Spondylosium desmidiiforme (Borge) G.S.West

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 : 10

Spondylosium desmidiiforme (Borge) G.S.West , Journal of Botany 42: 286, pl. 464, fig. 11-12. 1904.

Sphaerozosma desmidiiforme Borge , Arkiv för Botanik 1: 120, pl. 5, fig. 23a-c. 1903.

( Fig. 20 )

Cell 2.3 times broader than long, 10 × 24 μm and 21 μm broad at the isthmus. Semicells oblong and narrow; lateral margins broadly round; broadly truncated apical margin; concave basal margin; easily visible and shallow median constriction; broad median sinus; axial chloroplasts.

Material examined: BRAZIL, AMAPÁ, Macapá, Curralinho Lake , 15.IV.2008, C.B. Araújo (SP469226) .

Comments: according to Bicudo & Samanez (2016), the original description of Spondylosium desmidiiforme (Borge) G.S.West was reported by Borge (1903) as Sphaerozosma desmidiiforme Borge , and the material collected in Rio Grande do Sul state. Förster (1969) observed variation in the cell measurements, as well as in the open median sinus of semicells of the f. tenuius Förster that he examined. Based on this information, Bicudo & Samanez (2016) considered Spondylosium desmidiiforme var. desmidiiforme f. tenuius and Spondylosium desmidiiforme var. desmidiiforme f. desmidiiforme identified by Förster (1964) as heterotypic synonyms, since they found no difference between the circumscriptions of both these taxa.

Distribution in Brazil: Amazonas (Thomasson 1971, Förster 1974, Martins 1980, Souza 2008); Bahia (Förster 1964, Martins & Bicudo 1987, Bicudo & Martins 1989, Oliveira et al. 2010, Oliveira 2011); Pará ( Scott et al. 1965, Förster 1969); Paraná (Bittencourt-Oliveira 1993b); Rio de Janeiro ( Sophia 1987); Rio Grande do Sul ( Borge 1903, 1918); São Paulo ( Bicudo & Samanez 1984, 2016).

Figures

Figs. 16-23. Pseudofilamentous desmids of Curralinho Lake, Macapá,Amapá, Brazil. 16 A-B. Hyalotheca dissiliens var. dissiliens. A. fungi in the cell wall of the algae, B. detailed cells; 17 A-B. H. javanica. A. detailed pseudofilament, B. detailed cells; 18. Mateola curvata; 19 A-B. Phymatodocis nordstedtiana var. nordstedtiana f. minor. A. pseudofilament frontal view, B. pseudofilament lateral view; 20. Spondylosium desmidiiforme; 21. S. pulchrum var. pulchrum; 22. S. rectangulare var. rectangulare; 23 A-B. S. rectangulare var. goyazense, detailed cells and pseudofilaments. Scale bars = 10 µm.