Stauroneis dharwarensis Wadmare & B.Karthick, 2022

Wadmare, Neha & Karthick, Balasubramanian, 2022, Revisiting two Stauroneis Ehrenberg (Bacillariophyta) from H. P. Gandhi’s Diatom collection: Notes on Ultrastructure, Types and Nomenclature, Phytotaxa 555 (1), pp. 42-52 : 47-48

publication ID	https://doi.org/ 10.11646/phytotaxa.555.1.3
DOI	https://doi.org/10.5281/zenodo.6886191
persistent identifier	https://treatment.plazi.org/id/E93BC556-FFF3-DA6C-1DDB-C38DE1EA7AE0
treatment provided by	Plazi
scientific name	Stauroneis dharwarensis Wadmare & B.Karthick
status	nom. nov., stat. nov.

Treatment

Stauroneis dharwarensis Wadmare & B.Karthick nom. nov., stat. nov. ( Figs 19–41 View FIGURES 19–31 View FIGURES 32–36 View FIGURES 37–41 , Fig. 24 View FIGURES 19–31 represents the lectotype)

Basionym:— Stauroneis anceps f. indica in Gandhi 1959a, Ceylon Journal of Science (Biology Section), p. 104, 105, fig. 25 (here reproduced as Fig. 19 View FIGURES 19–31 ).

Type:— INDIA. Dharwar, Karnataka. Dharwar pools from paddy and millet fields watercourses during rains, 15°26’34.8” N, 74°54’43.2” E. Mr. H. P. Gandhi on 14 th August 1949 GoogleMaps .

Lectotype (designated here):—Agharkar Research Institute ( AHMA) Gandhi Collection! Slide- Sr 48, here illustrated as Fig. 24 View FIGURES 19–31 .

Description:—LM ( Figs 19–31 View FIGURES 19–31 ): Valves broadly lanceolate with constricted, subrostrate to rostrate apices. Length 32.0–64.0 µm, breadth 12.0–15.0 µm. Axial area narrow, widening at centre. Stauros bow-tie shaped, widening towards valve margin. Raphe slightly coarse with straight central raphe ends, terminal raphe fissures unilaterally deflected. Striae strongly radial punctate, 17–19/10 µm. Areolae punctate to transapically elongated, discernible in LM. (n= 36).

SEM ( Figs 32–41 View FIGURES 32–36 View FIGURES 37–41 ): Externally ( Figs 32–36 View FIGURES 32–36 ), valves linear-lanceolate with axial area narrow throughout but wider at centre ( Figs 32, 36 View FIGURES 32–36 ). Central raphe ends tear-drop shaped ( Figs 32, 33 View FIGURES 32–36 ). Terminal raphe fissures continuing onto mantle ( Figs 34, 35 View FIGURES 32–36 ). Striae uniseriate, composed of transapically elongated areolae, 24–28 in 10 µm ( Figs 33–35 View FIGURES 32–36 ). Internally ( Figs 37–41 View FIGURES 37–41 ), stauros broad, thickened and expanded ( Figs 37, 38, 40 View FIGURES 37–41 ). Central raphe ends slightly deflected, terminating onto well-developed stauros ( Figs 38, 40 View FIGURES 37–41 ). Terminal raphe fissures terminating onto helictoglossae ( Figs 38, 39 View FIGURES 37–41 ). Striae radiate, areolae with hymen occlusions ( Figs 39–41 View FIGURES 37–41 ).

Remarks:—Valve dimensions of the specimens examined in the present study have a wider size range than H. P. Gandhi in the original description- length 54.0–58.0 µm; width 14.4 µm (see Table 2 View TABLE 2 ). This taxon is also observed in Sr 46, collected by H. P. Gandhi from the same site at the same time and date as Sr 48.

Etymology:—The specific epithet “ dharwarensis ” refers to the type locality Mugad, Dharwar district, Karnataka, where H. P. Gandhi originally collected the sample.