SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f166e8f75f35eb5b7a1d7b4e22af838586ed5c40bd84d500df47bb90b813183' 
  AND token = 'hYog9RbuEWLWsY15ZWpNGjXk+WZDf8mFR8h/mmXUCvU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}