Raphidiopsis (Fritsch & Rich) Anguilera, Berrendero Gómez, Kaštovský, Echenique & Salerno (2018: 144)

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

Raphidiopsis (Fritsch & Rich) Anguilera, Berrendero Gómez, Kaštovský, Echenique & Salerno (2018: 144)

Type: R. curvata Fritsch & Rich (1929: 91)

Filamentous, planktonic; trichomes solitary, without sheaths or gelatinous envelopes, straight, waved or screw-like coiled, isopolar, uniseriate, with or without heterocytes. When heterocytes are present, they are in the terminal position, oval, ovoid or conical, sometimes slightly curved and drop-like, developing at one or both ends of the trichome. Trichomes without heterocytes usually attenuated toward both ends, but without hair-like, elongated apical cells, ± constricted at the cross walls, sometimes indistinct.Vegetative cells barrel-shaped, always longer than broad, sometimes slightly elongated towards the trichome ends, facultatively with aerotopes; apical cells conical-rounded or sharply pointed. Akinetes intercalary, barrel-shaped, oval or cylindrical, single or multiple in series, developing towards the middle of trichomes.

A widely distributed genus of 19 species known from freshwater lakes, reservoirs and rivers. Here three species are described from north-eastern Australia. Bibliography: Seenayya & Suba Raju (1972), Baker (1991), Komárek & Kling (1991), Fabbro & Duivenvoorden (1996), Padisák (1997), McGregor & Fabbro (2000), Komárek & Komárková (2003), Li et al. (2008), Moustaka-Gouni et al. (2009), Stüken et al. (2006, 2009), Kling (2009), Moustaka-Gouni et al. (2009), McGregor et al. (2011), Piccini et al. (2011), Komárek & Mareš (2012), Moreira et al. (2015), Antunes et al. (2015), Komárek (2016), Li et al. (2017), Komárek (2016), Aguilera et al. (2018).

1. - 2. - Trichomes always lacking heterocytes...............................................................................................................................................2 Trichomes with terminal heterocytes ............................................................................................................................. R. raciborskii Trichomes c-shaped curved, sigmoidally or irregularly circular......................................................................................... R. curvata Trichomes straight or slightly bent............................................................................................................................ R. mediterannea