SELECT 
  1 
FROM 
  vi_lock_keys 
WHERE 
  key_id = '4b8f4f6aa88f0f1cf8c11f29aca2b8e6256ed35dcd343f8fb53220b45cdcb135' 
  AND token = 'PQb7KjhVTZecolEhgYTj+kc2G2KT7pYAevuoTvRhjqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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