Cronbergia siamensis (Antarikanonda) Komárek, Zapomělová & Hindák (2010: 329)

Mcgregor, Glenn B., 2018, Freshwater Cyanobacteria of North-Eastern Australia: 3. Nostocales, Phytotaxa 359 (1), pp. 448-450 : 448-450

Cronbergia siamensis (Antarikanonda) Komárek, Zapomělová & Hindák (2010: 329) Fig. 35 D .

Basionym: Anabaena siamensis Antarikanonda (1985: 345)

Filamentous; trichomes solitary amongst other algae or parallely aggregated into bright blue-green, mucilaginous mats, straight, short, up to 30–70 μm long, distinctly constricted at the cross walls. Vegetative cells cylindrical, isodiametric or longer than broad, without aerotopes, 2–5 μm long × 2–4 μm broad. Heterocytes spherical or subspherical, terminal at both ends of the trichome, 2–4 μm broad. Akinetes oval to subspherical, solitary or up to 3 or more in series, remote from heterocytes, 5–10 μm in diameter.

Specimens examined:—Rainbow Beach Fens, Great Sandy Natl Park, Cooloola Sect.

Observations:—Growing in the metaphyton of several shallow, peaty wetland pools amongst other algae and emergent vegetation. This material is consistent with the original description of C. siamensis from paddy fields in Thailand. However, trichomes were mostly singly dispersed amongst other algae, and did not form coherent thalli. Genuário et al. (2018) has recently shown that this species is phylogenetically aligned with the genus Cylindrospermum rather than Cronbergia .

CYLINDROSPERMUM

Figures

FIGURE 35. A–C Anabaena cf. alatospora; D Cronbergia siamensis. Scale bars = 20 μm