replum

Replum widely expanded at base, narrowly flattened elsewhere;
假隔膜广泛地扩大在基部，在别处勉强使变平；
Replum strongly flattened, base much broader;
Replum rounded, concealed by connate valve margin;
Replum rounded, concealed by connate margins of valves;
Replum rounded, covered by connate valve margin;