Cosmarium pseudoconnatum Nordstedt (1870: 214)

Ramos, Geraldo José Peixoto, Bicudo, Carlos Eduardo De Mattos & Moura, Carlos Wallace Do Nascimento, 2018, Some new, rare and interesting desmids from bromeliad phytotelmata in Brazil, Phytotaxa 346 (1), pp. 59-77 : 65

* Cosmarium pseudoconnatum Nordstedt (1870: 214) ( Figs 44–48 )

Cell dimensions: 44–48 μm length, 33–35μm width, 31–33 μm isthmus.

Material examined: BRAZIL, Bahia, Santa Teresinha, Serra da Jiboia. 14-I-2015, G. J. P. Ramos et al. s/n ( HUEFS 224658), 18-VII-2015, G. J. P. Ramos et al. s/n ( HUEFS 224682), 11-IX-2015, G. J. P. Ramos et al. s/n ( HUEFS 2246703), 20-XI-2015, G. J. P. Ramos et al. s/n ( HUEFS 224720).

Habitat: bromeliad tanks ( Alcantarea nahoumii ); T 28.1 (± 2.0 ºC). pH 6.2 (± 0.4). C 0.30 (± 0.15 mS. cm-1). TDS 0.17 (± 0.12 ppt). DO 7.4 (± 3.5 mg.L- 1).

Notes: During our analysis, we noted variations in the chloroplasts of this species, from 4-radial (most common) to 5-radial. Morphologically, C. pseudoconnatum can be easily confused with Cosmarium connatum Brébisson ex Ralfs. The most important difference is the shape of the chloroplast in apical view: 2-radial in C. connatum , at least 4-radial in C. pseudoconnatum .

Figures

FIGURES 26–48. Cosmarium majae: LM (26–33); SEM (33), ventral view (27, 29–31, 33), apical view (26), lateral view (28) and zygospore (32); C. oliveirae: LM (34–37); SEM (38), ventral view (34–35, 38), apical view (36), lateral view (37); C. pachydermum var. aethiopicum: LM (39–42); SEM (43), ventral view (39–40, 43), lateral view (41), apical view (42); C. pseudoconnatum: LM (44–47); SEM (48), ventral view (44–45, 48), apical view (46–47). Scale bar 10 μm (26–32, 34–38, 44–47), 5 μm (33), 20 μm (39–43).