SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a5455d2228ef72dea3d6c312c3db74e1aaf7962efa9c70fb1013af2d7736613d' 
  AND token = 'XbjbxcPG2SoBDxIX8eob0h2BHDVtJhGuO5NN4OzPvtA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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