SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '83f0de1eaca4c980c0a5eec092f04f4780e122c76b38dc6abd0a4a322baef172' 
  AND token = 'uqpswWBSkvI1zBUFmW/rlJGQZa9TbfeXmKX5wcc6UCA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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