Data from: Xianella: a new mat-forming calcified cyanobacterium, Mid–Late Ordovician, North China

Xianella hongii gen. et sp. nov., interpreted to be a calcified cyanobacterial sheath, is described from the Mid–Late Ordovician of Shaanxi, China. Xianella filaments formed cable-like strands that constructed thick fenestral layers. The specimens occur in metre-size limestone blocks, possibly derived from local collapse of a reefal platform margin. In combination with micrite, some of which is intraclastic and peloidal, Xianella created thick and extensive stacks of layered calcified fenestral fabric that appear to be synsedimentarily calcified open-frame mat deposits. The fenestrae range from small, laminose and very irregular, to large equidimensional areas ~2 cm across. Fenestrae with rounded outlines resemble primary gas bubbles observed in present-day microbial mats. These delicate fabrics are comparable in structure and quality of preservation with those of some Proterozoic silicified stromatolitic mats.

洪氏仙氏菌（Xianella hongii gen. et sp. nov.）被鉴定为钙化蓝细菌鞘，其化石产自中国陕西的中晚奥陶世地层。该物种的丝体形成绳状束，构筑出厚实的孔隙层。标本赋存于米级石灰岩块体中，其母岩可能源自礁型台地边缘的局部垮塌。洪氏仙氏菌与部分含内碎屑、球粒的微晶灰岩共生，共同形成了厚层且分布广泛的层状钙化孔隙构造，此类构造属于同沉积钙化的开放式骨架席状沉积物。孔隙形态多样，从小型薄片状、极不规则的形态，到直径约2厘米的大型等轴状区域均有出现。其中轮廓圆润的孔隙与现代微生物席中观测到的原生气泡构造相似。这些精细的构造在结构与保存质量上，可与部分元古宙硅化叠层石席相媲美。