M. laui var dasyacantha or bocasana hybrid?

Spines are very soft with no centrals that I can see or feel. It clumps freely with each up to about 3-4cm in diametre. I've had the plant about 6 months. First 2 photos taken when purchased, last two photos taken today. Flowers are small, not more than about 1-1.5cm across. I was thinking Mam. laui var dasyacantha but the spines look too woolly and irregular to me. There is also a bocasana hybrid being sold (but not labelled as such in the shops) like this one on Ebay: http://cgi.ebay.com.au/MAMMILLARIA-BOCASANA-Cactus-Plant-/260352111351?pt=AU_Plants_Seeds_Bulbs&hash=item3c9e31f2f7 . It looks a lot like this. There are no hooked centrals. Is there a defining feature that identifies M. laui var. dasyacantha? Any ideas?

This looks like M. laui to me.

I have not seen before the plant being advertised as M. bocasana hybrid. If it is a hybrid, I wonder what it M. bocasana has been crossed with to look so alike to M. laui dasyacantha! It certainly has lost every characteristic of M. bocasana, the hooked spines, the radial spines, the flower colour, the woolly nature of the plant.

Do you think the advertiser has put the right picture into their advert?

Hi Chris,

She has been using the same picture now for over a year so I don't know... the only thing that makes me doubt the laui ID is that the spines seem a lot denser and irregular... all the photos I've seen of laui (of any variety) show a more uniform spination. The spines on this one are very soft too.

I shall email her and ask what the source is?