the loss of native biodiversity or even alteration of ecosystem processes. In this study, we reported an alien distromatic Ulva species, which was found in an embayment（Holly Pond） connected with Long Island Sound, USA. The morphological and anatomical observations in combination with molecular data were used for its identification to species. Anatomy of collected specimens showed that the cell shape in rhizoidal and basal regions was round and the marginal teeth along the basal and median region were not found. These characteristics were primarily identical to the diagnostic characteristics of Ulva laetevirens Areschoug（Chlorophyta）. The plastid-encoding tufA and nucleus-encoding ITS1 were used for its molecular identification. Phylogenetic analysis for the tufA gene placed the specimens from Holly Pond in a well-supported clade along with published sequences of U. laetevirens identified early without any sequence divergence. In ITS tree, the sample also formed well-supported clades with the sequences of U. laetevirens with an estimated sequence divergence among the taxa in these clades as low as 1%. These findings confirmed the morpho-anatomical conclusion. Native to Australia, this species was reported in several countries along the Mediterranean coast after the late of 1990 s. This is the first time that U. laetevirens is found in the northeast coast of United States and the second record for Atlantic North America.

关 键 词：Ulva laetevirens Areschoug introduced seaweed Long Island Sound USA ITS TUFA 

分 类 号：Q949.2[生物学—植物学]