SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef3406a3785b0a8db13e636de6b035b1caf8acafa360e7f8d484457dc7086a3a' 
  AND token = 'ljqi/Jq2ZxT8euVxvs/FdHzuRrFpkGvBJVulEG2Yc9o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

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