Okeanos-UAc-Research Institute in Marine Sciences, University of the Azores, Horta, Azores, Portugal.
PeerJ. 2022 Mar 31;10:e13125. doi: 10.7717/peerj.13125. eCollection 2022.
The fried egg jellyfish () is a morphologically peculiar and conspicuous species occurring mostly in the cold waters of the North Pacific. It is less common in the cold waters of the NW Atlantic, and occasionally has been reported in the Mediterranean, Arctic, East and South Pacific, and E, SW and NE Atlantic. However, sightings of this scyphozoan jellyfish have intensified during the past two to three decades in Macaronesia, the Iberian Peninsula and the Mediterranean. These jellyfish are known to be voracious predators of other jellies, but also of other taxa, including fish of commercial interest. Therefore, aggregations may threaten local fisheries, aquaculture, and local biodiversity structuring. We report the first known occurrences of in the Azores Islands, which apparently become more frequent in recent years of the past decade. We confirm, through DNA barcoding of COI and 16S mitochondrial markers, the genetic identity of occurring in the Azores (NE Atlantic). We reveal, with COI sequence data, three (potentially four) cryptic species within the complex. Two species co-occur in the North Pacific. In the North Atlantic (and possibly in the Mediterranean) one or two distinct species exist. Three nominal species of the genus that are currently synonymized, with type localities in the N Pacific, NW Atlantic, and the Mediterranean, need reassessment. The morphotypes previously defined for the four putative species names given for might be eventually differentiated by the number and disposition of the marginal lappets of umbrellae. This morphologic character has to be further inspected in vouchers of the four genetic lineages of , to decide between the description of new species, and the resurrection of junior synonyms through the designation of neotypes with DNA Barcodes, to validate the identity of the cryptic taxa detected. More haplotype sampling is necessary across the distribution of the genus to further investigate the genetic diversity and phylogeographic history of . The high genetic relatedness of from the cold NW Atlantic and the sub-tropical shores of the Azores, revealed by 16S and COI sequence data, suggests a recent invasion, in terms of geologic time, of the temperate waters of the NE Atlantic (and possibly of the Mediterranean). The medusivorous habits of , and especially its predation on the mauve stinger ( spp.) which frequently blooms in Macaronesia and Mediterranean waters, could relate to the recent reports of in the Azores, Madeira, Canary Islands, and the Mediterranean. More investment, including on scientific staff, is necessary to catalog, DNA barcode and monitor jellyfish dynamics more accurately worldwide.
煎蛋水母（ ）是一种形态奇特、引人注目的物种，主要分布在北太平洋的冷水域。它在北大西洋冷水域较少见，偶尔也有报道称在地中海、北极、东太平洋和南太平洋、东大西洋、西南大西洋和东北大西洋出现过。然而，在过去的二三十年里，人们在马卡罗内西亚、伊比利亚半岛和地中海地区观察到这种伞形水母的次数有所增加。已知这些海蜇是其他水母以及其他类群（包括具有商业价值的鱼类）的贪婪捕食者。因此，这些水母的聚集可能会威胁到当地的渔业、水产养殖和当地的生物多样性结构。我们报告了在亚速尔群岛首次发现的 ，近年来这种情况变得更加频繁。我们通过 COI 和 16S 线粒体标记物的 DNA 条形码确认了在亚速尔群岛（北大西洋东北部）出现的 的确切遗传身份。我们利用 COI 序列数据揭示了 复合体中的三个（可能是四个）隐种。在北太平洋，有两个 物种共存。在北大西洋（可能在地中海），存在一个或两个不同的物种。目前被归为同义词的该属的三个指名亚种，其模式产地在北太平洋、北大西洋西北部和地中海，需要重新评估。以前为 四个假定种名定义的形态型，可能最终会通过伞状边缘褶边的数量和位置来区分。在 的四个遗传谱系的凭证样本中，需要进一步检查这种形态特征，以决定是描述新物种，还是通过 DNA 条形码指定新的近缘种来复活低级同义词，以验证所检测到的隐种的身份。需要在该属的分布范围内进行更多的单倍型采样，以进一步研究 的遗传多样性和系统地理历史。16S 和 COI 序列数据显示，来自北大西洋冷水域和亚速尔亚热带海岸的 具有很高的遗传相关性，这表明在地质时间上，它们最近才入侵到北大西洋东北部（可能还有地中海）的温带水域。 的食水母习性，特别是它捕食经常在马卡罗内西亚和地中海水域大量繁殖的紫海刺水母（ ），可能与最近在亚速尔群岛、马德拉群岛、加那利群岛和地中海报道的 有关。全世界需要投入更多的资金，包括科研人员，以更准确地对水母进行编目、DNA 条形码检测和监测。
