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Nummuliteswith 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 recogniseN. fabianii–N. fichtelilineage 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 comprisingN. ptukhianiis 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 toNummulites ptukhiani,N.aff.hormoensisandN. acutus. The reticulation starts developing inN. acutusthat ranges from P13 to P14 in its type locality, Kutch. We infer thatNummulites ptukhianiandN.aff.hormoensispossibly evolved fromN. acutusin Zone P14. A binary tree model based on Classification and Regression Tree is proposed to statistically discriminate the three reticulate species. [ABSTRACT FROM AUTHOR]