M. luethyi certainly has flowers reminiscent of M. theresae, but has been consistently placed with M. herrerae in the Lasciacanthae, not especially close to M. theresae. This is on the basis of the spines more than the flowers, numerous and not clearly distinguished into centrals and radials.
DNA analysis placed M. luethyi as an outlier amongst outliers, closest to the Ancistracanthae (US, Baja, and northern Mexican hook spined plants). It certainly has many features making it unique for the genus and not easy to place in any particular grouping. Compare to M. guelzowiana and M. barbata, also to Neollydia conoidea and Ortegocactus macdougalii, apparently its closest relatives genetically.
Wow, this sure seems like a "right" topic - very exciting to see the responses and all the Mammillaria flower pics. Daiv, it almost seems like this is a base to build a flower pic section. I am already using these to ID some of my plants that I was not sure about from the regular photos.
Here is another one of my Mammillaria flower photos.
Mammillaria rekoi ssp rekoi (aka M pullihamata)
I also want to say that I think an unsung hero here is Brad (Paracelsus), whose comment on the last contest led me to try and enter a more worthy photo in this contest. I would really like to see your photos back in the contest.
peterb wrote:Interesting that you see sphaerica for the Mammillaria I posted in the photo contest, Jordi. If so, it might not even be "from" Mexico.
peterb
My Mamm-book says, there are no spaerica any longer near Corpus Christi, TX. They can only be found south of the border in Tamaulipas, ie in Mexico.
Fantastic photos and "related" photos everyone. The only bad part about all of this is going to be trying to choose just ONE to vote for. There is no question I will be employing Brad's point system to figure this one out.
All Cacti are succulents, but not all succulents are Cacti
