Mammillaria is one of the largest genera in the cactus family (Cactaceae), with currently about 170 to 190 accepted species and around 99 subspecies. Most of the mammillarias are native to Mexico, while some come from the Southwestern United States, the Caribbean, Colombia, Guatemala, Honduras and Venezuela. The common name "pincushion cactus" refers to this genus and the closely related Escobaria.

The first species was described by Carl Linnaeus as Cactus mammillaris in 1753, deriving its name from the Latin mammilla, "nipple", referring to the tubercles that are among the distinctive features of the genus. Numerous species are commonly known as globe cactus, nipple cactus, birthday cake cactus, fishhook cactus or pincushion cactus (though such terms are also commonly used for related taxa, such as Escobaria or Ferocactus).

Description

The distinctive feature of the genus is the possession of an areole split into two clearly separated parts, one occurring at the apex of the tubercle, the other at its base. The apex part is spine-bearing, and the base part is always spineless, but usually bears some bristles or wool. The base part of the areole bears the flowers and fruits, and is a branching point. The apex part of the areole does not carry flowers, but in certain conditions can function as a branching point as well.

The plants are usually small, globose to elongated, the stems from in diameter and from tall, clearly tuberculate, solitary to clumping forming mounds of up to 100 heads and with radial symmetry. Tubercles can be conical, cylindrical, pyramidal or round. The roots are fibrous, fleshy or tuberous. The flowers are funnel-shaped and range from and more in length and in diameter, from white and greenish to yellow, pink and red in colour, often with a darker mid-stripe; the reddish hues are due to betalain pigments as usual for Caryophyllales. The fruit is berry-like, club-shaped or elongated, usually red but sometimes white, magenta, yellow or green. Some species have the fruit embedded into the plant body (cryptocarpic). The seeds are black or brown, ranging from in size. Many species exude a milky latex when injured.

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Mammillaria-flowers.jpg|alt=A color picture of a cactus with pink flower

Mammillaria spinosissma cv. un pico 20.JPG|Detail of cactus with fruit

Life cycle of Fish hook Cactus.jpg|Fish hook cactus (Mammillaria beneckei var. balsasoides)

</gallery>

Taxonomy

The genus Mammillaria in the family Cactaceae was proposed by Adrian Hardy Haworth in 1812. and conserved Mammillaria.

Mammillaria is a large and diverse genus with many species often exhibiting variations due to the nature of terrain, weather, soil and other ecological factors. As a result, subdivisions within the species has been rather inconsistent over time. Initially, some investigators were more inclined to consider each variation as a unique species, creating confusion and long synonymy-lists for some of the species.

Species

, Plants of the World Online accepted the following species:

  • Mammillaria albicoma <small>Boed.</small>
  • Mammillaria albiflora <small>(Werderm.) Backeb.</small>
  • Mammillaria albilanata <small>Backeb.</small>
  • Mammillaria anniana <small>Glass & R.A.Foster</small>
  • Mammillaria arreolae <small>P.Carrillo & Ortiz-Brunel</small>
  • Mammillaria aureilanata <small>Backeb.</small>
  • Mammillaria backebergiana <small>Franc.G.Buchenau</small>
  • Mammillaria baumii <small>Boed.</small>
  • Mammillaria beiselii <small>Diers</small>
  • Mammillaria beneckei <small>C.Ehrenb.</small>
  • Mammillaria bertholdii <small>Linzen</small>
  • Mammillaria bocasana <small>Poselg.</small>
  • Mammillaria bocensis <small>R.T.Craig</small>
  • Mammillaria boelderliana <small>Wohlschl.</small>
  • Mammillaria bombycina <small>Quehl</small> &ndash; silken pincushion
  • Mammillaria brandegeei <small>(J.M.Coult.) Engelm. ex K.Brandegee</small>
  • Mammillaria candida <small>Scheidw.</small>
  • Mammillaria carmeniae <small>Castañeda</small>
  • Mammillaria carnea <small>Zucc. ex Pfeiff.</small>
  • Mammillaria carretii <small>Rebut ex K.Schum.</small>
  • Mammillaria chionocephala <small>J.A.Purpus</small>
  • Mammillaria coahuilensis <small>(Boed.) Moran</small>
  • Mammillaria columbiana <small>Salm-Dyck</small>
  • Mammillaria compressa <small>DC.</small> &ndash; mother of hundreds
  • Mammillaria crinita <small>DC.</small> &ndash; rose pincushion cactus
  • Mammillaria crucigera <small>Mart.</small>
  • Mammillaria decipiens <small>Scheidw.</small>
  • Mammillaria deherdtiana <small>Farwig</small>
  • Mammillaria densispina <small>(J.M.Coult.) Orcutt</small>
  • Mammillaria discolor <small>Haw.</small>
  • Mammillaria dixanthocentron <small>Backeb. ex Mottram</small>
  • Mammillaria duoformis <small>R.T.Craig & E.Y.Dawson</small>
  • Mammillaria duwei <small>Rogoz. & P.J.Braun</small>
  • Mammillaria ekmanii <small>Werderm.</small>
  • Mammillaria elongata <small>DC.</small> &ndash; ladyfinger cactus
  • Mammillaria eriacantha <small>Link & Otto ex Pfeiff.</small>
  • Mammillaria erythrosperma <small>Boed.</small>
  • Mammillaria evermanniana <small>(Britton & Rose) Orcutt</small>
  • Mammillaria fittkaui <small>Glass & R.A.Foster</small>
  • Mammillaria flavicentra <small>Backeb. ex Mottram</small>
  • Mammillaria formosa <small>Galeotti ex Scheidw.</small>
  • Mammillaria × gajii <small>Chvastek & Halda</small>
  • Mammillaria gasseriana <small>Boed.</small>
  • Mammillaria geminispina <small>Haw.</small> &ndash; twin-spined cactus
  • Mammillaria gigantea <small>Hildm. ex K.Schum.</small>
  • Mammillaria glassii <small>R.A.Foster</small>
  • Mammillaria glochidiata <small>Mart.</small>
  • Mammillaria grusonii <small>Runge</small>
  • Mammillaria guerreronis <small>(Bravo) Boed.</small>
  • Mammillaria haageana <small>Pfeiff.</small>
  • Mammillaria hahniana <small>Werderm.</small> &ndash; old lady cactus
  • Mammillaria hernandezii <small>Glass & R.A.Foster</small>
  • Mammillaria herrerae <small>Werderm.</small>
  • Mammillaria heyderi <small>Muehlenpf.</small>
  • Mammillaria huitzilopochtli <small>D.R.Hunt</small>
  • Mammillaria humboldtii <small>C.Ehrenb.</small>
  • Mammillaria johnstonii <small>(Britton & Rose) Orcutt</small>
  • Mammillaria karwinskiana <small>Mart.</small> &ndash; royal cross mammillaria
  • Mammillaria klissingiana <small>Boed.</small>
  • Mammillaria knippeliana <small>Quehl</small>
  • Mammillaria kraehenbuehlii <small>(Krainz) Krainz</small>
  • Mammillaria lasiacantha <small>Engelm.</small> &ndash; golf-ball pincushion cactus
  • Mammillaria laui <small>D.R.Hunt</small>
  • Mammillaria lenta <small>K.Brandegee</small>
  • Mammillaria limonensis <small>Repp.</small>
  • Mammillaria linaresensis <small>R.Wolf & F.Wolf</small>
  • Mammillaria longiflora <small>(Britton & Rose) A.Berger</small>
  • Mammillaria longimamma <small>DC.</small> &ndash; finger cactus
  • Mammillaria luethyi <small>G.S.Hinton</small>
  • Mammillaria magnifica <small>Franc.G.Buchenau</small>
  • Mammillaria magnimamma <small>Haw.</small> &ndash; Mexican pincushion
  • Mammillaria mammillaris <small>(L.) H.Karst.</small>
  • Mammillaria manana <small>W.A.Fitz Maur. & B.Fitz Maur.</small>
  • Mammillaria marksiana <small>Krainz</small> &ndash; cabeza de viejo
  • Mammillaria mathildae <small>Kraehenb. & Krainz</small>
  • Mammillaria matudae <small>Bravo</small>
  • Mammillaria meiacantha <small>Engelm.</small>
  • Mammillaria melaleuca <small>Karw. ex Salm-Dyck</small>
  • Mammillaria melanocentra <small>Poselg.</small>
  • Mammillaria mercadensis <small>Patoni</small>
  • Mammillaria meyranii <small>Bravo</small>
  • Mammillaria microhelia <small>Werderm.</small>
  • Mammillaria moelleriana <small>Boed.</small>
  • Mammillaria monochrysacantha <small>Gonz.-Zam., D.Aquino & Dan.Sánchez</small>
  • Mammillaria morentiniana <small>Gonz.-Zam., D.Aquino, J.Mohl & Dan.Sánchez</small>
  • Mammillaria muehlenpfordtii <small>C.F.Först.</small>
  • Mammillaria multihamata <small>Boed.</small>
  • Mammillaria mystax <small>Mart.</small>
  • Mammillaria nana <small>Backeb.</small>
  • Mammillaria napina <small>J.A.Purpus</small>
  • Mammillaria nivosa <small>Link ex Pfeiff.</small> &ndash; woolly nipple cactus
  • Mammillaria nunezii <small>(Britton & Rose) Orcutt</small>
  • Mammillaria occulta <small>Zamudio & U.Guzmán</small>
  • Mammillaria orcuttii <small>Boed.</small>
  • Mammillaria oteroi <small>Glass & R.A.Foster</small>
  • Mammillaria painteri <small>Rose</small>
  • Mammillaria parkinsonii <small>C.Ehrenb.</small> &ndash; owl's eyes
  • Mammillaria pectinifera <small>F.A.C.Weber</small> &ndash; conchilinque
  • Mammillaria peninsularis <small>(Britton & Rose) Orcutt</small>
  • Mammillaria pennispinosa <small>Krainz</small>
  • Mammillaria perbella <small>Hildm. ex K.Schum.</small>
  • Mammillaria perezdelarosae <small>Bravo & Scheinvar</small>
  • Mammillaria petrophila <small>K.Brandegee</small>
  • Mammillaria petterssonii <small>Hildm.</small>
  • Mammillaria picta <small>Meinsh.</small>
  • Mammillaria pilispina <small>J.A.Purpus</small>
  • Mammillaria plumosa <small>F.A.C.Weber</small> &ndash; feather cactus
  • Mammillaria polyedra <small>Mart.</small>
  • Mammillaria polythele <small>Mart.</small>
  • Mammillaria pottsii <small>Scheer ex Salm-Dyck</small> &ndash; rattail cactus
  • Mammillaria pringlei <small>(J.M.Coult.) K.Brandegee</small>
  • Mammillaria prolifera <small>(Mill.) Haw.</small> &ndash; Texas nipple cactus
  • Mammillaria rekoi <small>(Britton & Rose) Vaupel</small>
  • Mammillaria rhodantha <small>Link & Otto</small> &ndash; rainbow pincushion
  • Mammillaria roseoalba <small>Boed.</small>
  • Mammillaria rzedowskiana <small>Zamudio & U.Guzmán</small>
  • Mammillaria sanchez-mejoradae <small>Rodr.González</small>
  • Mammillaria sartorii <small>J.A.Purpus</small>
  • Mammillaria scheinvariana <small>R.Ortega V. & Glass</small>
  • Mammillaria schiedeana <small>C.Ehrenb.</small>
  • Mammillaria schwarzii <small>Shurly</small>
  • Mammillaria scrippsiana <small>(Britton & Rose) Orcutt</small>
  • Mammillaria sempervivi <small>DC.</small>
  • Mammillaria senilis <small>Lodd. ex Salm-Dyck</small>
  • Mammillaria sinistrohamata <small>Boed.</small>
  • Mammillaria solisioides <small>Backeb.</small>
  • Mammillaria sonorensis <small>R.T.Craig</small>
  • Mammillaria sphacelata <small>Mart.</small>
  • Mammillaria sphaerica <small>A.Dietr.</small>
  • Mammillaria spinosissima <small>Lem.</small>
  • Mammillaria standleyi <small>(Britton & Rose) Orcutt</small>
  • Mammillaria supertexta <small>Mart. ex Pfeiff.</small>
  • Mammillaria surculosa <small>Boed.</small>
  • Mammillaria tayloriorum <small>Glass & R.A.Foster</small>
  • Mammillaria tepexicensis <small>J.Meyrán</small>
  • Mammillaria tonalensis <small>D.R.Hunt</small>
  • Mammillaria uncinata <small>Zucc. ex Pfeiff.</small>
  • Mammillaria varieaculeata <small>Franc.G.Buchenau</small>
  • Mammillaria vetula <small>Mart.</small>
  • Mammillaria voburnensis <small>Scheer</small>
  • Mammillaria wagneriana <small>Boed.</small>
  • Mammillaria weingartiana <small>Boed.</small>
  • Mammillaria wiesingeri <small>Boed.</small>
  • Mammillaria winterae <small>Boed.</small>
  • Mammillaria xaltianguensis <small>Sánchez-Mej.</small>
  • Mammillaria zeilmanniana <small>Boed.</small>
  • Mammillaria zephyranthoides <small>Scheidw.</small>
  • Mammillaria zublerae <small>Repp.</small>

Some former species

  • Mammillaria angelensis = Cochemiea angelensis
  • Mammillaria barbata = Cochemiea barbata
  • Mammillaria boolii = Cochemiea boolii
  • Mammillaria dioica = Cochemiea dioica
  • Mammillaria elegans = Mammillaria geminispina
  • Mammillaria fraileana = Cochemiea fraileana
  • Mammillaria goodridgei = Cochemiea goodridgei
  • Mammillaria grahamii = Cochemiea grahamii
  • Mammillaria guelzowiana = Cochemiea guelzowiana
  • Mammillaria mainiae = Cochemiea mainiae
  • Mammillaria marcosii = Mammillaria multihamata
  • Mammillaria microthele = Mammillaria formosa subsp. microthele
  • Mammillaria morganiana = Mammillaria parkinsonii
  • Mammillaria multidigitata = Cochemiea multidigitata
  • Mammillaria pondii = Cochemiea pondii
  • Mammillaria sheldonii = Cochemiea grahamii
  • Mammillaria tetrancistra = Cochemiea tetrancistra
  • Mammillaria thornberi = Cochemiea thornberi
  • Mammillaria wrightii = Cochemiea wrightii

<gallery widths="200px" heights="200px">

File:Pincushion_Cactus_Cluster_Sahuarita_Arizona_2013.jpg|Mammillaria cluster in Arizona.

File:Mammillaria bombycina11.JPG|Mammillaria bombycina

File:Mammillaria elongata 7.JPG|Mammillaria elongata

File:Mammillaria meicantha Engelm.PNG|Mammillaria meiacantha, photographed at Bedugul Botanical Garden, Bali, Indonesia

File:Mammillaria microhelia 11.JPG|Mammillaria microhelia

File:Mammillaria plumosa 3.JPG|Mammillaria plumosa

File:Mammillaria prolifera20100407 076.jpg|Mammillaria prolifera

File:Mammillaria (aka).jpg|Mammillaria spinosissima 'Un Pico'

File:Succu Mammillaria swinglei 01.jpg|Mammillaria sheldonii

File:Mammillaria_tetrancistra.JPG|Mammillaria tetrancistra

File:Mammillaria vetula sub. gracils.JPG|Mammillaria vetula

File:Mammillaria pectinifera 5.JPG|Mammillaria pectinifera

</gallery>

Distribution and habitat

Mammillarias are predominantly found in Mexico but also have a wide range of distribution in neighboring regions north of the equator including the southwest United States, the Caribbean, Guatemala and Honduras. The southernmost limits of its range appear to be Colombia and Venezuela, where only two known species are found. The fruit from several species is edible, sometimes described as delicious, and is best harvested when fully extruded from the axil and separates easily from the plant. while others are classified as Vulnerable (e.g., Mammillaria carretii) or Near Threatened (e.g., Mammillaria hahniana). A number of species are listed as Critically Endangered, including Mammillaria zeilmanniana and Mammillaria laui. The entire genus is listed in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), meaning that international trade is regulated to prevent unsustainable harvesting.