Hyalotheca dissiliens Brébisson ex Ralfs var. dissiliens, Ralfs, BritishDesmidieae.

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 : 7-8

Hyalotheca dissiliens Brébisson ex Ralfs var. dissiliens , Ralfs, BritishDesmidieae. 51, pl. 1, fig. 1a-i. 1848.

( Figs. 16 A-B)

Cells 1.2 times greater in length than width, 23-26 × 20- 22 μm, 18-20 μm broad at the apex. Semicells pyramidal-truncated with rounded angles; straight to slightly convex lateral margins; truncated apical margins; shallow median constriction; open median sinus.

Material examined: BRAZIL, AMAPÁ, Macapá, Curralinho Lake , 02.VI.2007, C.B. Araújo (SP469217) .

Comments: this species presents particular morphometry with an arrangement of apical pores and a lobed axial chloroplast, similar to those of Desmidium siolii Förster that was proposed by Förster (1969) based on specimens collected in Pará state. According to Martins (1980), the main difference between the above two species is their cell division process, which results in an invagination of the cell wall in Desmidium .

Distribution in Brazil: Amazonas ( Thomasson 1955, Uherkovich & Schmidt 1974, Uherkovich & Rai 1979, Sophia & Dias 1996, Melo & Souza 2009, Souza & Melo 2010); Goiás ( Felisberto & Rodrigues 2002, Nogueira et al. 2016); Pará (Förster 1969); Paraná (Bittencourt-Oliveira 1993b, Felisberto & Rodrigues 2011); Rio Grande do Sul ( Rosa et al. 1987, Rosa et al. 1988, Burliga et al. 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.