Loch Ness Clan
The Loch Ness Clan has been in existence since at least the 10th century (Prince Malcolm and Robbie may have had an encounter with the clan by 967). ("Once Upon A Time There Were Three Brothers...") Most likely, they had contact with many neighboring clans including the Wyvern Clan, and the Scone Clan.  It doesn't seem likely that they had any contact with Demona's Clan as she seems to think all gargoyles were eradicated from Scotland by the Hunters. The London Clan has also been aware of the clan's existence, though its unknown if the London Clan is aware that the Loch Ness Clan has survived to the present day. 
The Clan lives in partially submerged caverns beneath the Loch and their primary mission is to protect and safe guard the few remaining Loch Ness Monsters that still survive under the lake's surface.  While it is unclear where the clan was when Sevarius captured "Nessie" in early 1996, they were aware that she was missing, but did not know the cause of the creature's disappearance.  Any help they might have given was not seen by the Avalon world tour travelers or Sevarius in the murky loch. 
Easily the most aquatic of surviving gargoyles, the Loch Ness Clan has adapted well to their watery dwellings. Their wings are shaped as large manta-like fins and their lower bodies are quite dolphin-esque. It is unknown how these features have affected their ability to walk on land, glide, etc. 
There are currently no known members of this clan.