SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c2bc49cbec977b883e3c4ae5ac4c552f66e9bdcb222ac61cd9482491ae549f0' 
  AND token = 'CcoP2to7TrOChHBbOYu1XZ1CSvzYMD0HrQKCP89LzJ0=' 
  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"
    }
  }
}