Chroothece richteriana Hansgirg

Ganesan, E. K., West, John A. & Jr, Orlando Necchi, 2018, A catalogue and bibliography of non-marine (freshwater and estuarine) Rhodophyta (red algae) of India, Phytotaxa 364 (1), pp. 1-48 : 7-8

Chroothece richteriana Hansgirg

Iyengar 1985, p. 1, figs 1–11; Desikachary et al. 1990, Part II A. p. 7, fig. 1 a–f.

Distribution in India: Tamil Nadu (Teynampet, Chennai, on the moist inner side of a wall of an irrigation well of slightly brackish water located inside the Agri-Horticultural Gardens, now renamed Semmozhi Poonga).

Notes: Two other genera, Petrovanella Kylin and Vanhoeffenia Wille in Drygalski are currently treated as synonyms of Chroothece ( Schneider & Wynne 2007; Ott 2009). Kumano (2002) dealt with only four unicelluar genera ( Porphyridium, Cyanidioschyzon De Luca, Taddei & Varano , Cyanidium Geitler and Galdieria Merola , the last three genera occurring only in extremophilic conditions) and excluded some other well-known unicellular or colonial red algae like Chroothece, Glaucosphaera Korshikov and Rhodosorus Geitler. The reports of Chroothece range from sub-aerial substrata like wet brick walls ( Islam 1972, 1992; Iyengar 1985), the mountain stream of Cuba (Reith 1973), British Isles ( Pentecost et al. 2013) peat bogs ( Sheath & Sherwood 2016) and the extreme conditions like the thermal springs of Iceland ( Pentecost 2011). Islam reported as early as 1972, Chroothece for the first time from a tropical region ( Bangladesh, then East Pakistan) as Petrovanella mobilis (Pascher & Petrova) Kylin (= C. mobilis ). Later, Iyengar (1985) recorded and illustrated in detail Chroothece richeterina from a more southern latitude in South India. Both Islam’s and Iyengar’s papers were apparently unknown and not accessible to most phycologists in Europe and America. Ott (2009) proposed a new order and a family to include Chroothece and the pseudofilamentous Chroodactylon . His conclusion is based on “the close similarity of the chloroplasts of these two genera”. Molecular evidence provided by Yoon et al. (2006) place Chroothece with Chroodactylon clade, thus supporting the conclusion of Ott. Aboal et al. (2014 a, b) investigated the ecology, morphology, physiology and lipid content of C. richteriana from a highly calcareous river in Spain. Aboal et al. (2018) provide molecular evidence that Chroothece is distinct from Chroodactylon . Brief mention should be made that Lewin & Robertson (1971) cultured Chroodactylon (= Asterocytis ) in quarter-strength seawater causing it to switch from filamentous to uni- and bi-cellular growth, similar to Chroothece .

Genus - Kyliniella Skuja