I had a table defined with a partitioned primary key. In order to load the data, I issued
ALTER TABLE SCHEMA.TABLE_NAME DISABLE CONSTRAINT PK_TABLE_NAME;
After this alter was issued, the index entry vanished from DBA_CONSTRAINTS, DBA_IND_PARTITIONS. When I enabled the index, the index was created as a non-partitioned index. In order to get past this, I had to change the alter to
ALTER TABLE SCHEMA.TABLE_NAME DISABLE CONSTRAINT PK_TABLE_NAME KEEP INDEX;