SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2d180f1f9de1bce2aa6b31306326bd5b25c99ba6ff207b1e4348014e3f7004c5' 
  AND token = '2DwFMaWXi0zYBKvLnzxCQHuwRd2I5kSRlZE+CWBtOVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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