SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be3e16f510643c3d11fae10f2520e966f2e7cb1dea9e1e141085010689a53671' 
  AND token = 'Q+yHwX5pk8HTxlKeCyh/mODg7wCAwf/yARj9E02j5oY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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