Adlafia kociolekii sp. nov. (Bacillariophyceae): a new naviculoid diatom from the Eastern Himalayas, India

We describe Adlafia kociolekii sp. nov. from aerial habitats in Sikkim, India, a part of the Eastern Himalayas. The species is described based on light and scanning electron microscopic observations. The main diagnostic features include valves are clear elliptical, a narrow axial area at the centre, radiate to convergent striation, and distinctive Voigt discontinuity at both apices. In terms of ultrastructure, the features that identify this species as new are the internally presence of raphe on the elevated sternum, with distal raphe ends distinctly deflected to opposite sides of proximal ends, and distal ends terminating in long and thickened helictoglossae. The species was also recorded from wet walls and freshwater habitats of north-east India, in the present study. The morphological features of the species are compared with other closely similar taxa ofAdalfia and other naviculoid genera.

Automated summary

We describe a new species of Adlafia called Adlafia kociolekii from aerial habitats in Sikkim, India. The species was observed and described based on light and scanning electron microscopy observations. The main diagnostic features of this species include clear elliptical valves, a narrow axial area at the centre, radiate to convergent striation, and a distinctive Voigt discontinuity at both apices. The ultrastructure of this species, including the presence of a raphe on the elevated sternum, distal raphe ends deflected to opposite sides of proximal ends, and distal ends terminating in long and thickened helictoglossae, distinguishes it as a new species. The species was also found in wet walls and freshwater habitats in northeast India. Morphological features of this species were compared with closely similar taxa of Adlafia and other naviculoid genera.