Unraveling the taxonomy and nomenclature of the Isoetes histrix Bory species complex(Isoetaceae, Lycopodiidae)

Abstract

Based on study of the lectotype of Cephaloceraton gymnocarpum Gennari, megaspore ornamentation, and chromosome number analysis of specimens from different Mediterranean areas, it is shown here that Isoetes gymnocarpa (Gennari) A.Braun is a species endemic to Sardinia, Central Italy, Corsica, and Baleares, different from the Mediterranean I. histrix Bory and from the mainly CE Mediterranean I. sicula Tod. (= I. subinermis (Gennari) Cesca & Peruzzi).