SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2eec1e1f65c1dbc98b91a41b583052559f21f09c85acc6b140e3b85f9557f69d' 
  AND token = 'Fh+CS+tjW0DdpQumUJkvNAjyJDxc2Dm4zjYa80JmvcU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}