Heterotopic position

Heteropolar

 

Heterovalvar

Applies to some concentrically undulate species of Stephanodiscus (e.g., S. aegyptiacus) where fultoportulae on the valve face are in the central area of the convex valve and in the marginal area of the concave valve. From Greek for “different place”.

See contrasting term, isotopic position.


Citations

Håkansson, H. and Meyer, B. (1994). A comparative study of species in the Stephanodiscus niagarae-complex and a description of S. heterostylus sp. nov. Diatom Research 9(1): 65-85. 10.1080/0269249X.1994.9705288

Houk, V., Klee, R. and Tanaka, H. (2014). Atlas of freshwater centric diatoms with a brief key and descriptions Part IV. Stephanodiscaceae B: Stephanodicsus, Cyclostephanos, Pliocaenicus, Hemistephanos, Stephanocostis, Mesodictyon & Spicaticribra. In: Poulícková, A. (ed.): Fottea 14 Supplement, 529 pp.