Planctomycetes occur in almost all aquatic ecosystems on earth. They have a remarkable cell biology, and members of the orders Planctomycetales and Pirellulales feature cell division by polar budding, perform a lifestyle switch from sessile to motile cells and have an enlarged periplasmic space. Here, we characterise a novel planctomycetal strain, Pla110^T, isolated from the surface of polystyrene particles incubated in the Baltic Sea. After phylogenetic analysis, the strain could be placed in the family Planctomycetaceae. Strain Pla110^T performs cell division by budding, has crateriform structures and grows in aggregates or rosettes. The strain is a chemoheterotroph, grows under mesophilic and neutrophilic conditions, and exhibited a doubling time of 21 h. Based on our phylogenetic and morphological characterisation, strain Pla110^T (DSM 103387^T = LMG 29693^T) is concluded to represent a novel species belonging to a novel genus, for which we propose the name Polystyrenella longa gen. nov., sp. nov.

浮游菌存在于地球上几乎所有的水生生态系统中。他们有一个显着的细胞生物学和订单的成员Planctomycetales和Pirellulales由极性萌芽功能细胞分裂，从固着进行一种生活方式切换到运动细胞，并有扩大的周质空间。在这里，我们表征了一种新的浮游菌菌株 Pla110 ^T，它是从波罗的海中孵化的聚苯乙烯颗粒表面分离出来的。经系统发育分析，该菌株可归入浮游菌科。应变 Pla110 ^T通过出芽进行细胞分裂，具有环形结构并以聚集体或玫瑰花结生长。该菌株是一种化学异养菌，在嗜中性和嗜中性条件下生长，倍增时间为 21 小时。基于我们的系统发育和形态学特征，菌株 Pla110 ^T (DSM 103387 ^T  = LMG 29693 ^T ) 被推断为代表一个新属的新物种，我们建议将其命名为聚苯乙烯。十一月，sp。十一月