|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Bivalvia - Protobranchia - Yoldiidae
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
|C. E. Weaver and K. Palmer 1922||Shell small, plump, and subelongate in outline; inequilateral,
beaks situated not quite a third of the distance from the anterior end; ventral
and dorsal margins nearly parallel ; anterior dorsal margin sloping at about an
angle of 10 from the dorsal margin, rounded below into the ventral margin which
is only slightly rounded, posterior end extends upward at about an angle of 40
with the ventral margin, posterior terminating at the dorsal margin in a point;
posterior dorsal end concave; lunule faintly developed; escutcheon more deeply
impressed; surface smooth except for the concentric growth lines which are
fine and delicate; shell with a beautiful polish; outline of the teeth seen tnrough
the shell in the cardinal region.