Anabaena torulosa Lagerheim ex Bornet & Flahault (1886: 236)

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

Anabaena torulosa Lagerheim ex Bornet & Flahault (1886: 236) Fig. 37 C–F .

Filaments benthic, often tycoplanktonic; trichomes solitary, growing amongst other algae or forming prostrate mats, straight or flexuous, cylindrical, distinctly constricted at the cross walls. Vegetative cells barrel-shaped, ± isodiametric, (2.0–) 3.5–5.0 μm long × 4–7 (–8) μm broad, blue-green in colour; apical cells conical. Heterocytes solitary, spherical to ovate, 6–10 μm long × 6–8 μm broad. Akinetes solitary or in series, widely cylindrical, flatly rounded at the ends, (5.5–) 14–24 (–28) μm long × (5–) 7–12 μm broad, epispore smooth, brownish-green in colour, adjacent to and on either side of the heterocytes.

Specimens examined:—Bill Gunn Dam, Burnett R. at Ned Churchward Weir, Fairbairn Dam, Paradise Dam, Sandy Ck at Wivenhoe-Somerset Rd Crossing, Sheepstation Ck at Kilcoy-Murgon Rd.

Other records:— Queensland: SE Queensland, McLeod (1975); South Australia, River Murray at Ross Lagoon, Warren Res., Strathalbyn Res., Bundaleer Res., Baker (1991), Ling & Tyler (2000).

Observations:—Growing on the benthos in shallow littoral areas of lakes and backwaters of streams, usually on fine, unconsolidated sediments. Considered a cosmopolitan species with a wide distribution (Komárek 2013).

Figures

FIGURE 37. A–B Anabaena inaequalis; C–F Anabaena torulosa. Scale bars = 20 μm