SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0600ccc7969d63104f6f6157e66916967ffe07ec412fd8fbaa491b53f93f9045' 
  AND token = 'FfioF/G0NkcAwmk52900HN/JFOObW9iObKVsh3Clk9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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