SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8dccdb39ff6dd8eec652914cc6d9366f03a4af95e7253ae6a3716b8b4b927aa6' 
  AND token = 'uqzUtMVHRqHeR0GQcvHSW0uifpd32WA1d6DqHUjJtpU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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