SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1597cfd82eb45b524db2f69cca3ae023468ae8bf4698990520a42fdbcf9dc29' 
  AND token = 'C7AzfNoiNa2xwMis/Utp09SYvgQgGj9p1bwBVzHutKA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}