SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6cdd2399969cc3d86be1c859d6529a21bca0d322fa6a1eef889d7cce77b5c8d9' 
  AND token = '3nFo5SGaOzpGUDptJfYHRilcdHfuKCmRUerHL5eHAfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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