Base tables that have a unique constraint but not the primary key

SELECT A.table_schema, A.table_name 
FROM INFORMATION_SCHEMA.tables A
INNER JOIN INFORMATION_SCHEMA.schemata B
ON A.table_schema=B.schema_name
WHERE (A.table_schema, A.table_name) NOT IN 
(SELECT table_schema, table_name FROM INFORMATION_SCHEMA.table_constraints
WHERE constraint_type IN ('PRIMARY KEY'))
AND (A.table_schema, A.table_name) IN 
(SELECT table_schema, table_name FROM INFORMATION_SCHEMA.table_constraints
WHERE constraint_type IN ('UNIQUE'))
AND A.table_type='BASE TABLE'
AND (A.table_schema = 'public'
OR B.schema_owner<>'postgres')
ORDER BY A.table_schema, A.table_name;