SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6b28a460c299fcce35ecbb6467d8161f7c4bbcd5c832a7379298e9cf4fa9466' 
  AND token = 'xwPqvEje84+YGkwD+S8zMK0DDU6vNeChAHsTrFMgqrI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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