SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12a41a9bb868593a1507c09072848720fcaed36a2503c31b62e4c2821500bfd3' 
  AND token = 'kF64q6RUr5C5EA+YKkcCY4/4aaSu9QZuq5xpS09t8SA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

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