SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23e2c122af082eec6aa3ff42b2940cac69e2ba4ab0404c273769cc87c5fe4d2a' 
  AND token = 'RKK4matWXX8DqPid8EKd7ueTkjksi4ntxeIPk+9iK68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

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