Malformations in Cymatopleura solea
	Cymatopleura solea will serve as a further example of malformations that occur in older cultures. Diatoms of this species were isolated from Lake Ebnisee (48°55'25.5"N 9°36'32.8"E) on 25 March 2017 and kept in clonal culture. About every other week diatoms of a parent culture were inoculated into a subsequent culture. The video at the top shows (30x time lapse) a view into such a culture taken on 16 May 2017. At that time, the diatoms still had an almost uniform length of about 160 µm. In the following months a gradual reduction of the diatoms was observed. Malformations occurred in larger numbers from August 2018. The following video is taken on 7 November 2018:
	(20x time lapse when using 10x objective; 10x time lapse at higher magnifications) The length of the diatoms was typically in the range of 55 µm to 75 µm. The arched deformed diatoms, however, had a length of only about 45 µm (distance from apex to apex). The following picture gives an impression of the valves of such diatoms:
	The left valve shows only a slight asymmetry with respect to the apical axis.
	Thomas Harbich   http://diatoms.de/en/culturing/challenges