Desmidium graciliceps (Nordstedt) Lagerheim var. groenbladii C.Bicudo & Samanez

Araújo, Camila Barbosa de, Bicudo, Carlos Eduardo de Mattos, Takiyama, Luís Roberto & Melo, Sérgio de, 2020, Pseudofilamentous desmids (Zygnematophyceae) from an Amazonian floodplain lake (Macapá, AP, Brazil), Iheringia, Série Botânica (e 2020010) 75, pp. 1-14 : 5-6

Desmidium graciliceps (Nordstedt) Lagerheim var. groenbladii C.Bicudo & Samanez , Bibliotheca Phycologica 68: 39, fig. 11. 1984.

( Fig. 9 )

Cell 1.6 times greater in length than width, 43-48 × 23- 26 μm, 9-10 μm broad at the apex and 18-19 μm broad at the isthmus. Semicells pyramidal-truncated; straight apical margin; convergent undulated lateral margins with slight concave at the subapical region; rounded basal angles; shallow median constriction; open to linear median sinus; hyaline to light brown cell wall; axial chloroplast.

Material examined: BRAZIL, AMAPÁ, Macapá, Curralinho Lake , 03.VII.2007, C.B. Araújo (SP469218), 15.IV.2008, C.B. Araújo (SP469226), 15.VII.2008, C.B. Araújo (SP469228) .

Comments: this species has longer cells with broader apices than D. graciliceps var. graciliceps (Nordstedt) Lagerheim. Grönblad (1945) identified samples as D. graciliceps var. groenbladii as form “ gracilius ”, and later, Scott et al. (1965) and Förster (1969) identified their samples as var. “ gracilius ”. Despite neither the form nor the variety were ever formally proposed, Bicudo & Samanez (1984) designated specimens of this kind representative of D. graciliceps var. groenbladii Bicudo & Samanez.

Distribution in Brazil: Bahia ( Oliveira et al. 2010); Pará ( Scott et al. 1965, Förster 1969); São Paulo ( Bicudo & Samanez 1984, 2016); Federal District ( Leite & Senna 1992).

Figures

Figs. 3-15. Pseudofilamentous desmids of Curralinho Lake, Macapá, Amapá, Brazil. 3 A-C. Bambusina borreri. A, B. detailed cells; C. detailed pseudofilament; 4. B. borreri var. brasiliensis; 5 A-B. B. borreri var. majus, detailed cells and pseudofilaments; 6. Desmidium baileyi var. baileyi f. bailey; 7 A-B. D. elegans. A. detailed pseudofilament, B. detailed cell; 8 A-B. D. graciliceps var. graciliceps. A. frontal view of the pseudofilament, B. slight modification of the pseudofilament frontal view; 9. D. graciliceps var. groenbladii; 10 A-C. D. longatum. A. pseudofilament frontal view, B. formation of the elongate conjugation tube, C. zygospore; 11 A-B. D. quadratum var. quadratum. A. detailed pseudofilament, B. detailed cells; 12. D. quadratum var. constrictum; 13 A-B. Groenbladia neglecta var. neglecta. A. detailed pseudofilament, B. detailed cells; 14 A-B. G. neglecta var. elongata. A. detailed pseudofilament, B. detailed cells; 15. Haplozyga armata var. armata. Scale bars = 10 µm.