SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa9ba81936bb93dec65bb1bf94f20d930872459eab8b702500cf761e46b9295f' 
  AND token = '3R5h0HOHtGRyUl9+y+YMjwtUmVKKWHByp1NfVHEWlg4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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