SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '733216dbc3e16bf61f3881c86cdf245ce62485c22e724332e88ef5ddc26c2d55' 
  AND token = 'HnTiw8hxO5YalJUcbE8NTCfg18Ls3kJkBt7uqBkYUyc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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