Laboratório de Microalgas Marinhas, Universidade Federal do Estado do Rio de Janeiro - UNIRIO, Av. Pasteur, 458, Urca, Rio de Janeiro, 22290-240, RJ, Brazil.
Laboratório de Biodiversidade e Evolução Molecular, Universidade Federal do Estado do Rio de Janeiro - UNIRIO, Av. Pasteur, 458, Urca, Rio de Janeiro, 22290-240, RJ, Brazil.
Harmful Algae. 2023 Aug;127:102470. doi: 10.1016/j.hal.2023.102470. Epub 2023 Jun 10.
In the tropical and subtropical South Atlantic Ocean, studies on the taxonomy and abundance of benthic harmful algae are scarce and the region has been largely under investigated. In this study, morphological descriptions, molecular (LSU rDNA and ITS region) and abundance data of benthic Prorocentrum species from the tropical and subtropical Southwest Atlantic and three oceanic islands are presented. Moreover, a review of global benthic Prorocentrum species richness and distribution is presented. Eleven benthic Prorocentrum species were found in Brazil. Morphological and molecular data on P. borbonicum, P. hoffmannianum, P. lima species complex and P. rhathymum were provided. Prorocentrum panamense, P. cf. caipirignum, P. cf. concavum, P. cf. norrisianum, P. emarginatum/fukuyoi/sculptile complex and two not identified species were observed using scanning electron and/or light microscopy, and morphological descriptions are presented. Prorocentrum lima species complex was found at all investigated sites, in abundances up to 2 × 10 cells g FW at the Northeast Brazil, while maximum abundance of all the remaining species did not exceed 1 × 10 cells g FW. The Fernando de Noronha archipelago can be considered a hotspot of benthic Prorocentrum species diversity, with ten species registered. Data compiled in the literature review shows a clear latitudinal gradient with higher species richness in tropical and subtropical regions relative to temperate areas. It is also evident that there is a bias caused by taxonomic impediment and an uneven sampling effort, with many regions still to be investigated using a combined morphological and molecular effort. Therefore, the current knowledge on the global distribution of benthic Prorocentrum species is likely underestimated.
在热带和亚热带南大西洋，有关底栖有害藻类分类学和丰度的研究很少，该地区的调查研究也很少。本研究提供了来自热带和亚热带西南大西洋和三个大洋岛屿的底栖原甲藻属物种的形态描述、分子（LSU rDNA 和 ITS 区）和丰度数据。此外，还对全球底栖原甲藻属物种丰富度和分布进行了综述。在巴西发现了 11 种底栖原甲藻。提供了关于 P. borbonicum、P. hoffmannianum、P. lima 种复合体和 P. rhathymum 的形态学和分子数据。使用扫描电子显微镜和/或光学显微镜观察到了 Prorocentrum panamense、P. cf. caipirignum、P. cf. concavum、P. cf. norrisianum、P. emarginatum/fukuyoi/sculptile 复合体和两个未鉴定的物种，并提供了形态描述。在所有调查地点都发现了 P. lima 种复合体，在巴西东北部的丰度高达 2×10 个细胞 g FW，而所有其余物种的最大丰度都不超过 1×10 个细胞 g FW。费尔南多-迪诺罗尼亚群岛可以被认为是底栖原甲藻属物种多样性的热点地区，有 10 个物种被记录。文献综述中汇编的数据显示出明显的纬度梯度，热带和亚热带地区的物种丰富度高于温带地区。很明显，由于分类障碍和采样努力不平衡，存在偏差，许多地区仍需要通过形态学和分子学相结合的方法进行调查。因此，目前对全球底栖原甲藻属物种分布的了解很可能被低估了。
