DNA Barcoding of Moon Jellyfish (Cnidaria, Scyphozoa, Ulmaridae, Aurelia): Two Cryptic Species from the Azores (NE Atlantic, Macaronesia), and Evaluation of the Non-Indigenous Species (NIS)

Abstract

Moon jellies are some of the most popular, widely distributed, and best-studied marine jellyfish. By the end of the past century only two or three Aurelia species were recognized, but with the rise of DNA barcoding studies, around thirty Aurelia species are presently accepted. Most of the species are morphologically indistinguishable and have restricted biogeography. We reveal, with COI, 16S, and ITS1-5.8S sequence data, two (pseudo-)cryptic species of Aurelia, potentially endemic to the Azores ecoregion, herein provisionally classified as A. “cf. pseudosolida” and A. “misteriosa”. These species are closely related to the Mediterranean lineages of A. pseudosolida and A. persea, respectively. In the Azores, the shape of the campanula and oral arms readily distinguishes the two species: the former with folded oral arms and globose campanula, and the latter with flattened campanula and thick and long oral arms. Previous reports of A. solida and A. aurita in the Azores should generally correspond to A. “misteriosa” and A. cf. pseudosolida, respectively. The phylogenetic (re-)examination of the available DNA barcodes of Aurelia only evidenced human-mediated dispersal for A. coerulea, A. relicta, and A. aurita. Aurelia solida cannot be yet considered NIS in the Mediterranean. More jellyfish DNA (meta)barcoding should reveal further cryptic diversity, biological invasions, and phylogeographic inferences.

Angiopteris nodosipetiolata (Marattiaceae), a new fern species from Yunnan, China

“…Notable groups that include cryptic species encompass organisms like Isoetes Linnaeus (1753 : 1100; Gu et al (2022) ), Ceratopteris Brongn. (1822: 186; Yu et al (2021) ) and jellyfish ( Moura et al 2023 ). Angiopteris nodosipetiolata shares a remarkable morphological resemblance with A.…”

Reconstructing the Biogeographic History of the Genus Aurelia Lamarck, 1816 (Cnidaria, Scyphozoa), and Reassessing the Nonindigenous Status of A. solida and A. coerulea in the Mediterranean Sea

“…Given the recent resurrection and new species description within the genus Aurelia [1,[11][12][13][14] and the absence of taxonomic diagnosis characters [1], the biogeography of the species should be restricted to the locations where genetic determinations were made. In this section, we implemented a modified version of the PRISMA method [33] to systematically review the locations with available genetic data on Aurelia.…”

“…First, current accepted species [44] and the not-yet-described sensu Lawley et al [1] and sensu Moura et al [14] were individually searched on the nucleotide databases GenBank and Barcode of Life Data System (BOLD, https://boldsystems.org/, accessed on 20 July 2023). For each sequence, we retrieved specimen collection coordinates.…”

“…A. aurita was excluded from this step given the high number of nonreviewed sequences deposited before the determination of the cryptic nature of the species. Next, we extracted the coordinates from the sequences obtained on global-scale genetic analyses of the genus Aurelia [1,14] and removed the duplicates.…”

“…However, the genetic variability found in the phylogenetic analysis carried out by Dawson and Martin [9] indicated that A. aurita is part of a taxonomic complex including various species. Identifying different species based on diagnostic characters is challenging [1,10,11], but the combination of taxonomic and phylogenetic analyses has increased the number of species up to 30 in 2023 through name resurrections and new descriptions [1,[11][12][13][14].…”