Nummulites with reticulate septal filaments stratigraphically span from the Bartonian to the Rupelian Stages. The size of the proloculus of the megalospheric forms of reticulate species helped recognise N. fabianii – N. fichteli lineage in western Tethys. Unlike the species of this lineage, N. ptukhiani, described from Armenia, is characterised by an unusually large proloculus. A possibly second lineage of reticulate species comprising N. ptukhiani is recently reported from Lutetian – Bartonian succession of Tanzania. The present study examines reticulate species from palaeogeographically adjacent Bartonian succession of Kutch. The statistical analysis of the biometric data suggests the presence of three distinct species, referred to Nummulites ptukhiani, N. aff. hormoensis and N. acutus. The reticulation starts developing in N. acutus that ranges from P13 to P14 in its type locality, Kutch. We infer that Nummulites ptukhiani and N. aff. hormoensis possibly evolved from N. acutus in Zone P14. A binary tree model based on Classification and Regression Tree is proposed to statistically discriminate the three reticulate species.

中文翻译：

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Kutch的巴托尼亚网状Nummulites

具有网状隔丝的 Nummulites 地层从巴托阶到鲁佩阶。网状物种的巨球体前叶的大小有助于识别特提斯西部的 N. fabianii – N. fichteli 谱系。与该谱系的物种不同，来自亚美尼亚的 N. ptukhiani 的特征是异常大的前叶。最近在坦桑尼亚的卢特阶-巴顿系列中报道了可能包含 N. ptukhiani 的第二个网状物种谱系。本研究考察了来自古地理相邻的 Kutch 巴顿系列的网状物种。生物特征数据的统计分析表明存在三个不同的物种，称为 Nummulites ptukhiani, N. aff。hormoensis 和 N. acutus。网状结构在 N 处开始发展。acutus 在其类型区域 Kutch 中的范围从 P13 到 P14。我们推断 Nummulites ptukhiani 和 N. aff。hormoensis 可能从 P14 区的 N. acutus 进化而来。提出了一种基于分类回归树的二叉树模型对三种网状物种进行统计区分。