SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '381a254c5d3be68a42c0969ccb354238111c92db424f0328975453c4597ff3f1' 
  AND token = 'GW1ujg0I0UQeAFmDpD4pJkNKz1wKgpGKANjgdpnA4kk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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