Mammillaria longimamma

Mammillaria longimamma

Mammillaria longimamma DC.

A Mexican mammillaria with distinctly elongated, soft tubercles. In sections of the material studied, their interiors were filled with chlorenchyma, with a network of vascular bundles and a regular cell arrangement in the outer layer. The former name Dolichothele longimamma remains a synonym of the same species. [2-WWW] [Ozerova and Timonin 2020a]

2 min readUpdated 11 October 2026

Name and distribution

POWO accepts Mammillaria longimamma DC., with a natural range in northeastern Mexico extending to Veracruz. Dolichothele longimamma and Neomammillaria longimamma are homotypic synonyms, based on the same nomenclatural type. Its history of transfers between genera explains the different labels for this plant in older collections and descriptions. [2-WWW]

Long tubercles

In Ozerova and Timonin's anatomical comparison, tubercles of M. longimamma were the largest among the three species studied. They were up to 25 mm long and 8 mm in diameter, soft in consistency and shaped like rounded succulent leaves. The greenhouse material came from the Main Botanical Garden of the Russian Academy of Sciences in Moscow, and the voucher specimen bore the number Ozerova 20-4 in the MHA herbarium. [Ozerova and Timonin 2020a, pp. 11–12]

The tuberculate stem has an extensive surface, and each long tubercle contains a substantial volume of green tissue. In this material, chlorenchyma occurred around vascular bundles both in the cortex and the inner part. The authors found no distinct hydrenchyma. Water can remain in the large vacuoles of photosynthetic cells, so the absence of separate water-storage parenchyma does not mean that this organ has lost its succulence. [Ozerova and Timonin 2020a, pp. 12–16]

Kolumnowa organizacja chlorenchymy

Cells of the outer layer had similar dimensions in several directions and were arranged in oblique rows of four or five. The inner layer contained elongated cells with shorter-to-longer dimension ratios of about 1:2–1:3. Distinguishing these arrangements required longitudinal sections to supplement the cross-sectional view. This arrangement was shared by all three species studied, despite their differing tubercle sizes. [Ozerova and Timonin 2020a, pp. 12–14]

Spaces between the cell rows extend relatively straight into the tissue. The authors consider them pathways that facilitate CO₂ diffusion. They link this with large vacuoles, where malate is temporarily accumulated in CAM. This functional interpretation is based on anatomy. The experiment included neither direct gas-exchange measurements nor a comparison of the amount of water stored by individual species. [Ozerova and Timonin 2020a, pp. 14–16]

The tubercle as a photosynthetic organ. Mammillaria anatomy Cactus tubercles. Shape, arrangement and examples

Materials from the author's archive

The species also appears in Konrad Szychowski's private material archive. [Anonim b.d.z, file p. 1] [Kreuzinger 1935, file p. 9]

Synonyms and names in the literature

Dolichothele longimamma · Neomammillaria longimamma [2-WWW]

Sources for this account

[2-WWW]Source website

Plants of the World Online — Royal Botanic Gardens, Kew

https://powo.science.kew.org/

Accepted names, synonyms and distribution. A citation beside a taxon leads to its record.

Accessed 2026-10-08.

Article2020a

Cacti defeat physics: columnar chlorenchyma in tubercles of three species of Mammillaria Haw. (Cactaceae)

Ozerova L. V., Timonin A. C., Cacti defeat physics: columnar chlorenchyma in tubercles of three species of Mammillaria Haw. (Cactaceae), Wulfenia, 2020, 27:10-20

A comparison of tubercle anatomy in three Mammillaria species from greenhouse material, using transverse and longitudinal sections and light and scanning microscopy. The paper describes vascular bundles, the absence of a distinct hydrenchyma and the columnar arrangement of outer chlorenchyma cells. The discussion links this arrangement to gas diffusion, vacuole volume and CAM photosynthesis, and presents a hypothesis of its importance in the evolution of the succulent stem.

Physiology and anatomyGenusMammillaria

Article or source page ↗

Archived materialb.d.z

Tabela Dolichothele / Mammillaria

[Autor nieustalony, Tabela Dolichothele / Mammillaria, b.d.z]

A table from Konrad Szychowski's private archive presents Dolichothele and Mammillaria names. It preserves their connections in a historical treatment.

Genus

Bibliographic details and access scope

Data according to the source used. Author unknown. n.d. indicates that the publication date has not been confirmed.

Copy in the supplied material

Book1935

Verzeichnis amerikanischer und anderer Sukkulenten mit Revision der Systematik der Kakteen

[Kreuzinger K., Verzeichnis amerikanischer und anderer Sukkulenten mit Revision der Systematik der Kakteen, 1935]

The historical 1935 account contains a succulent list and a revision of cactus systematics. A copy is preserved in Konrad Szychowski's private archive.