{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T18:59:56Z","timestamp":1778698796081,"version":"3.51.4"},"reference-count":45,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2024,10,21]],"date-time":"2024-10-21T00:00:00Z","timestamp":1729468800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Portuguese Foundation for Science and Technology (FCT)","award":["UIDB\/04423\/2020"],"award-info":[{"award-number":["UIDB\/04423\/2020"]}]},{"name":"the Portuguese Foundation for Science and Technology (FCT)","award":["UIDP\/04423\/2020"],"award-info":[{"award-number":["UIDP\/04423\/2020"]}]},{"name":"the Portuguese Foundation for Science and Technology (FCT)","award":["C644915664-00000026"],"award-info":[{"award-number":["C644915664-00000026"]}]},{"name":"the WP9\u2014Portuguese Blue Biobank under the Blue Economy Pact","award":["UIDB\/04423\/2020"],"award-info":[{"award-number":["UIDB\/04423\/2020"]}]},{"name":"the WP9\u2014Portuguese Blue Biobank under the Blue Economy Pact","award":["UIDP\/04423\/2020"],"award-info":[{"award-number":["UIDP\/04423\/2020"]}]},{"name":"the WP9\u2014Portuguese Blue Biobank under the Blue Economy Pact","award":["C644915664-00000026"],"award-info":[{"award-number":["C644915664-00000026"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>In this paper, we examine the filamentous cyanobacterial strain NILCB16 and describe it as a new species within the genus Pegethrix. The original population was sampled from a mat growing in an irrigation canal in the Nile River, Egypt. Initially classified under Plectonema or Planktolyngbya, the strain is a potential producer of the toxins microcystin and \u03b2-N-Methylamino-L-Alanine (BMAA). Additionally, we reviewed the taxonomic relationships between the Oculatellales genera. To describe the new species, we conducted a polyphasic study, encompassing 16S rRNA gene phylogenetic analyses performed using both Maximum Likelihood and Bayesian methods, sequence identity (p-distance) analysis, 16S-23S ITS secondary structures, and morphological and habitat comparisons. The phylogenetic analysis revealed that strain NILCB16 clustered within the Pegethrix clade with strong phylogenetic support, but in a distinct position from other species in the genus. The strain shared a maximum 16S rRNA gene identity of 97.3% with P. qiandaoensis and 96.1% with the type species, P. bostrychoides. Morphologically, NILCB16 can be differentiated from other species in the genus by its lack of false branching. Our phylogenetic analyses also show that Pegethrix, Cartusia, Elainella, and Maricoleus are clustered with strong phylogenetic support. They exhibit high 16S rRNA gene identity and are morphologically indistinguishable, suggesting they could potentially be merged into a single genus in the future.<\/jats:p>","DOI":"10.3390\/toxins16100451","type":"journal-article","created":{"date-parts":[[2024,10,21]],"date-time":"2024-10-21T10:49:22Z","timestamp":1729507762000},"page":"451","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Description of Pegethrix niliensis sp. nov., a Novel Cyanobacterium from the Nile River Basin, Egypt: A Polyphasic Analysis and Comparative Study of Related Genera in the Oculatellales Order"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4396-024X","authenticated-orcid":false,"given":"Guilherme Scotta","family":"Hentschke","sequence":"first","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros de Leix\u00f5es, Av. General Norton de Matos s\/n, 4450-208 Matosinhos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6378-1914","authenticated-orcid":false,"given":"Zakaria","family":"Mohamed","sequence":"additional","affiliation":[{"name":"Department of Botany and Microbiology, Faculty of Science, Sohag University, Sohag 82524, Egypt"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4621-885X","authenticated-orcid":false,"given":"Alexandre","family":"Campos","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros de Leix\u00f5es, Av. General Norton de Matos s\/n, 4450-208 Matosinhos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3585-2417","authenticated-orcid":false,"given":"Vitor M.","family":"Vasconcelos","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros de Leix\u00f5es, Av. General Norton de Matos s\/n, 4450-208 Matosinhos, Portugal"},{"name":"Faculty of Sciences, University of Porto, Rua do Campo Alegre s\/n, 4069-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"769","DOI":"10.1111\/pala.12178","article-title":"Cyanobacteria and the Great Oxidation Event: Evidence from Genes and Fossils","volume":"58","author":"Schirrmeister","year":"2015","journal-title":"Paleontology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1016\/j.toxicon.2007.07.007","article-title":"Toxic Cyanobacteria and Cyanotoxins in Public Hot Springs in Saudi Arabia","volume":"51","author":"Mohamed","year":"2008","journal-title":"Toxicon"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/j.ympev.2016.08.010","article-title":"Detection of the New Cosmopolitan Genus Thermoleptolyngbya (Cyanobacteria, Leptolyngbyaceae) Using the 16S RRNA Gene and 16S\u201323S ITS Region","volume":"105","author":"Sciuto","year":"2016","journal-title":"Mol. 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