A 1901 report by the Smithsonian Custodian of Paleozoic Plants noted that the nonbiomineralized taxa Buthotrephis divaricata White, 1901, B. newlini White, 1901, and B. lesquereuxi Grote and Pitt, 1876, from the upper Silurian of the Great Lakes area, shared key characteristics in common with the extant green macroalga Codium. A detailed reexamination of these Codium-like taxa and similar forms from the lower Silurian of Ontario, New York, and Michigan, including newly collected material of Thalassocystis striata Taggart and Parker, 1976, aided by scanning electron microscopy and stable carbon isotope analysis, provides new data in support of an algal affinity. Crucially, as with Codium, the originally cylindrical axes of all of these taxa consist of a complex internal array of tubes divided into distinct medullary and cortical regions, the medullary tubes being arranged in a manner similar to those of living Pseudocodium. In view of these findings, the three study taxa originally assigned to Buthotrephis, together with Chondrites verus Ruedemann, 1925, are transferred to the new algal taxon Inocladus new genus, thereby establishing Inocladus lesquereuxi new combination, Inocladus newlini new comb., Inocladus divaricata new comb., and Inocladus verus new comb. Morphological and paleoecological data point to a phylogenetic affinity for Inocladus n. gen. and Thalassocystis within the Codium-bearing green algal order Bryopsidales, but perhaps nested within an extinct lineage. Collectively, this material fits within a large-scale pattern of major macroalgal morphological diversification initiated in concert with the Great Ordovician Biodiversification Event and apparently driven by a marked escalation in grazing pressure.UUID: http://zoobank.org/97c5c737-b291-41a2-aceb-f398cac9537a

中文翻译：

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来自北美志留纪的类钠类群：形态学、分类学、古生态学和系统发育亲和性

史密森尼古生代植物监护人 1901 年的一份报告指出，非生物矿化类群牛头菇怀特，1901 年，B. newlini怀特，1901 年和B. lesquereuxiGrote 和 Pitt，1876 年，来自五大湖地区的上志留纪，与现存的绿色大型藻类具有共同的关键特征钠. 详细复查这些钠- 来自安大略、纽约和密歇根下志留纪的类群和类似形式，包括新收集的海藻Taggart 和 Parker，1976 年，在扫描电子显微镜和稳定碳同位素分析的帮助下，提供了支持藻类亲和力的新数据。至关重要的是，与钠，所有这些分类群的原始圆柱轴由复杂的内部管阵列组成，分为不同的髓质和皮质区域，髓质管的排列方式类似于活体伪钠. 鉴于这些发现，最初分配给鲶鱼， 和...一起球粒陨石Ruedemann，1925，被转移到新的藻类分类单元月桂树新属，从而确立斑鸠菊新组合，新线虫新梳子，黄花菜新梳子，和猪笼草新梳子。形态学和古生态学数据表明，月桂树n. 将军 和海藻内钠- 带有绿藻目 Bryopsidales，但可能嵌套在已灭绝的谱系中。总的来说，这种材料符合与大奥陶纪生物多样性事件一起发起的大型大型藻类形态多样化模式，并且显然是由放牧压力的显着升级驱动的。UUID：http://zoobank.org/97c5c737-b291-41a2-aceb-f398cac9537a