Monk strain was introduced into China about 70 years ago, whereas Daruma strain (in China we call it Ribenlan, means Japanese clivia or "Ribenlan" in Chinese pronunciation) originated in Japan and was intruduced into China about 18 years ago.
The difference between typical long leaf Monk and Mid-leaf Monk and typical Daruma plants is obvious. First, the leaves of Monk plants are longer (usually between 300 mm to 500 mm long, 90 mm to 110 mm wide). we have long leaf Monk (leaves over 450 mm long), Mid-leaf Monk (leaves between 350-450 mm) and Short Leaf Monk (leaves within 350 mm), among them Short Leaf Monk is the best. The ratio of length to width is between 3:1-5:1. The leaves of Daruma are usually shorter (usually between 200 mm to 300 mm, and 90 mm to 120 mm wide, some can be as wide as 150 mm wide or even wider), the ratio of length to width is between 1.5:1-2.5:1. Second, the leaves of Monk are brighter than those of Daruma, the veins are more obvious than those of Daruma. Third, the leaves of a typical Daruma plant are usually pendulous, whereas the leaves of a typical short leaf Monk is upright.
Now, a lot of clivia breeder in China cross short leaf Monk, Round Tip Short Leaf (another famous Chinese clivia cultivar, which is a hybrid between Monk and Dye Factory and Short Leaf) with Japenese Daruma to produce shorter and broader leafed cultivars. As a result, a series of cultivars were created. Such as Henglan, with the ratio of length to width being 1:1-1.5:1; Steel City Short Leaf, actually a Daruma, with the ratio of length to width being 2:1 and very broad leaf (can be over 130 mm wide, the widest leaf I have ever seen is 170 mm wide and about 350 mm long). If the progeny resembles Monk, we still call it a Monk; if the progeny resembles Daruma, I will call it a Daruma (acutually Chinese enthusiasts will call it Anshan clivia or Japanese clivia hybrid), or actually, they can be called Chinese Daruma, which is different from original Japanese Daruma.
You can have a look at some Daruma plants, short leaf Monk plants and seedlings at photo gallary and plants for sale portion.