SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '399a3be2e333873f684bb85ea8bcd4b6fc7923ea03cffcabf1239c9b80b39dec' 
  AND token = 'IqwEz4Ihqmlc3GpXWGG+XwkBywxazzRlOLdStqPflNc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

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