SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6153e956415f6be3db1f5112cebe854893943005fd6397781b50ab9687b93783' 
  AND token = 'KLpOhonQm9EXUeipFwPQRhxdcxo4cJYTV/Hmz/3qTuQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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