Since several important features were omitted from the original description, we here supply an improved diagnosis based on the original description and on information obtained during the present study.

Improved diagnosis of Glauconema trihymene: medium­sized marine Glauconema, trophont 30–36 × 16–24 m and tomite 30–40 × 8–15 m in vivo; cell shape reniform, bilaterally flattened with large apical plate in trophont, long oval shape with small apical plate in tomite. M1 three­rowed in trophont stage, reorganized to two rows and much more distant from M 2 in tomite stage. Scutica with several pairs of basal bodies arranged in short rows. Constantly 17 somatic kineties (SK); silverline of SKn (referring to the last SK counted from the right border of oral field; here equivalent to SK17) connecting with silverline of SK7 or SK8 on dorsal side. One macro­ and one micronucleus. Single contractile vacuole situated subcaudally on dorsal side, with contractile vacuole pore (CVP) at posterior end of SK2.

Deposited material: silver­impregnated voucher slide has been deposited in the Museum of Natural History, London, U. K. (registration no. 2006:4:3:1), additional voucher specimens remain in the authors’ slide collections in the Laboratory of Protozoology, Ocean University of China.