ID cactus with small red flowers

[Widus]

Hi again,
Here is my other blooming cactus. Very faithful. Blooms every year for several weeks. What species is it?

[teo]

It's a Mammillaria sp. , not sure which one. I can see some hooked spines (but I don't think it's bombycina)

[Widus]

Thanks. I browsed through all the 171 Mammillaria species described on the dedicated page for the genus. Mammillaria nunezii, Mammillaria hutchisoniana, and Mammillaria duoformis have small pink flowers and hooked spines lime my cactus. Mammillaria nunezii appears the closest match to me. What do you think?

[teo]

If an unknown cactus is from a common source (like a garden centre) it is probably a common species so I would guess something more common than these.

[Widus]

According to the card on Mammillaria nunezii, it is mentioned that it is common worldwide. Anyways, Teo which species do you have in mind here?

[teo]

I just never had encountered nunezii. It might be it.

[jfabiao]

M. nunezii is a good bet.

[Widus]

Thanks for your comments. I will try to borrow the The Mammillaria Handbook, with descriptions, illustrations and key to the species from Robert Craig to try to confirm this identification.

[DaveW]

A more modern book on Mammillaria and in colour rather than the old monochrome Craig's Mammillaria book, now long out of date regarding newly discovered species, is "Mammillaria" by John Pilbeam (Cactus File Handbook). Maybe you can borrow that from a library. It's rather expensive secondhand now it is out of print, but don't mistake his earlier cheaper book of the same title for it, since The Cactus File Handbook series one is best.

http://www.cactus-mall.com/bookshop/mammillaria.html" onclick="window.open(this.href);return false;

Where the secondhand book dealers get their prices from I don't know, because most are well above the original cost new. Best place to look is on EBAY from time to time.

[Widus]

Thanks Dave. I'll try to borrow this one then.

[jfabiao]

I'll second Dave's recommendation. It's an excellent book.

[Widus]

I finally got this excellent John Pilbeam's book. It seems to confirm that my plant is M. nunezii subsp. nunezii. This plant is described as simple (my case) or clustering, globose to cyclindrical (my case), to 15 cm tall (mine 14 cm), 6-8 cm wide (mine 6.5 cm), 10 to 30 radial spines (22-23 in mine), central spines 2-4 (3-4 in mine), one sometimes hooked (almost always the case in mine), brown to nearly blackish at the tip (my case). Flowers are magenta (yes), about 2 cm long and 1.5 cm wide (currently my plant is not flowering but I would have said that the flowers on my plant are a bit smaller), narrow funnel-shaped (yes), flaring at the upper part (yes), the petals reflexing (yes). Fruits white tinged pink; seeds brown (never saw fruits on this plant; not pollinated despite being outside in summer?).

[DaveW]

Always remember plant descriptions are often based on a single original type specimen, or the group the original author observed and don't always represent all the variation of the population in habitat. Therefore allow a little latitude when comparing plants since measurements and spine numbers may not always match exactly. Plants don't always fit into "man made classification boxes".