The smaller forms of Mondo Grass are sometimes called
Ophiopogon japonicus 'Nana', but they are all the same species. The largest forms of Mondo Grass can look similar to Creeping Lily Turf (
Liriope spicata), but usually the leaves are somewhat narrower.
My favourite is Black Mondo Grass (
Ophiopogon planiscapus 'Nigrescens'), even the berries are black, instead of blue. It is a slower grower, often grown in containers, but I have seen in-ground plantings several feet wide. Fun fact:
Ophiopogon means 'snake grass' in Greek.
@DirtMechanic: Are those photos of a public garden or your private domain? It looks quite spacious.