SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e59962f084f160339e41328f7d07e2b5dccf8486a525ed496d66a259dc69b6ea' 
  AND token = 'TBb2zZQUF7bshiv7Ip8wyGiCPsawSWynxoAXaHgAE/Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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