Department of Biology, John Carroll University, University Heights, Ohio, USA.
School of Life Sciences, University of Nevada-Las Vegas, Las Vegas, Nevada, USA.
J Phycol. 2023 Dec;59(6):1217-1236. doi: 10.1111/jpy.13389. Epub 2023 Sep 11.
Knowledge of the tropical terrestrial cyanobacterial flora from the African continent is still limited. Of 31 strains isolated from soil and subaerial samples collected in Lagos State, Nigeria, three were found to be in the Oculatellaceae, including two species in a new genus. Subsequently, isolates from microbial mats in White Sands National Park in New Mexico, United States, and from a rock near the ocean in Puerto Rico, United States, were found to belong to the new genus as well. Cyanobacterial isolates were characterized microscopically, sequenced for the 16S rRNA gene and associated ITS region, and phylogenetically analyzed. Egbenema gen. nov., with three new species, as well as two new species of Albertania were differentiated from all other Oculatellaceae. Both genera belong to a supported clade within the Oculatellaceae that includes Trichotorquatus and Komarkovaea. The two new species of Albertania, A. egbensis and A. latericola, were from the same sample, but were evolutionarily separate based on 16S rRNA gene phylogenies, percent identity below the 98.7% threshold, and ITS rRNA percent dissimilarity >7.0%. Egbenema aeruginosum gen. et sp. nov. was phylogenetically separated from Trichotorquatus and Albertania but was in a clade with other strains belonging to Egbenema. The two Egbenema strains from the United States are here named Egbenema epilithicum sp. nov. and Egbenema gypsiphilum sp. nov. Our results support the hypothesis that further species discoveries of novel cyanobacteria will likely be made in soils and subaerial habitats, as these habitats continue to be studied, both in tropical and temperate biomes.
非洲热带陆生蓝藻的知识仍然有限。从尼日利亚拉各斯州采集的土壤和亚气生样本中分离出的 31 株菌株中,有 3 株属于 Oculatellaceae,其中包括 2 个新属的种。随后,从美国新墨西哥州白沙国家公园的微生物垫和美国波多黎各海洋附近的岩石中分离出的菌株也属于新属。对蓝藻分离物进行了显微镜观察、16S rRNA 基因和相关 ITS 区的测序,并进行了系统发育分析。Egbenema 属,有 3 个新种,以及 Albertania 的两个新种,与所有其他 Oculatellaceae 物种都不同。这两个属都属于 Oculatellaceae 中的一个支持分支,包括 Trichotorquatus 和 Komarkovaea。Albertania 的两个新种,A. egbensis 和 A. latericola,来自同一个样本,但基于 16S rRNA 基因系统发育树、低于 98.7%阈值的同一性百分比和 ITS rRNA 差异百分比>7.0%,它们在进化上是独立的。Egbenema aeruginosum gen. et sp. nov. 在系统发育上与 Trichotorquatus 和 Albertania 分离,但与其他属于 Egbenema 的菌株在一个分支中。美国的两种 Egbenema 菌株分别命名为 Egbenema epilithicum sp. nov. 和 Egbenema gypsiphilum sp. nov. 我们的研究结果支持这样一种假设,即随着这些生境继续被研究,在热带和温带生物群系中,很可能会在土壤和亚气生生境中发现更多新的蓝藻物种。