SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd85bed4f5fb8254c568c784e94743b9083646e75328635a103164695f5f64dfb' 
  AND token = 'SmpDwjXJ8PlAegLxzHBg/gZFXd7cMk3mRR/E4QDwRIw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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