SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8947eeb95dccd209c49d856d8e3af16223ee7d8ddbc811af941ef6b26a3673c7' 
  AND token = 'k2jM0X5zbxHnlbMh+OA4qB4pp+4pQoH58wpGIQKDijw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00143

JSON explain

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