SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0877b62dc37b8008a69ab644a603540b909088b91042f5d3637cb5640fccc4fc' 
  AND token = 'ieMBBdiwXeJr2G9tC1jg4GUy6OWFUkweMLaBBVGWPg8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

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