Freshwater Cyanobacteria of North-Eastern Australia: 3. Nostocales Author Mcgregor, Glenn B. text Phytotaxa 2018 2018-07-09 359 1 448 450 http://dx.doi.org/10.11646/phytotaxa.359.1.1 journal article 10.11646/phytotaxa.359.1.1 1179-3163 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