Mammillaria paulii sp. nov. ( Linzen )

First description by Thomas Linzen in Mitteilungsblatt des Arbeitskreis für Mammillarienfreunde 3/2005 134-145.
Body: Single, sometimes branching, depressed globose to almost globose, 4 - 8 cm in diameter and 3 - 8 cm high. Shiny dark green.
Roots: Thick, pulpous.
Sap: With watery sap.
Tubercule: Short cylindrical to conical, truncated top, 1,5 to 2 cm long, 0,8 to 1,2 cm in diameter. Spreading laterally somewhat compressed.
Axil: Naked .
Radial spine: (7) 9 - 11, thin, acicular, needle like, with darkbrown tip. Almost radiating horizontally, white-yellowish, later becoming greyish, 6 - 16 mm long.
Central spine: Absent.
Flower: Funnel form, 4 - 5 cm long and 4 - 6 cm in diameter. Sulphur yellow.
Fruit: Globose to little oval, 6 - 8 mm in diameter and about 9 mm long, dark green, later becoming green yellowish.
Seed:Drop-shaped, 2,0 - 2,3 mm long; 1,5 - 1,8 mm wide, black. Basal to subbasal
Habitat Substrate: On meadows with flat, strongly weather beaten lime rocks, in holes and sheltered by grass and moss.
Geographic Distribution: Mexico, San Luis Potosi near Mpio, Guadalcazar and Realejo.
Comments: Differs from the other species of dolichothele by having only radial spines, rounded form of the buds, building two rows of inner petals, globose fruits, the biggest seed in this group and a very rainy habitat separated from the other species of this series
Bibliography: AfM 3/2005


photo: W. Hellinx

Flower

Excellent! Thanks for sharing this lovely flower.

Central spine or not. I view this has nothing more than an extension of the population / habitat of M.sphaerica from Tamauilpas into SLP. I belive that given time more populations will be found inbetween.

One of my M. paulii's does produce an occasional central spine!

Wolter ten Hoeve.

It could just be an outlying population, only 120km as the crow flies from your WTH564, Wolter. That's not far for a species whose distribution starts some 400km away in Texas.

In AfM issue 3, 2005, Thomas Linzen considers M. melaleuca as the closest relative of M. paulii. I think that he is probably right.
M. paulii grows at a rather high altitude of 2000 meters and in a rather wet region. M. sphaerica grows at a much lower altitude and on the opposite side of the Sierra Madre Oriental where it is drier. M. melaleuca grows in the mountains near Miquihuana (it is still on my wish list to observe it in habitat) and, according to Thomas Linzen, in a similar habitat as M. paulii. The distance between M. paulii and M. melaleuca is a bit less than the M. paulii - M. sphaerica distance.


Wolter.

Thanks Wolter, that article was before I joined the AfM. Geographically, I can understand the logic. However, the similarities in spination and flower between sphaerica and paulii suggest otherwise, to a non-botanist at least, unless it is just a case of parallel development.

Taken today just to show the plants together. The ML 684 seed came from Lacoste via the Doug Rowland 2007 seed list, sown 25-2-07 and germniated 8-3-07. I have 4 of these plants remaining of which 2 plants have centrals ( one shown below ) and the other two plants do not.
Having looked at the plants this morning I can see why TL places them near M.melaleuca and given what wolter says about the habitats I would reaccess and place M.paulii n.n. has a form of M.melaleuca untill otherwise.