Glandulicactus mathssonii

Current name and earlier descriptions

Glandulicactus mathssonii is the name accepted in POWO. Ferocactus mathssonii and Glandulicactus crassihamatus remain its synonyms. Arias and Aquino's 2019 flora used the first of these former names. In Britton and Rose's 1922 monograph, the corresponding description appears under Ferocactus crassihamatus. A parenthetical explanation of the name allows the same taxon to be followed through publications from different periods. [2-WWW] [Arias and Aquino 2019] [Britton and Rose 1922]

Dry scrub of central Mexico

POWO gives the natural range as Guanajuato to San Luis Potosí. Flora del Bajío documents sites in northeastern Guanajuato, in the municipality of San Luis de la Paz, at elevations of 1800–2100 m. Plants occur in xerophilous scrub, a vegetation community adapted to periodic water shortages. In this part of the range, they flower in February and March, sometimes continuing into April. [2-WWW] [Arias and Aquino 2019, Arias and Aquino, pp. 101–102]

The older monograph also listed Querétaro. However, the authors of the 2019 regional revision noted the lack of later evidence confirming the species' presence in that state. Habitat loss through development and changes in land use was an important problem for populations in their study region. A historical locality record and current confirmation of a site therefore differ in documentary scope. [Arias and Aquino 2019, pp. 101–102]

Stem, areoles and spination

In the 2019 description, the stem is solitary, light green and spherical to shortly cylindrical. It reaches 10 cm in height and around 15 cm in diameter. Up to 13 ribs with rounded crests were distinguished, divided into prominent tubercles. The round areoles are 2.9–3.4 cm apart. A groove runs from the areole towards the tubercle base, with extrafloral nectaries near its lower end. [Arias and Aquino 2019, p. 99–100]

The flora's authors distinguished 4–6, occasionally 7 radial spines, up to 2.5 cm long. There were 6–7 central spines. Among these, they described three straight upper ones, three hooked lower ones and one projecting more prominently, up to 2.7 cm long. Young spines have brown and red shades, becoming grey with age. These numbers characterise the material used in the regional revision. [Arias and Aquino 2019, p. 99–100]

Britton and Rose gave eight radial and five central spines for F. crassihamatus. The difference involves both the counts and the assignment of individual spines to the two groups. Their arrangement, curvature, areole groove and flower features remain useful for identification. Basing a diagnosis on one counted ring of spines overlooks the variation visible in the descriptions. [Britton and Rose 1922, Britton and Rose, p. 144] [Arias and Aquino 2019, Britton and Rose, p. 144]

Flower, fruit and seed

The flowers described in the flora are 3–4 cm long and 2–3 cm wide. The outer tepals are dark brownish red. The inner ones are red, with a pale edge and ochre base. Red stamen filaments and style surround a yellow stigma divided into 8–10 parts. The colour pattern and organ positions complement vegetative features when identifying a flowering specimen. [Arias and Aquino 2019, p. 99–100]

The red fruit is spherical to ovoid, 1.5–2.5 cm long, with a partly succulent wall. The revision describes it opening at the base. The dark brown seeds are around 1.3 mm long. Once the fruit ripens, the seed material provides the starting point for sexual propagation, while germination rate and seedling requirements need data from experiments conducted on this taxon. [Arias and Aquino 2019, p. 100]

Materials from the author's archive

The species also appears in Konrad Szychowski's private material archive. [Kaktologia 2009b, file p. 9] [Neciu b.d., file p. 1]