Kalanchoe × trageri Gideon F.Sm., 2022

Smith, Gideon F., 2022, Kalanchoe × trageri, at last a name for K. blossfeldiana × K. pumila (Crassulaceae subfam. Kalanchooideae), a horticulturally successful nothospecies, Phytotaxa 550 (1), pp. 45-58 : 52-55

Kalanchoe × trageri Gideon F.Sm. , nothosp. nov.

( Figs 3–6 )

Type:— SOUTH AFRICA. Gauteng province —2528 (Pretoria): Pretoria , (– CA), ex hort., 15 November 2021, G . F . Smith 1165 (holotype PRU) .

Parentage:— Kalanchoe blossfeldiana Von Poellnitz (1934: 159) × Kalanchoe pumila Baker (1883: 139)

Diagnosis:—Plants of Kalanchoe ×trageri differ from the floury waxy K. pumila , one of its parents, by all plant parts being smooth and virtually non-waxy, as is found in K. blossfeldiana , the other parent. Leaf shape of K. × trageri is intermediate between that of K. blossfeldiana and K. pumila . The adaxial surfaces of the corolla lobes of K. blossfeldiana are crimson red and those of K. pumila variously light to dark pink and purple-veined, while those of K. × trageri are bright dark reddish purple. In K. × trageri the corolla lobes are distinctly recurved, as found in K. pumila , but not in K. blossfeldiana .

Description:—Perennial, usually sparsely-leaved, unbranched or few-branched, glabrous throughout, small to medium-sized, rounded to elongated succulent shrublets, 0.30–0.50(–0.75) m tall, including inflorescence. Stems green to reddish brown-infused when young, somewhat fleshy, later brown, somewhat corky, a few arising from near the base or higher up especially after flowering, erect to leaning, round to slightly angular-rounded in crosssection. Leaves opposite-decussate, petiolate, mid- to dark green, reddish-infused if grown in exposed positions, shiny, succulent, spreading to spreading-erect, horizontal to variously slightly flexed, papery on drying; petiole 10–15 mm long, distinctly channelled above, leaves not amplexicaul; blade 40–50(–65) × 30–35(–40) mm, ovate to ovate-oblong to somewhat obovate, slightly to distinctly channelled along midrib, veination indistinct; base cuneate; apex roundedobtuse; margins coarsely crenate or undulate-crenate with rounded, harmless teeth especially in upper ⅔ to ⅞ but not along cuneate base, rarely curved slightly downwards, sometimes reddish-infused. Inflorescence 150–300(–400) mm tall, erect to leaning, apically dense, many-flowered, ± flat-topped thyrse, branches opposite, erect, subtended by small, leaf-like bracts, lacking leafy branchlets in axils, axis light to yellowish green, sometimes reddish-infused; pedicels 2–4(–7) mm long, slender. Flowers erect, sometimes malformed with corolla lobes separating irregularly, 4-merous, rarely 3-, 5-, or 6-merous; calyx shiny reddish light green, strongly infused with small red spots especially towards tips and margins; sepals 5–7 mm long, fused for ± 0.25–0.50 mm, separate above, narrowly triangularlanceolate, acute-tipped, basally adnate for ± 0.5–1.0 mm, distinctly flared away from tube above, hardly contrasting against lower portion of corolla tube; corolla (10–)12(–14) mm long, very slightly enlarged lower down, not narrowing above carpels, not twisted apically after anthesis, tube 9–10 mm long, 4-angled, light greenish yellow lower down, transitioning to pinkish purple higher up, especially along angles, large-rounded to slightly box-shaped-square when viewed from below, remaining same diameter upwards, lobes (5–)7(–8) × (3.5–)4.0(–5) mm, adaxially uniformly bright dark reddish purple, ovate to oblong-ovate, rounded-acute at apex, mucronate or slightly notched. Stamens 8, inserted in two ranks, one at mid-tube, the other well above middle of tube, all four slightly exserted, two more so; filaments 2.5–3.0 mm long, thin, yellow; anthers 0.3–0.5 mm long, greenish yellow before anthesis, turning yellowish brown, very slightly exserted, visible at mouth, rounded to slightly elongated. Pistil consisting of 4 carpels; carpels 6–7 mm long, bright shiny light green; styles 2–3 mm long, red; stigmas capitate, whitish yellow, visible at mouth of corolla tube; scales 2.0– 2.5 mm long, linear, tapering to a very slightly capitate tip, light yellowish green. Follicles 5–7 mm long, straw-coloured to light brown at first, later brittle, grass spikelet-like, enveloped in dry, white to light brown remains of corolla, very weakly self-fertile. Seeds 0.25–0.40 mm long, dark brown, ± straight. Chromosome number: unknown. [Haploid and diploid chromosome numbers of parents: K. blossfeldiana , n = 17 (Friedmann 1971: 105) and 2 n = 34 (Baldwin 1938: 576, Sharma & Ghosh 1967: 318, Van Voorst & Arends 1982: 579, 580); and K. pumila , n = 18 (Friedmann 1971: 105) and 2 n = 36 (Friedmann 1971: 105) and 2 n = 40 ( Van Voorst & Arends 1982: 577, 580)].

Eponymy:— Kalanchoe × trageri is named for John Noyes Trager (born 19 August 1957, Buffalo, New York, USA –) ( Fig. 10 ), who is currently Curator of the Desert Collections at the Huntington Botanical Gardens in San Marino, California, USA, where he has been employed since 1983. Prior to that he worked with master propagator Frank Horwood at Abbey Garden Nursery when it was located in Carpinteria, Santa Barbara County. John holds a bachelor’s degree, awarded in 1992, in horticulture from California State Polytechnic University, Pomona, and earlier studied botany at the Santa Barbara City College and at the University of California, Santa Barbara. He has a longstanding interest in Kalanchoe and has seen to the introduction into horticulture of several Kalanchoe taxa through the annual International Succulent Introductions (ISI) programme offerings that he publishes in the Cactus and Succulent Journal ( US). Trager’s horticultural writings have appeared in numerous journals and he was a co-author of, and major contributor of images to, Dry climate gardening with succulents (Brown Folsom et al. 1995) that was collaboratively produced by the Huntington in 1995. John is a renowned photographer, with over 3 000 of his images having been published in numerous horticultural journals and books, including several works on the Aizoacae, as well as in books on the Anacampserotaceae , Asteraceae , Crassulaceae , and the multi-volume Illustrated Handbook of Succulent plants. John has travelled widely in search of plants and insects including in China, Costa Rica, Israel, Mexico, Namibia, South Africa, Thailand, and Venezuela.

Figures

FIGURE 3. A plant of Kalanchoe ×trageri. Note how the leaves are variously flexed from the horizontal, as is often found in K. pumila, one of its parents. Photograph: Gideon F. Smith.

FIGURE 4. Dense-flowered inflorescences of Kalanchoe ×trageri. Photograph: Gideon F. Smith.

FIGURE 5. The adaxial surfaces of the corolla lobes of Kalanchoe ×trageri are bright, dark reddish purple.The corolla lobes are ultimately strongly recurved, as in K. pumila. Photograph: Gideon F. Smith.

FIGURE 6. The aberrant flower of Kalanchoe ×trageri on the left is pentamerous, rather than tetramerous as in the case of the vast majority of Kalanchoe species. Note that the leaf crenations terminate in a sharper tip than in the case of K. blossfeldiana. Photograph: Gideon F. Smith.

FIGURE 10. John Noyes (John) Trager (1957–) after whom Kalanchoe ×trageri is named. Photograph: Daphne Trager.