|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Bivalvia - Protobranchia - Nuculanidae
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 and thin, sub-oval in outline ; posterior end rostrate
and pointed ; anterior end regularly and broadly rounded, ventral margin
curved, posterior end sloping at an angle of 30 to the ventral line terminating
at the dorsal margin in a beak; posterior dorsal margin directed downward and
concave; lunule narrow and elongate, only slightly impressed and limited by a
fine line ; escutcheon narrow and impressed ; surface ornamented with concentric
ribbing which continues from the anterior margin, regularly to the rostrum, the
ribs are numerous with only slight interspaces, they are prominent and have the
appearance of slightly overlapping each other from the ventral region toward the ambones ; a faint groove extends from the beaks to the posterior point of the
ventral margin, just back of which the concentric sculpture is somewhat obliterated
except for faint lines of growth.