high CPU time in the phase "Execute" for select statement in tkprof

Hi,

We have the following select:

output tkprof :
--------------------

SELECT TOTCON_VALOINDI_, TOTCON_TIPOLIQU_
FROM   TOTCON
WHERE  TOTCON_ESCENA_CODIGO___ = :B5
AND    TOTCON_INDICA_CODIGO___ = :B4
AND    TOTCON_ENTIDA_CODIGO___ = :B3
AND    TOTCON_TIPOACCI_        = :B2
AND    TOTCON_TIPOCOTI_        = :B1
AND    TOTCON_FECHINIC_        = (SELECT MAX(TOTCON_FECHINIC_)
                                  FROM   TOTCON
                                  WHERE  TOTCON_ESCENA_CODIGO___ = :B5
                                  AND    TOTCON_INDICA_CODIGO___ = :B4
                                  AND    TOTCON_ENTIDA_CODIGO___ = :B3
                                  AND    TOTCON_TIPOACCI_        = :B2
                                  AND    TOTCON_TIPOCOTI_        = :B1
                                  AND    TOTCON_FECHINIC_        < :B6
                                 )

call     count       cpu    elapsed       disk      query    current        rows
------- ------  -------- ---------- ---------- ---------- ----------  ----------
Parse        2      0.00       0.00          0          0          0           0
Execute    544     59.68      65.80        921     502112          0           0
Fetch      544      0.10       0.08          2       2176          0         544
------- ------  -------- ---------- ---------- ---------- ----------  ----------