Mother of Hundreds

Mammillaria compressa

(f. bernalensis)

mam-mil-AR-ee-uh  kom-PRESS-uh

Syn.

Mammillaria bernalensis, ETC.

  NOT Mammillaria tlayecac!!!

Synonyms of Mammillaria compressa DC. (48) (Updated on 12-7-23 from Plants of the World Online):  Cactus cirrhifer (Mart.) Kuntze (1891), Cactus compressus (DC.) Kuntze (1891)(nom. illeg.), Cactus conopseus (Van Houtte) Kuntze (1891),Cactus longisetus (Muehlenpf.) Kuntze (1891), Cactus squarrosus (Meinsh.) Kuntze (1891), Cactus subangularis (DC.) Kuntze (1891), Cactus triacanthus (DC.) Kuntze (1891), Mammillaria angularis Link & Otto ex Pfeiff. (1837), Mammillaria angularis f. compressa (DC.) Schelle (1907)(nom. illeg.), Mammillaria angularis var. compressa K.Schum. (1898), Mammillaria angularis var. fulvescens Salm-Dyck (1850), Mammillaria angularis f. fulvispina (K.Schum.) Schelle (1907), Mammillaria angularis var. fulvispina K.Schum. (1898), Mammillaria angularis var. longiseta (Muehlenpf.) Salm-Dyck ex K.Schum. (1898), Mammillaria angularis f. longiseta (Muehlenpf.) Schelle (1907), Mammillaria angularis var. triacantha (DC.) Salm-Dyck (1845), Mammillaria angularis f. triacantha (DC.) Schelle (1907), Mammillaria bernalensis Repp. (1987), Mammillaria brevispina Boed. (1928)(pro syn.), Mammillaria centralifera Repp. (1987), Mammillaria cirrhifera Mart. (1829), Mammillaria cirrhifera var. angulosior Lem. (1839), Mammillaria cirrhifera var. longiseta (Muehlenpf.) Salm-Dyck (1850), Mammillaria cirrifera Salm-Dyck (1850), Mammillaria compressa subsp. centralifera (Repp.) D.R.Hunt (1997), Mammillaria compressa var. rubrispina Borg (1937)(no Latin descr.), Mammillaria conopsea Van Houtte (1838), Mammillaria conopsea var. longispina Scheidw. (1839), Mammillaria esseriana Boed. (1928), Mammillaria kleinschmidtiana Zeiss, (1898), Mammillaria longiseta Muehlenpf. (1845), Mammillaria oettingenii Zeiss. (1898), Mammillaria plinthimorpha Jacobi (1856), Mammillaria squarrosa Meinsh. (1859), Mammillaria subangularis DC. (1828), Mammillaria subcirrhifera C.F.Först. (1846), Mammillaria tolimensis R.T.Craig (1945), Mammillaria tolimensis var. brevispina R.T.Craig (1945), Mammillaria tolimensis var. longispina R.T.Craig (1945), Mammillaria tolimensis var. subuncinata R.T.Craig (1945), Mammillaria triacantha DC. (1828), Neomammillaria compressa (DC.) Britton & Rose (1923), Neomammillaria subangularis (DC.) Y.Itô (1981)(without basionym ref.), Neomammillaria subangularis var. longiseta (Salm-Dyck) Y.Itô (1981)(not validly publ.), Neomammillaria subangularis var. rubrispina Y.Itô (1981)(not validly publ.), Neomammillaria tolimensis (R.T.Craig) Y.Itô (1981)(without basionym ref.), Neomammillaria tolimensis var. brevispina (R.T.Craig) Y.Itô (1981)(not validly publ.), Neomammillaria tolimensis var. longispina (R.T.Craig) Y.Itô (1981)(not validly publ.)

Mammillaria compressa DC. is the accepted scientific name for this species of cactus. It was named and described as such by Augustin Pyramus de Candolle in Mémoires du Museum d’Histoire Naturelle (Paris) in 1828.

Mammillaria bernalensis Repp., now a synonym, was named and described by Werner Reppenhagen in Gattung Mammillaria nach dem Heutigen Stand Meines Wissens in 1987 or 1989. I have seen both dates so I am not sure which is correct. He also named Mammillaria compressa f. bernalensis but the name isn’t on any database even as a synonym (not even in IPNI). 

The photo of Mammillaria compressa f. bernalensis on Llifle (Encyclopedia of Living Forms) looks like my plants… That name isn’t valid…

The genus, Mammillaria Haw., was named and described by Adrian Hardy Haworth in Synopsis Plantarum Succulentarum in 1812.

As of 12-7-23 when this page was last updated, Plants of the World Online by Kew lists 138 species in the Mammillaria genus (there were 154 the last time I updated). It is a member of the plant family Cactaceae with 150 genera. Those numbers could change as updates are made on POWO.

THERE ARE LINKS AND GROWING RECOMMENDATIONS AT THE BOTTOM OF THE PAGE FOR FURTHER READING.

I brought this pot of three cacti home from Walmart on 12-15-20. They had just got in a shipment of new cactus and succulents from Rocket Farms and they were still wrapped up in the shipping crate. The label on the pot just said “CACTUS” which was quite obvious. The plants all measured approximately 1 1/4″ tall x 1 1/2″ wide.

Since I bought this pot of three cactus unlabeled I had to do some research to find the name so I could accurately write about it. I did several things that led to some confusion and interesting conversation… After I took photos, I put them on the CactiGuide Forum for Cactus ID and a few Facebook Groups. Then did an online search for “long-tubercled cactus” and looked at Mammillaria photos on Llifle (Encyclopedia of Living Forms).

On the Llifle website, I found a photo that exactly matched my plants that was for Mammillaria compressa f. bernalensis. There were two problems. Mammillaria compressa f. bernalensis had also been named and described as Mammillaria bernalensis by Werner Reppenhagen in 1987-1989 which is a synonym of Mammillaria compressa… I will explain the issue in a bit.

Online, my plant matched photos associated with what is being called and sold as Mammillaria tlayecac… Apparently, the name stems from plants being sold by a nursery labeled Mammillaria sp. Rep or RO 831 Tlayecac. The name Mammillaria tlayecac flew across the internet at lightning-fast speed being sold online like it is a species name… 

HOWEVER… Rep. 831 Tlayecac represents observed or collected plants, whichever, by Mr. Werner Reppenhagen as Mammillaria multiseta. Rep. 831 is the observation number and Tlayecac is the location in Mexico where it was observed… Mammillaria multiseta has since then become a synonym of Mammillaria karwinskiana… I have an AWESOME Mammillaria karwinskiana and it is nothing like the plants I brought home… 

So, the name Mammillaria tlayecac is COMPLETELY incorrect and is not and never has been a valid species name. Some of the photos floating around online as M. tlayecac resemble the plants I brought home, and some don’t…

SO, let’s just ignore Rep. 831 for a minute because it obviously has nothing to do with my plants or yours for that matter. Mammillaria multiseta>Mammillaria karwinskiana is not the plants I brought home…

I think the plants I brought home were similar to the plants named and described as Mammillaria bernalensis by Werner Reppenhagen. He obviously knew the difference between the specimens he observed and Mammillaria compressa or he wouldn’t have given it a different name. When that species became a synonym of Mammillaria compressa, Werner Reppenhagen named Mammillaria compressa f. bernalensis, which must have not been validly published. To name a plant, rules have to be met. The name has to be validly published and described in “certain” types of publications. Anyway, apparently, the “infraspecific” name was not validly published because it isn’t listed as a synonym of Mammillaria compressa, but Mammillaria bernalensis was… Even so, Llifle and a few other websites, clearly say Mammillaria compressa f. bernalensis Repp.

If you read the description of Mammillaria compressa it will not match the plants I brought home because “they” are a variant (variety) of the species. SO, I have to use the descriptions provided for Mammillaria bernalensis/M. compressa f. bernalensis and NOT the species Mammillaria compressa… SO, the captions with the photos are labeled Mammillaria bernalensis (Syn. of M. compressa). I can’t use Mammillaria compressa f. bernalensis because it wasn’t a validly published name. That kind of screws things up a bit… Plants of the World Online lists 42 synonyms of Mammillaria compressa, some likely represents many variations of the species.

I acknowledge the fact that Mammillaria compressa is the accepted scientific name, but I think more clarification needs to be done on a variety/subspecies level.

Mammillaria compressa is a highly variable species found among many other species of cactus and succulent plants in and around Hidalgo, Queretaro, Guanajuato, Tamaulipas, Nuevo León, and San Luis Potosi in Mexico. Llifle mentions that there are/were 16 recognized subpopulations. The common name of the species is Mother of Hundreds apparently because it readily offsets to form large colonies. I read where the “variety” M. compressa subsp. centralifera does not offset as readily as the species but I don’t know about this one… Just have to wait and see what they do.

As I mentioned, I will use descriptions of the synonym Mammillaria bernalensis/M. compressa f. bernalensis because the pot of plants I brought home is a “variant” form of Mammillaria compressa and not the species…

Both the species and this “variant” have a kind of club-shaped to cylindrical growth habit. Information says the species can be bluish-gray while this variety is dark green. The size is somewhat different as well. Mammillaria compressa, according to information online, can grow to about 10″ tall x 4″ in diameter, and this variety grows from 2-8″ tall x 2-3″ or so in diameter. Time will tell…

The tubercles of both the species and this variety are very prominent, bluntly angled. pyramidal in shape, and closely set. Even though from areole to areola, on these plants, are fairly far apart. Comparing photos online of the species and this variety, the tubercles on my plants are larger, even though these youngsters are only 1 1/4″ wide x 1 1/2″ tall. In fact, I have 14 or so different Mammillaria species in my collection of cactus, and these have larger tubercles than any of them.

The areolas of the species, Mammillaria compressa,  produce 4-6 radial spines, usually from about 3/4 to 2 3/4″ (20-70 mm) long but can be smaller. The species also usually has no central spines, but apparently, there are exceptions. This variety produces 3-5 “small” radial spines and 1-3 central spines. Most of the radial spines are white with a brown tip and the central spines are white or brown. My plants have 4-5 radials and most areoles also have a central spine. Toward the bottom of the plants there appear to be no central spines or they are so small I can’t tell…

Mammillaria compressa also produces wool and bristles in the axils (the area between the tubercles). Many photos of Mammillaria compressa show plants with quite a lot of wool toward the plant’s apex. The only wool on the plants I brought home are only slight tufts on the tips of the areoles, and the apex is very small. Of course, my plants are very young and will no doubt change a lot as they grow… I have species that had very little wool when they were young that now are covered.

As you can see in the above photo, my plants are quite small when this photo was taken on December 12, 2020.

The above photo shows five brown-tipped white(ish) radial spines and one brownish central spine on the plants I brought home.

<<<<2021>>>>

The largest plant in the pot grew another 1/2″ taller and 1/4″ wider by August 17 in 2021. I may separate the three and put them in their own pots.

USEFUL INFORMATION:
Family: Cactaceae
Origin: Hidalgo, Queretaro, Guanajuato, Tamaulipas, Nuevo León and San Luis Potosi in Mexico
Zones: USDA Zones 9a-11 (20 to 40° F/-6.6 to 4.5° C)
Size: Up to 8-10” tall
Light: Sun to part shade.
Soil: Fast-draining. Good quality potting soil amended with pumice (50/50) or additional perlite and chicken grit (2-1-1).
Water: Regular watering during the growing season and barely, if any, during the winter

You can read my Cactus Talk & Update and Cactus & Succulent Tips to get my opinion about growing cacti and succulents.

When you bring your new plants home from the store, you need to check their roots and the soil to see if they are wet. If so, you may want to re-pot it right away. It is advisable to re-pot them in a better potting soil more suitable for cactus and succulents.

Unfortunately, all three of the plants in the pot died. Maybe I will run across this species again in the future.

I hope you enjoyed this page and maybe found it useful. I would like to hear from you if you have any comments, questions, or suggestions. Please click on “like” if you visited this page. It helps us bloggers stay motivated. 🙂 You can check out the links below for further reading. The links take you directly to the genus and species of this plant.

FOR FURTHER READING:
PLANTS OF THE WORLD ONLINE (GENUS/SPECIES)
WIKIPEDIA (GENUS/SPECIES)
LLIFLE (ENCYCLOPEDIA OF LIVING FORMS)
(M. compressa/M. compressa f. bernalensis)
DAVE’S GARDEN
CACTIGUIDE
MAMMILLARIAS.NET