SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1cff08115f545127738b04e854221eec90306a67df2383037f1bd3facbe9df70' 
  AND token = 'FWXr//dvlGI1m7WxReNt8EDT4Qxoz6Aor2j8UsH/KMI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

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