Cymbella tumidula var. procera (Krammer) W.Silva, 2015

Silva, Weliton Jose da, Jahn, Regine, Ludwig, Thelma Alvim Veiga, Hinz, Friedel & Menezes, Mariangela, 2015, Typification and taxonomic status re-evaluation of 15 taxon names within the species complex Cymbella affinis / tumidula / turgidula (Cymbellaceae, Bacillariophyta), PhytoKeys 53, pp. 1-25 : 6-8

Cymbella tumidula var. procera (Krammer) W.Silva comb. nov. Figs 57-63

Basionym.

Cymbella affinis var. procera Krammer, Diatoms Europe 3: 161, Figs 22: 8-13, 2002.

Holotype.

Preparation 714 IOK, in the Alfred-Wegener-Institut für Polar- und Meeresforschung (BRM), Bremerhaven, Germany.

Lectotype

(designated here). An individual on preparation 714 IOK, in the Alfred-Wegener-Institut für Polar- und Meeresforschung (BRM), Bremerhaven, Germany, represented by Fig. 57 .

Type locality.

Serbia, Rogatica (abundant in chalk-rich spring), 1976.

Valves lanceolate, dorsiventral, dorsal and ventral margins convex; ends subrostrate or subcapitate; length 27.0-40.3 µm, breadth 9.0-10.2 µm, L/B ratio 2.9-4.2; axial area linear-lanceolate, slightly arched, central area rounded; striae 9-13 in 10 µm, becoming 13-18 toward ends, 2-5 isolated pores; 25-31 punctae in 10 µm.

Remarks.

According to Krammer (2002), this variety differs concerning wider valves (higher than 9.5 µm) from the nominate variety of Cymbella affinis sensu Krammer. We recorded specimens of Cymbella tumidula var. procera with 9 µm breadth, which were higher than the nominate variety (9.0-10.2 vs. 7.8-8.7 µm).

Specimen designated by Krammer (2002), i.e., the preparation 714 IOK (BRM), were found to belong to more than one taxon. Therefore we designated a lectotype as established in Art. 9.11 of the ICN ( McNeill et al. 2012).

Figures

Figures 43 - 63. Cymbella tumidula species complex 43 Original illustration provided by Grunow in Schmidt (1875, Pl. 9, Fig. 33), lectotype, here designated 44 - 49 Cymbella tumidula var. tumidula, specimens from Trieste in preparation BM 18543 49 Epitype, here designated 50 - 56 Cymbella tumidula var. tumidula [Cymbella affinis sensu Krammer (2002)], specimens from Trieste in preparation 1131 G IOK 54 Isolectotype, designated here 57 - 63 Cymbella tumidula var. procera (Krammer) W. Silva, specimens from Serbia in preparation 714 IOK, holotype 57 Lectotype, designated here. Scale bar: 10 µm.