Minangkabau keris, have a myriad of influence, Javanese, Buginese, Makassar and other Sumatran influences.
There are more '
patrem' sized kerises than the regular longer type kerises, possibly due to the matriarchal system which is practiced there.
The more common ones are the
bahari-class blades, which have a similar style like the keris panjang. In Peninsular Malaysia, the
bahari-class are known as
anak alang. As for the Javanese looking 'patrem' sized ones, a luk 3 are fairly common.
The sheath have a peculiar distinct shapes. There are a few variants.
For details, I would suggest getting one of these references:
1)
Karsten Sejr Jensen's, Krisdisk.
2) Vanna Ghiringhelli's, The Invincible Krises 2
Although The Invincible Krises 2 is not out yet, form what I was informed, it covers a fair bit of Minangkabau pieces, as well. 