Quintanilha David B, Fernandes Flavio C, Guerra Caroline R, Campos Savio H C, Weber Laura I
Universidade Federal Fluminense (UFF), Instituto de Estudos do Mar Almirante Paulo Moreira (IEAPM), Programa de Pós-Graduação em Biotecnologia Marinha, Arraial do Cabo, RJ, Brazil.
Marinha do Brasil, Instituto de Estudos do Mar Almirante Paulo Moreira (IEAPM), Arraial do Cabo, RJ, Brazil.
Genet Mol Biol. 2022 Apr 29;45(2):e20210247. doi: 10.1590/1678-4685-GMB-2021-0247. eCollection 2022.
Brachidontes exustus (Mollusca, Mytilidae) is mainly distributed in Central America, where it has been recognized as a lataforma species. This study aimed to determine whether B. exustus extends beyond the Amazon Barrier and southward along the Brazilian West Atlantic coast. Mitochondrial genes coding for cytochrome-c oxidase, subunit I (COI) and 16S subunit of ribosomal lataforma cid (16S rRNA) were analyzed with _lata parameters on Brazilian populations (Salvador, Arraial do Cabo and Fernando de Noronha) of scorched mussels previously recorded as B. exustus. Multivariate morphometric _latafor showed partial discrimination of species. Molecular _latafor confirmed B. exustus at Salvador, a population highly similar to Cartagena (Colombia), both belonging to the Atlantic Clade of the B. exustus complex. This fact adds evidence to the idea of the Amazon outflow as a semipermeable barrier. In the southeast of Brazil, B. exustus was not found; instead, B. darwinianus is the species represented at Arraial do Cabo (state of Rio de Janeiro), associated with brackish _lataf. Scorched mussels from Fernando de Noronha are most closely related to B. puniceus from Cape Verde with 4.4% differentiation. Demonstrating an independent evolutionary history since at least the beginning of the Pleistocene, its proposed new name is B. noronhensis.
火烧贻贝（软体动物，贻贝科）主要分布在中美洲，在那里它被认定为一个广布种。本研究旨在确定火烧贻贝是否分布于亚马逊屏障之外，并沿着巴西西大西洋海岸向南延伸。对先前记录为火烧贻贝的巴西种群（萨尔瓦多、卡布弗里奥和费尔南多·迪诺罗尼亚）的编码细胞色素c氧化酶亚基I（COI）和核糖体核糖核酸16S亚基（16S rRNA）的线粒体基因进行了分析，并采用了多种参数。多变量形态测量分析显示了物种的部分区分。分子分析证实了萨尔瓦多的火烧贻贝，该种群与哥伦比亚的卡塔赫纳高度相似，二者均属于火烧贻贝复合体的大西洋分支。这一事实为亚马逊外流作为半透性屏障的观点增添了证据。在巴西东南部未发现火烧贻贝；相反，达尔文贻贝是卡布弗里奥（里约热内卢州）的代表物种，与微咸水有关。费尔南多·迪诺罗尼亚的火烧贻贝与佛得角的紫红贻贝关系最为密切，分化率为4.4%。由于至少从更新世开始就有独立的进化历史，其提议的新名称为诺罗尼亚贻贝。
