SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '75ac0461133df86830b5b8e1fd16e0ce4556add1f9766c17a170f27d423f7917' 
  AND token = 'jXcENBEln+U5DAGB4bWJgKNmIhg2PvvD37JnVsVZPoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables