SELECT 
  1 
FROM 
  vi_lock_keys 
WHERE 
  key_id = '5a50454feb9b2c839faf670e95e7c2fe027558642bd957eeaa7d9dfbbd727ce2' 
  AND token = '/Nk+gNBgmJ+qS6Jbih98F7Az/GN3HgBGKDAz9Y0wkSc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

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