Kalanchoe beauverdii var. pertinax Shtein & Gideon F.Sm., 2021

Shtein, Ronen & Smith, Gideon F., 2021, A revision of the climbing kalanchoes (Crassulaceae subfam. Kalanchooideae) of Madagascar including the description of Kalanchoe sect. Invasores and K. ser. Vilana, Phytotaxa 482 (2), pp. 93-120 : 105-114

1. Kalanchoe [subg. Bryophyllum ] sect. Invasores Shtein & Gideon F.Sm., sect. nov.

Type:— Kalanchoe tubiflora ( Harvey 1862: 380) Hamet (1912b: 44) (see Figueiredo & Smith 2017 on the nomenclature of K. tubiflora ).

Designations not validly published:—‘ Kalanchoe [sect. Bryophyllum ] subsect. Bulbilliferae ’ Boiteau (1947: 8), nom. inval. Under Turland et al. (2018: Art. 39.1) this designation was not validly published as it lacked a Latin description or diagnosis. Furthermore, Boiteau (1947) did not indicate which of the species he assigned to K. sect. Bryophyllum he included in ‘ K. [sect. Bryophyllum ] subsect. Bulbilliferae ’.

‘ Kalanchoe [sect. Bryophyllum ] subsect. Suffrutescentes ’ Boiteau (1947: 9), nom. inval. Under Turland et al. (2018: Art. 39.1) this designation was not validly published as it lacked a Latin description or diagnosis. Furthermore, Boiteau (1947) did not indicate which of the species he assigned to K. sect. Bryophyllum he included in ‘ K. [sect. Bryophyllum ] subsect. Suffrutescentes ’.

Diagnosis:—Taxa included in K. sect. Invasores differ from all other taxa included in Kalanchoe by a combination of characters, including being entirely glabrous (non-pruinose and -tomentose); by having simple or lobed leaves that are never compound, pinnate, or bipinnate; by having variously notched leaf margins; by being phyllo-bulbiliferous; by being non-flori- bulbiliferous until post-anthesis; by having non-acuminate petals; and by having scales that are less than twice as long as wide with upper corners that are not especially acute, and with the exception of K. rosei Raymond-Hamet & Perrier de la Bâthie (1914: 132) and K. peltigera Descoings (2005b: 6) , about as long as wide or shorter.

Description:—Perennial or biennial, erect, decumbent or climbing, entirely glabrous, non-pruinose, nontomentose, succulent plants. Leaves sessile to petiolate, simple to lobed but never pinnate, compound or bipinnate; petiole subcylindrical if present, not thinning or ornate towards the margins, sometimes amplexicaul, with marginal flanges not distinctly flatter than the rest of the petiole, nor ornate; blade symmetrical, subcylindrical-linear, lanceolate, ovate, oblong, or obovate; base amplexicaul if sessile or attenuate to peltate if petiolate; margins at least somewhat dentate, serrate, crenate, or subentire with few crenations, but never fully entire, marked by at least 2 pale organogenic and/or embryogenic spots, notches, or pedestals prior to bulbil production, bulbils proper, or abscission scars after bulbil detachment; apex acute to rounded; bulbil production induced to fully constitutive, and possible at each leaf marginal organogenic spot, notch, or pedestal, and between most crenations or serrations. Inflorescence not floribulbiliferous (i.e., producing dense clusters of bulbils) though may produce large and discrete bulbils post-anthesis, few-flowered cyme to dense corymbiform cymes or lax many-flowered paniculate cymes, small to large, leaning to drooping; peduncle erect to decurved to pendant; pedicels often relatively long, attenuated towards the flower or isodiametric throughout. Flowers pendent to omnidirectional if borne too densely to droop, glabrous, subtended by succulent, leaf-like bracts that persist for a short to long time, waxy bloom absent, papery when dry; calyx shorter than the corolla, consisting of 4 sepals fused for a significant length forming a tube, tube often as long or longer than free portion of sepals; sepals free portion lanceolate to ovate-triangular or deltoid, acute-tipped; corolla campanulate, flaring basally or basally and at the level of the ovaries, often stalked and constricted at level of ovaries; lobes drooping or spreading basally, obovate to ovate to somewhat subcircular, acute to rounded. Stamens 8, inserted low down in corolla tube, at ± just above lower level of carpels, included or exserted but always longer than corolla tube; filaments of two similar lengths, thin; anthers purplish black or yellow, not glandular, ovoid to hastate, often visible at least at the corolla mouth between corolla lobes. Pistil consisting of 4 carpels; carpels dark to dull green, ovate or oblong, widest basally or bulged in the middle; styles uniformly dull green, yellow or reddish; stigmas very slightly capitate, dark green; scales at most twice as long as wide, most often about as long as wide or shorter, free, incurved, somewhat variable, ± rectangular, trapezoidal, or semi-circular, thickened basally, tapering apically in thickness and width, upper corners subacute to rounded.

Included taxa:— K. daigremontiana , K. tubiflora , K. fedtschenkoi Raymond-Hamet & Perrier de la Bâthie (1915: 75) , K. ×houghtonii Ward (2006: 94), K. laetivirens Descoings (1997: 85) (treated as K. × laetivirens by Smith 2020c: 105), K. laxiflora Baker (1887: 472) , K. ×lokarana Descoings (2005a: 16), K. marnieriana H.Jacobsen ex L.Allorge in Boiteau & Allorge-Boiteau (1995: 102), K. × poincarei , K. peltigera , K. × rechingeri , K. ×richaudii Descoings (2005a: 14), K. rosei , K. sanctula Descoings (1997: 87) , K. serrata Mannoni & Boiteau (1947: 152) , K. tenuiflora Descoings (2004: 233) , K. waldheimii Raymond-Hamet & Perrier de la Bâthie (1915: 71) , and K. ser. Vilana (see below for a list of species included in K. ser. Vilana).

These taxa included in Kalanchoe [subg. Bryophyllum ] sect. Invasores are more closely related to K. tubiflora than to either K. pinnata var. calcicola Perrier de la Bâthie (1928: 21) or K. gastonis-bonnieri Hamet & Perrier de la Bathie (1912: 364) .

Distribution:— Madagascar. Some species and nothospecies are naturalised on all continents except Antarctica, predominantly in subtropical, tropical, and Mediterranean regions, from 20° to 40° northern and southern latitudes.

Etymology:—‘Invasores’, Latin for “invaders”, refers to the invasive tendencies of several representatives, and the ease with which all members can be grown in virtually any mild-climate region. All members reproduce readily through leaf bulbils, in some cases excessively so, or if induced to do so by leaves being severed; the most invasive do so constitutively ( Garcês et al. 2007, Herrando-Moraira et al. 2020). Of particular invasions concern are K. tubiflora , K. daigremontiana , K. laetivirens , and their hybrids, for example K. ×houghtonii, which has K. daigremontiana and K. tubiflora as parents.

Taxonomic notes:— Gehrig et al. (2001) recovered three main branches within their equivalent of K. subg. Bryophyllum . The first of the two, crown sister-branches is equivalent to the concept of Boiteau (1947: 9) for which they used the not validly published ‘ K. subsect. Proliferae ’. Note though that ‘ K. subsect. Proliferae ’ incorporates Bryophyllum calycinum , the type species of Bryophyllum , and by implication of K. subg. Bryophyllum , the rank used for it in this study, and K. sect. Bryophyllum . Even if validly published and typified on the included species K. prolifera (Bowie ex Hooker 1859: t. 5147) Hamet (1907: 19), it would still be a heterotypic synonym of K. subsect. Bryophyllum because of the close relationship between K. prolifera and K. pinnata , with B. calycinum being a synonym of the latter.

The second of the two crown branches contains the K. beauverdii species complex, as well as representatives of both ‘ K. subsect. Suffrutescentes ’ and ‘ K. subsect. Bulbilliferae ’ [see Boiteau (1947: 8–9), Boiteau & Allorge-Boiteau 1995: [16]], with the K. beauverdii complex occupying the basal-most position in this branch.

This relationship between the K. beauverdii species complex, ‘ K. subsect. Suffrutescentes ’, and ‘ K. subsect. Bulbilliferae ’ is also supported by morphological evidence—while the K. beauverdii species complex is highly specialised for climbing, they are allied with representatives of ‘ K. subsect. Suffrutescentes ’ and ‘ K. subsect. Bulbilliferae ’ based on nectar scale dimensions, calyx proportions, the lack of any waxy or floury external cover, and the lack of an indumentum. Moreover, like ‘ K. subsect. Proliferae ’, representatives of [ K. beauverdii + ‘ K. subsect. Suffrutescentes ’ + ‘ K. subsect. Bulbilliferae ’] are all capable of leaf bulbil production, but unlike most ‘ K. subsect. Proliferae ’, they do not form inflorescence bulbil clusters. For this reason, the K. beauverdii species complex, as well as representatives of ‘ K. subsect. Suffrutescentes ’ and ‘ K. subsect. Bulbilliferae ’, are here included in their own section, K. sect. Invasores. This section is sister to the autonymic K. [subg. Bryophyllum ] sect. Bryophyllum .

1a. Kalanchoe [subg. Bryophyllum sect. Invasores ] ser. Vilana Shtein & Gideon F.Sm., ser. nov.

Type:— Kalanchoe beauverdii Hamet (1907: 887) , as ‘ Beauverdi ’.

Designation not validly published:—‘ Kalanchoe [sect. Bryophyllum ] subsect. Scandentes ’ Boiteau (1947: 8), nom. inval, pro parte, excl. K. schizophylla . Under Turland et al. (2018: Art. 39.1), ‘ Kalanchoe subsect. Scandentes ’ was not validly published as it lacked a Latin description or diagnosis. Furthermore, Boiteau (1947) did not indicate which of the species he assigned to K. sect. Bryophyllum he included in ‘ K. [sect. Bryophyllum ] subsect. Scandentes ’.

Diagnosis:—Taxa included in K. ser. Vilana differ from all other taxa included in Kalanchoe that are phyllobulbiliferous by having basally woody, hard-wiry stems; by carrying single-spiked spinules, with the spinules formed between the petiole bases of each leaf pair; by the petiole being widened at the base, and often at least partially amplexicaul; by bulbil production being constitutive; by the corolla being funnelform-campanulate; and by the petals being at least as long as the corolla tube, usually longer.

Description:—Perennial, climbing, wiry-stemmed, entirely glabrous and non-pruinose, non-tomentose succulent plants. Stems basally woody, hard-wiry, thin, distinctly swollen and scarred at the internodes, carrying single-spiked spinules, with the spinules formed between the petiole bases of each leaf pair. Leaves widened at the base, at least partially amplexicaul, sessile to petiolate, simple to lobed but never pinnate, compound, or bipinnate, distinctly curved towards the stem at maturity with the apical portion more curved up to rolled to assist climbing; petiole subcylindrical if distinct, not thinning or ornate towards the margins, at least partially amplexicaul, with marginal flanges not distinctly flatter than the rest of the petiole, nor ornate; blade symmetrical, linear to oblong or ovate, sometimes cordate, sometimes trilobate-hastate; base amplexicaul if sessile or attenuate to peltate if petiolate; margins fully dentate to subentire with at least some minute teeth in the apical ⅓, but never fully entire, marked by at least 2 pale organogenic and/or embryogenic spotted notches prior to bulbil production, bulbils, or abscission scars after bulbil detachment; apex acute to obtuse; bulbil production constitutive. Inflorescence not flori-bulbiliferous, few-flowered cymes, relatively small, leaning to drooping; peduncle indistinct, decurved to pendant; pedicels isodiametric throughout. Flowers relatively large, pendent to omnidirectional if too dense to droop, glabrous, subtended by succulent, leaf-like bracts that persist for a long time, waxy bloom absent, papery when dry; calyx much shorter than the corolla, consisting of 4 sepals fused for a significant length, forming a tube, tube often as long as free sepals to much shorter; sepals free portion lanceolate to ovate-triangular, acute-tipped; corolla pale green, grey-green, brown, or bluish purple, funnelform-campanulate, flaring basally, not constricted elsewhere; lobes at least as long as the corolla tube, usually longer, spreading basally, often strongly, obovate to ovate to somewhat subcircular, acute to rounded. Stamens 8, inserted low down in corolla tube, at ± just above lower level of carpels, included or exerted but always longer than corolla tube; filaments of two similar lengths, thin; anthers purplish black, not glandular, ovoid to hastate, visible at least at the corolla mouth between corolla lobes. Pistil consisting of 4 carpels; carpels oblong, bulged in the middle, attenuate towards styles; styles uniformly dull green or reddish purple; stigmas very slightly capitate, dark green; scales shorter than wide, free, slightly incurved, somewhat variable, ± rectangular, thickened basally, tapering apically in thickness and width, upper corners slightly rounded, slightly tooth-like indented above.

Included species:— K. beauverdii , K. costantinii , K. guignardii , and K. scandens .

Distribution:—Central to southern Madagascar, south of Mahajanga. Xerophytic bush and dry woods on various soils.

Etymology:—‘Vilana’, meaning “twisted, crooked, evasive” in Malagasy, refers to the climbing growth habit of representatives of this group of species, with the stems and branches often twisting around objects for support. The name also references the seeds and bulbils that are small, brown, and hard to spot in the soil, so evading detection and dispersing in unexpected ways.

Taxonomic note:—The K. beauverdii species complex is here supported as a highly specialised, monophyletic, group based on several unique traits, the most obvious of which are: the presence of an internodal spinule, the flared corolla that is not constricted above the height of the carpels, the unique brown-purple flower colour, and the basally woody, wiry stems ( Figs 1 , 2 , 6 ). Traits such as the internodal spinule and the long, wiry stems, as well as the recurved leaf apices appear to be adaptations uniquely suited to their climbing habit. Recurved leaf apexes and wiry stems (however, herbaceous, not woody) are also present in K. schizophylla , a result of convergence, as shown above, whereas the internodal spinule is unique to this group. While K. schizophylla primarily uses its widened, amplexicaul petiole bases and back-facing, lateral leaflets that are apically recurved to straight, to hook onto objects for climbing ( Fig. 3 ), representatives of the K. beauverdii species complex mostly rely on their downwards recurved to rolled leaf apices and internodal spinules, with only one variety, K. beauverdii var. juelii , typically also using hook-like, lateral leaf blade lobes, though much fewer in number, for this purpose.

Boiteau & Mannoni (1949: 12) and Descoings (2003: 147) included K. costantinii , K. guignardii , K. juelii , and K. scandens in the synonymy of K. beauverdii , an interpretation with which we do not agree. With the exception of K. scandens , the geographical distribution ranges of these species are not known to overlap, and each species is morphologically consistent across large areas and habitats ( Fig. 7 ). Because of the disjunct distribution ranges of the species intermediate forms have thus far not been recorded. Furthermore, a wide range of leaf morphologies are represented in this species complex, as well as several different kinds of flowers, especially in terms of size, and calyx and petal morphology ( Table 3, Figs 1 , 2 , 4 , 6 ). Treating all these plants as representing a single species would constitute the under-recognition of diversity, and result in a species with eight varieties. Such a conglomeration of varieties also complicates addressing the relationships among them.

B. Kalanchoe beauverdii Hamet (1907: 887) , as ‘ Beauverdi ’

Homotypic synonym:— Bryophyllum beauverdii (Hamet) Berger (1930: 412) . Type :— MADAGASCAR. Southern region, [M.F.] Geay 6313, dans les collections de la chaire de culture du Muséum [not available online] (syntype, P); [M.F.] Geay 6352, dans les collections de la chaire de culture du Muséum (syntype, P P-P00374190! [Image available at http://coldb.mnhn.fr/catalognumber/ mnhn/p/p00374190]). Of the two syntypes, M.F. Geay 6352 (P), which is available online, is here designated as lectotype.

Epitype:— MADAGASCAR. Androy region, southern Madagascar, Cape Sainte Marie, collected by P. Richaud s.n., 1994, R. Shtein 391, [TELA913] (epitype, TELA!), here designated.

Designation not validly published:—The designation ‘ K. beauverdii var. typica ’ Boiteau & Mannoni (1949: 13) was not validly published ( Turland et al. 2018: Art. 24.3).

Description:—Perennial, climbing, diffusely shrub-like, much-branched, glabrous, fragile succulent, of variable height depending on plants with which it grows and that provide support for the scandent stems and branches. Stem and branches very thin, <3 mm in diameter, growing upwards or sideways, climbing and twining into and leaning on surrounding plants, or variously dangling, mid- to light green to reddish brown at first, later whitish grey, herbaceoussucculent at first, becoming hard-wiry below; internodes distinctly swollen, scarred and minutely spinulescent. Leaves distinctly curved towards the stem at maturity with the apical portion curved in slightly more to assist climbing, smooth, succulent, consistently petiolate, ± channelled above along midrib, convex below, uniformly light green, rarely very slightly brownish purple-infused towards apex, shiny, lacking a waxy bloom, opposing leaves not connate, contact obstructed by a single internodal spike on either side; petiole (7–)10–20(–37) mm, grooved above, succulent, prominent, gradually widening to the base, partially amplexicaul, reaching the spinule; blade 10–33 × 5–23 mm at maturity, slightly wider than long to considerably longer than wide, ovate to ovate-cordate to ovate-oblong to trilobatehastate, ± triangular in outline, succulent; base cuneate to auriculate-haste to auriculate-peltate, rounded on the lower angles; margins irregularly dentate in the apical ⅓ to fully dentate; apex acute or bluntly acute, with 1–12 easily caducous bulbils; bulbil production constitutive. Inflorescence a terminal, 1- to 3-flowered cyme, comparatively small, leaning to drooping; peduncle indistinct, often decurved, light green; pedicels 6–30 mm long, light green, glabrous. Flowers 3–5(–7) in a cyme, pendent, glabrous, subtended by succulent, leaf-like bracts that persist for a long time, dull creamy green, densely infused with evenly distributed purple spots and veins arranged in a longitudinal network, waxy bloom absent, papery when dry; calyx consisting of 4 sepals, tube comparatively short, sometimes slightly constricted medially, shiny light green, very faintly infused with minute purple spots especially basally and apically, purple arranged in faint longitudinal lines, basally rounded; sepals 13.5–22.0 mm long, 7–10 mm across where fused, free portion lanceolate-triangular, fused for ± 6–10 mm, acute-tipped, obscuring ± ½ of the corolla tube; corolla 35–50 mm long; tube 8–25 mm long, cylindrical-campanulate, strongly flared towards the mouth; lobes 10–25 × 14.5–22.0 mm, obovate to ovate to somewhat subcircular, tapering apically, obtuse to rounded-obtuse, mucronate or non-mucronate. Stamens 8, inserted low down in corolla tube, at ± just above lower level of carpels, all included but visible at the mouth; filaments of two lengths, ± 18–25 mm long, thin, light green, obscurely purplish red infused lower down; anthers ± 1.0– 1.5 mm long, purplish black, ovoid to hastate, visible at the corolla mouth. Pistil consisting of 4 carpels; carpels ± 6–7 mm long, uniformly shiny light green, oblong, bulged in the middle, attenuate towards styles; styles 14.8–20.0 mm long, light green, very slightly purplish-infused; stigmas very slightly capitate, dark green; scales 1–2 × 1.50–2.25 mm, free, somewhat variable, ± horizontally rectangular, more rarely square, tapering upwards, upper corners slightly rounded, slightly tooth-like indented above. Follicles not seen. Seeds not seen. Chromosome number: 2 n = 34 ( Friedmann 1971: 104).

Distribution:—Androy and south Atsimo-Andrefana regions, the southernmost part of Madagascar ( Fig. 7 ).

Ba. Kalanchoe beauverdii var. beauverdii

Description:— Petiole 7–15 mm long; blade (15–)20–25 × (10–) 15–18 mm at maturity, longer than wide, ovate to ovate-oblong; base cuneate to auriculate to rarely somewhat hastate; margins dentate along apical ⅓ only, with 2–6 easily caducous bulbils; pedicels 6–8 mm long; calyx tube slightly constricted medially; sepals 17–20 mm long, 9–10 mm across where fused, fused for ± 6.5–7.0 mm; corolla 35–45 mm long; tube 14–16 mm long; lobes ± 16–25 × 17–22 mm, apically obtuse, non-mucronate; filaments ± 20–25 mm; styles ± 15–17 mm long; scales ± 1.75–2.00 × 2.25–2.50 mm.

Distribution:—Androy region, southernmost Madagascar ( Fig. 7 ).

Bb. Kalanchoe beauverdii var. juelii (Raymond-Hamet & Perrier de la Bâthie 1914: 135) Smith & Figueiredo (2019: 119)

Basionym:— Kalanchoe juelii Raymond-Hamet & Perrier de la Bâthie (1914: 135) , as ‘ Jueli ’; Homotypic synonym:— Bryophyllum juelii (Raym.-Hamet & H.Perrier) Berger (1930: 411). Type:— MADAGASCAR. Sands and dunes of the Lower Menerandra and the Mahafaly coast, June 1910, (‘Dunes et endroits sablonneux, Bas Menerandra et côte Mahafaly’) [J.M.H.A.] Perrier de la Bâthie 10.088 (lectotype, P P00431147![Image available at http://coldb.mnhn.fr/catalognumber/mnhn/p/p00431147]). Lectotype designated by Smith & Figueiredo (2019: 119).

Designation not validly published:—‘ Kalanchoe beauverdii var. juelii ’ (Raym.-Hamet & H.Perrier) Rauh & Hebding in Rauh (1995a: 15), nom. inval. ( Turland et al. 2018: Art. 41.5).

Description:— Petiole 8.7–37.0 mm long; blade 10–33 × 5–23 mm at maturity, longer than wide, ovate, trilobatehastate; base cuneate to auriculate-hastate; margins irregularly dentate for up to the full length, with 2–12 easily caducous bulbils; pedicels 12–18 mm long; calyx tube unconstricted medially; sepals 13.5–16.0 mm long, 7–9 mm across where fused, fused for ± 8.5–10.0 mm; corolla 35–40 mm long, 70–80 mm wide; tube (8.0–)11.0– 12.3 mm long; lobes ± (10–)15–16 × 14.5–16.5 mm, apically rounded-obtuse, mucronate; filaments ± 18–20 mm; styles ± 14.8– 15.4 mm long; scales ± 1.3–1.4 × 2.10–2.25 mm.

Distribution:—Around Androka, southwestern Madagascar. South Atsimo-Andrefana region ( Fig. 7 ).

Additional material examined:—P-P00431143; P-P00431153.

Bc. Kalanchoe beauverdii var. pertinax Shtein & Gideon F.Sm. , var. nov.

Type:— SOUTH AFRICA. Gauteng Province. Pretoria. 2528 (– CB), ex hort., G . F . Smith 1126 (holotype, PRU!) .

Diagnosis:—Differs from K. beauverdii var. beauverdii by the leaf blade being ovate-cordate; by the leaf base being auriculate-peltate; by the margins up to fully dentate; and by the free corolla lobes being mucronate. Differs from K. beauverdii var. juelii by the leaf blade being ovate-cordate; by the leaf base being auriculate-peltate; by the calyx tube being basally rounded and slightly constricted mid-length, over 2× shorter than the free sepal segments; and by the petals being apically obtuse.

Description:— Petiole (7–)10–20(–22) mm long; blade (10–)12–15 × (10–) 16–20 mm at maturity, slightly wider than long, generally ovate-cordate to ± triangular in outline; base auriculate-peltate, rounded on the lower angles; margins irregularly dentate for up to the full length, with 1–2(–3) easily caducous bulbils; pedicels (15–)25(–30) mm long; calyx tube slightly constricted medially; sepals 18–22 mm long, 9–10 mm across where fused, fused for ± 6–8 mm; corolla 40–50 mm long; tube 20–25 mm long; lobes ± 22–24 × 16–17 mm, apically obtuse, mucronate; filaments ± 22–25 mm; styles ± 18–20 mm long; scales ± 1.0–1.5 × 1.5–2.0 mm.

Flowering time:—August to September(–October), i.e., late-winter to early-summer (southern hemisphere).

Distribution:—The natural geographical distribution range of K. beauverdii var. pertinax is uncertain. Since K. beauverdii , as interpreted here, is endemic to southernmost Madagascar, in the Androy or south Atsimo-Andrefana regions, we postulate that this is also the most likely natural habitat of K. beauverdii var. pertinax . Based on its size and scrambling habit that are consistent with those of K. beauverdii ; its flowers that are almost indistinguishable from those of K. beauverdii var. beauverdii ; and the single-spike spinulescent stems that is found exclusively in all the representatives of K. ser. Vilana, but which is absent in inter-section and -series hybrids (for example K. × rechingeri and K. × poincarei ; see Fig. 5 and discussion below) or is present as a broader, rectangular wedge rather than a spinule, we do not regard K. beauverdii var. pertinax as being of hybrid origin. The flowers of K. beauverdii var. pertinax are among the largest in this species complex only rivalled by those of K. beauverdii var. beauverdii ( Figs 2 , 6 ), and the leaves are strongly petiolate and lack any similarities exclusive to other species that we recognise in K. ser. Vilana. Therefore, there is no evidence to suggest that K. beauverdii var. pertinax is an intra-series hybrid.

Etymology:—The varietal epithet ‘pertinax’ is derived from Latin, meaning “tenacious, persevering, stubborn”, in reference to material having eluded description until now, and doubt about its uncertain geographical distribution (see above).

C. Kalanchoe costantinii Hamet (1907: 889) , as ‘ Costantini ’

Homotypic synonym:— Bryophyllum costantinii (Raym.-Hamet) Berger (1930: 412). Type:— MADAGASCAR. Fort Dauphin region , [ M. F.] Geay 6421, dans les collections de la chaire de culture du Muséum ( P, not extant) .

Neotype:— MADAGASCAR. Fort Dauphin region , Ambatoabo , Ankoba, 2 km northeast of Imonty dry forest, 20 July 2011, also labelled “Missouri Botanical Garden Herbarium ( MO)”, 250 m asl, F. Ratovoson 1611 (neotype, P P-P01045912! [Image available at http:// coldb.mnhn.fr/catalognumber/mnhn/p/p01045912]), here designated.

Nomenclatural notes:—Under K. beauverdii, Boiteau & Mannoni (1949: 13) proposed the recognition of taxa to which they applied the designation ‘ Kalanchoe beauverdii var. typica ’ Boiteau & Mannoni (1949: 13). The concepts to which this designation was applied by Boiteau & Mannoni (1949) are here included pro parte in K. costantinii .

The type of the name K. costantinii, Geay 6421, is not extant at Herb. P nor at Herb. MPU. In the absence of other original material associated with the name we here designate a neotype, F. Ratovoson 1611 (P).

Description:—Perennial, climbing, diffusely shrub-like, much-branched, glabrous, fragile succulent, of variable height depending on plants with which it grows and that provide support for the scandent stems and branches. Stem and branches relatively thick, up to ± 5 mm in diameter, growing upwards or sideways, climbing and twining into and leaning on surrounding plants, or variously dangling, mid- to light green to bluish grey at first, later dull midbrown, herbaceous-succulent at first, becoming hard-wiry below; internodes distinctly swollen, scarred and minutely spinulescent. Leaves ± flat, concave or convex, basally distinctly bent towards the stem, at maturity with the apical portion curved in slightly to assist climbing, smooth, succulent, sessile or rarely very slightly subsessile, indistinctly channelled above along midrib, uniformly light green at maturity, mid-brown or bluish grey strictly apically, shiny, lacking a waxy bloom; petiole mostly absent; blade (20–)30–50 × (10–) 20–30 mm at maturity, as long as wide to longer than wide, generally ovate-oblong to suborbicular in outline, very succulent; base fully amplexicaul, growing over a single internodal spikelet on either side, opposing leaves connate; margins irregularly dentate for up to ± ½ length or less, dentation larger towards apex; apex subacute to obtuse, with 2–4(–6) easily caducous bulbils; bulbil production constitutive, ranging from frequent to comparatively infrequent. Inflorescence 1–3 terminal, 3- to 7-flowered cyme, comparatively small, leaning to drooping; peduncle indistinct, decurved to pendant, dull green-grey to brownish-green; pedicels (5–)10(–16) mm long, dull green-grey to green-brown, glabrous. Flowers pendent to omnidirectional, glabrous, subtended by succulent, leaf-like bracts that persist for a long time, grey, densely infused with evenly distributed brown to bluish purple spots and veins arranged in a longitudinal network, brown or blue-purple towards and at free petal segments, waxy bloom absent, papery when dry; calyx uniformly light green, consisting of 4 sepals, tube convex or concave, ± as wide as long or much wider than long, 7–15 mm across where widest, rounded to slightly 4-angled to strongly 4-angled, basally rounded, or indented-rounded above each free sepal segment; sepals 16–20 mm long, 7–15 mm across where fused, free portion ovate-triangular, fused for ± 7–9 mm, strongly incurved, acute-tipped, obscuring> ½ of the corolla tube; corolla 25–27 mm long; tube 9–12 mm long, cylindrical-campanulate, strongly flared towards the mouth; lobes ± 13–18 × 10–13 mm, slightly to distinctly spreading basally, medially strongly incurved or apically straight to recurved, obovate to ovate to somewhat subcircular, tapering apically, acute, mucronate. Stamens 8, inserted low down in corolla tube, at ± just above lower level of carpels, all included but visible at the mouth; filaments of two lengths, ± 18–21 mm long, thin, dull green, strongly infused with bluish purple except basally and apically; anthers ± 1.0– 1.5 mm long, purplish black, ovoid to hastate, visible at the corolla mouth between corolla lobes. Pistil consisting of 4 carpels; carpels ± 6–7 mm long, uniformly shiny green, oblong, bulged in the middle, attenuate towards styles; styles ± 11–15 mm long, uniformly dull green; stigmas very slightly capitate, dark green; scales ± 1.5–2.0 × 2.0– 2.5 mm, yellow green, free, somewhat variable, ± horizontally rectangular, wider than long, thickened basally, tapering apically in thickness and width, upper corners slightly rounded, slightly tooth-like indented above. Follicles not seen. Seeds not seen. Chromosome number unknown.

Distribution:—Eastern to southeastern Madagascar. Currently known from the Anosy and Atsinanana regions ( Fig. 7 ).

Additional material examined: — MADAGASCAR. Berenty region, 1994, P. Richaud s.n. R. Shtein 901 [TELA914]; P-P00431142; P-P00431154; P-P00431170; P-P00431158; P-P00431161; P-P00431171; P-P00431172; P-P00431174; P-P00431175; P-P00438089; P-P00209572; P-P00438090; P-P00438092; P-P00438091; P-P00431176; P-P00431179 to P-P00431183; P-P00431184.

Ca. K. costantinii var. costantinii

Description:— Leaf distinctly longer than wide, ovate-oblong in outline; bulbil production frequent; calyx tube convex, ± as wide as long, 7.0– 8.5 mm across where widest, rounded to slightly 4-angled, not indented above each free sepal segment, basally rounded; corolla brown towards and at free petal segments; tube 11–12 mm long; lobes ± 13–14 × 10.0– 11.5 mm, at least slightly spreading, apically straight to recurved; styles ± 14–15 mm long.

Distribution:—Eastern to southeastern Madagascar. Currently known from the Anosy and Atsinanana regions.

Cb. Kalanchoe costantinii var. unguifera Shtein & Gideon F.Sm. , var. nov.

Type:— MADAGASCAR. Toliara province (now the Anosy region), Préfecture de Fort-Dauphin [now Tôlañaro, alternatively spelled ‘Tolagnaro’], forêt sèche de Vinanibe, 17 October 1990, 100 m asl, N. Dumetz 1302 (holotype, P P-P00431159! [Image available at http://coldb.mnhn.fr/catalognumber/mnhn/p/p00431159]) .

Diagnosis:—Differs from K. costantinii var. costantinii by its leaves being thicker and shorter, usually about as long as wide, more ovate-suborbicular than ovate-oblong; by its calyx tube being concave, much wider than long, strongly 4-angled, and indented above each free sepal segment; by its petals and sepals being incurved; and by its corolla being blue-purple towards and at the petals.

Description:— Leaf at least about half as wide as long to as wide as long, generally abruptly ovate to suborbicular in outline; bulbil production relatively infrequent; calyx tube concave, much wider than long, 12–15 mm across where widest, strongly 4-angled, indented above each free sepal segment, basally indented-rounded; corolla distinctly bluepurple towards and at free petal segments; tube 9–10 mm long; lobes ± 15–18 × 12–13 mm, spreading basally, medially strongly incurved; styles ± 11–13 mm long.

Flowering time:—Late February to April (northern hemisphere), i.e., late-winter to early-spring.

Distribution:—In proximity to the coastlines around Tôlañaro, southern Androy region, southeastern Madagascar ( Fig. 7 ).

Additional material examined:— MADAGASCAR. Tôlañaro region, 1994, collected by P. Richaud s.n., R. Shtein 957 [TELA906, TELA915]; P-P00431151; P-P00431165; P-P00431160; P-P00431166; P-P00431173.

Etymology:—The varietal epithet is derived from the Latin ‘unguis’ meaning “nail, claw”, and feminine ‘-fera’ meaning “to bear, to carry”, to denote the uniquely incurved petals and sepals, and indented calyx that all have a clawlike appearance.

D. Kalanchoe guignardii Hamet & Perrier de la Bâthie (1912: 368) , as ‘ Guignardi ’

Homotypic synonym:— Kalanchoe beauverdii var. guignardii (Raym.-Hamet & H.Perrier) Boiteau & Mannoni (1949: 13), as “ Var. Guignardi R. Hamet pro. sp.” ( Turland et al. 2018: Articles 38.14, 41.3, and 41.4). Type:— MADAGASCAR. Mahajanga Province, west of Manongarivo (Ambongo), very dry sandy woods, January 1905, [ J. M.] H.[ A.] Perrier de la Bâthie 1804 (letotype, P P- P00431148 ! [Image available at http://coldb.mnhn.fr/catalognumber/mnhn/p/p00431148]), here designated .

Notes on the type:—In the protologue of the name Kalanchoe guignardii, Hamet & Perrier de la Bâthie (1912: 368) states the following only: “Cette plante, qui porte le nom de M. Guignard, member de l’Institut et Directeur honoraire de l’Ecole supérieure de Pharmacie, a été récoltée par M. Perrier de la Bâthie, en janvier 1905, dans les bois sablonneux très secs de Manongarivo.” [English: “This plant, which bears the name of M. Guignard, member of the Institute and Honorary Director of the Higher School of Pharmacy, was collected by Mr Perrier de la Bâthie, in January 1905, in the very dry sandy woods of Manongarivo.”]. No specimens are therefore explicitly mentioned. However, the specimen, MNHN-P-P00431148, here designated as lectotype, was indeed collected by Perrier de la Bâthie in January 1905 west of Manongarivo, the location mentioned in the protologue of the name K. guignardii , and would qualify as original material in the sense of Turland et al. (2018: Art. 9.4) as it was clearly available to the authors prior to publication of the protologue in 1912. Perrier de la Bâthie donated the specimen to Herb. P in 1932 after presumably at first keeping it in his personal herbarium.

Description:—Perennial, climbing, diffusely shrub-like, much-branched, glabrous, fragile succulent, of variable height depending on plants with which it grows and that provide support for the scandent stems and branches. Stem and branches thin, up to ± 3.25 mm in diameter, growing upwards or sideways, climbing and twining into and leaning on surrounding plants, or variously dangling, grey-green to brown to reddish brown, herbaceous-succulent at first, becoming hard-wiry below; internodes distinctly swollen, scarred and minutely spinulescent. Leaves distinctly curved towards the stem at maturity with the apical portion curved in slightly more to assist climbing, smooth, succulent, sessile to subsessile, strongly channelled above along midrib, convex below, uniformly reddish brown or dark brown at maturity, or reddish brown towards the margins and apex and green along the midrib when young, shiny, lacking a waxy bloom, opposing leaves not connate, contact obstructed by a single internodal spike on either side; petiole largely indistinct from blade when present, ± ⅓ of leaf in length, grooved above, succulent, partially amplexicaul, clasping the stem, reaching the internodal spike; blade 45–60(–70) × (3–)5–10(–35) mm at maturity, much longer than wide, generally ovate-oblong to linear in outline, succulent; base attenuate if subsessile or partially amplexicaul if sessile; margins irregularly indistinctly dentate for up to ± ⅓ of their length, generally less; apex acute, with 2–4(–8) easily caducous bulbils; bulbil production constitutive. Inflorescence a terminal, 5- to 13-flowered cyme, comparatively small, leaning to drooping; peduncle indistinct, decurved to pendant, reddish grey-brown; pedicels (5–)10–20(–30) mm long, grey-brown to reddish brown, glabrous. Flowers pendent, glabrous, subtended by succulent, shorter, leaflike bracts that persist for a long time, grey, densely infused with evenly distributed dark reddish brown spots and veins arranged in a longitudinal network, waxy bloom absent, papery when dry; calyx adpressed to corolla tube, consisting of 4 sepals, tube short, round to slightly 4-angled, brown-green to grey-brown, strongly infused with dark reddish brown interconnected patterns, spots and longitudinal lines, basally rounded; sepals 10.5–16.0 mm long, 4.5–11.0 mm across where fused, free portion lanceolate-triangular, fused for ± 1.6–4.0 mm, acute-tipped, obscuring <⅓ of the corolla tube; corolla 17–24 mm long; tube 8–10 mm long, cylindrical-campanulate to almost tubular, slightly narrowed or flared towards the mouth; lobes ± 9–14 × 4.6–9.0 mm, narrowly obovate to oblong, tongue-shaped, gradually and slightly widening up to ⅔ of length then tapering apically, obtuse to somewhat rounded, mucronate. Stamens 8, inserted low down in corolla tube, at ± just above lower level of carpels, exerted for ± 3–7 mm; filaments of two lengths, ± 18–22 mm long, thin, dull grey, strongly infused with purplish red except basally and apically; anthers ± 1.0– 1.5 mm long, purplish black, ovoid to hastate, completely exerted. Pistil consisting of 4 carpels; carpels ± 5–6 mm long, shiny grey-green, strongly infused with purplish red spots basally and more so apically, oblong, bulged in the middle, attenuate towards styles; styles ± 14 or 19–21 mm long, grey-green, strongly purplish red-infused; stigmas very slightly capitate, dark green; scales 0.6–0.7 × 1.10–1.25 mm or 1.5–2.0 × 2.0– 2.5 mm, yellow-green, free, somewhat variable, ± horizontally rectangular, thickened basally, tapering apically in thickness and width, upper corners slightly rounded, slightly tooth-like indented above. Follicles not seen. Seeds not seen. Chromosome number unknown.

Distribution:—Western to southwestern Madagascar. Currently known from the Boeny and Atsimo-Andrefana regions ( Fig. 7 ).

Da. Kalanchoe guignardii var. guignardii

Description:— Leaf blade up to ±65 × 8.5–35.0 mm at maturity; calyx tube and free sepal segments spreading; sepals 10.5–13.0 mm long, 4.5–7.0 mm across where fused, fused for ± 1.6–2.4 mm; corolla 20–24 mm long; tube almost tubular, slightly narrowed towards the mouth; lobes ± 11.25–14.00 × 4.6–5.0 mm, apically acute; carpels distinctly divergent at seed maturity; styles ± 14 mm long; scales ± 0.6–0.7 × 1.10–1.25mm.

Distribution:—Around Manongarivo, Boeny region, western Madagascar ( Fig. 7 ).

Db. Kalanchoe guignardii var. schistosepala Shtein & Gideon F.Sm. , var. nov.

Type:— MADAGASCAR. Ifaty region , 1994, collected by P . Richaud s.n. R . Shtein 212 [ TELA907 ] (holotype, TELA!); R . Shtein 212 [ TELA916 ] (isotype, TELA!) .

Diagnosis:—Differs from K. guignardii var. guignardii by having a calyx tube and free sepal segments that are adpressed to the corolla tube; by having corolla lobes that are apically obtuse; and by having carpels that are not distinctly divergent at seed maturity.

Description:— Leaf blade 45–70 × (3–)5–10(–15) mm at maturity; calyx tube and free sepal segments adpressed to corolla tube; sepals 12–16 mm long, 10–11 mm across where fused, fused for ± 2.5–4.0 mm; corolla 17–21 mm long; tube cylindrical-campanulate, flared towards the mouth; lobes ± 9–11 × 6–9 mm, apically obtuse; carpels not distinctly divergent at seed maturity; styles ± 19–21 mm long; scales ± 1.5–2.0 × 2.0– 2.5 mm.

Flowering time:—Late-February to April (northern hemisphere) i.e., late-winter to early-spring.

Distribution:—Around Itafy and Toliara, Atsimo-Andrefana region, southwestern Madagascar ( Fig. 7 ). While K. guignardii var. schistosepala and K. scandens have partially sympatric geographical distribution ranges, these two entities can be easily distinguished by: (1) the shape of the calyx; (2) the calyx tube: free sepal segment length ratio; (3) the deeply split sepal segments of K. guignardii ; and (4) the narrowly obovate-oblong shape of the free corolla segments of K. guignardii , which is unique in K. ser. Vilana.

Additional material examined:—P-P00431145.

Etymology:—The varietal epithet is derived from New Latin (Ancient Greek σχιστός) ‘skhistós’, “cloven, divided”, and ‘sepala’, “sepals” to denote the short calyx tube and the much longer, acute free sepal segments. This trait is shared by the autonymic variety of K. guignardii as well as some of the varieties of K. beauverdii . However, in the case of K. beauverdii the calyx tube is differently shaped and the sepals are more ovate, while in K. guignardii var. guignardii the calyx and sepals are spreading, and not adpressed to the corolla.

E. Kalanchoe scandens Perrier de la Bâthie (1928: 28)

Homotypic synonym:— Bryophyllum scandens (H.Perrier) Berger (1930: 412) . Type:— MADAGASCAR. Southern Madagascar. Bara Plateau. Dry woods, basalt and limestone, on both banks of the Fiherenana River, cultivated in Antananarivo, received at Herb. P on 21 February 1928, [J.M.] H.[A.] Perrier de la Bâthie 17884 (lectotype, P P-P00374191!), designated by Boiteau & Allorge-Boiteau (1995: 86). This lectotype consists of at least four specimens (see discussion below), second-step lectotype, here designated.

Other synonym:— Kalanchoe beauverdii var. parviflora Boiteau & Mannoni (1949: 13) . Type:—[J.M.] H.[A.] Perrier de la Bâthie 17884 (lectotype, P P-P00374191!), designated here.

Nomenclatural note:— Boiteau & Mannoni (1949: 12) at first included both Kalanchoe juelii and K. scandens in the synonymy of K. beauverdii . However, one page further on, “PERRIER DE LA BATHIE 10.088 (type de K. Jueli)” and “[PERRIER DE LA BATHIE] 17.884 (type de K. scandens )” are cited as part of the material that represents the concept of Boiteau & Mannoni (1949: 13) of what constitutes K. beauverdii var. parviflora , a taxon treated at the rank of variety, therefore. Apart from these two specimens they additionally cited a range of other specimens. However, Boiteau & Mannoni (1949: 13) did not designate any of these specimens as the type of their K. beauverdii var. parviflora . Under Turland et al. (2018: Art. 6.11–6.13), Boiteau & Mannoni (1949: 13) validly published a replacement name, K. beauverdii var. parviflora , because a potential replaced synonym is cited, in this instance K. juelii or K. scandens . The decision regarding which of these potential replaced synonyms is the actual replaced synonym is determined through lectotypification, which we do here, based on Perrier de la Bathie 17884 (P), i.e., the type of K. scandens . This leaves K. beauverdii var. juelii , which produces rather large flowers ( Fig. 2 ), available.

Note on the type:— Perrier de la Bâthie (1928: 29) cited two specimens in the protologue of the name K. scandens : (1) [ J. M.] H.[ A.] Perrier de la Bâthie 17884; and (2) [ R.] Decary 4654. These two specimens constitute original material. Furthermore, at least four specimens are deposited at Herb. P under [ J. M.] H.[ A.] Perrier de la Bâthie 17884. These are: (1) MNHN-P-P00374191; http://coldb.mnhn.fr/catalognumber/mnhn/p/p00374191; (2) MNHN-P- P00374192 ; http://coldb.mnhn.fr/catalognumber/mnhn/p/p00374192; (3) MNHN-P-P00374193; http://coldb.mnhn. fr/catalognumber/mnhn/p/p00374193; and (4) MNHN-P-P00431144; http://coldb.mnhn.fr/catalognumber/mnhn/p/ p00431144. The fourth specimen, P00431144 , is not available for examination online .

The first three of these Perrier de la Bâthie specimens are available for examination online, and all carry virtually identical handwritten labels, presumably prepared by Perrier de la Bâthie, in the lower left corner. The word “type” is included on all three labels. We interpret these specimens as a single gathering of a single taxon ( K. scandens ) prepared at the same time (but see below) by Perrier de la Bâthie from a single locality. The three specimens that can be examined online were not dated by Perrier de la Bâthie; however, Herb. P received P00374191 on 21 February 1928, while both P00374192 and P00374193 were given to Herb. P by Perrier de la Bâthie in 1932. Perrier de la Bâthie presumably at first kept the latter two specimens in his personal herbarium before eventually donating them to Herb. P. All these specimens are syntypes . In a second-step lectotypification, under Turland et al. (2018: Art. 9.17), we here designate MNHN-P-P00374191, the earliest of these Perrier de la Bâthie specimens received at Herb. P, as lectotype .

Description:—Perennial, climbing, shrub-like, much-branched, glabrous, flimsy succulent, of variable height depending on plants with which it grows and that provide support for the scandent stems and branches. Stem and branches thin, up to ± 3 mm in diameter, growing upwards, climbing and twining into and leaning on surrounding plants, or variously dangling, metallic greenish purple at first, later whitish grey, stem much-branched, wiry to hard-succulent below; internodes distinctly swollen, scarred and minutely spinulescent. Leaves somewhat variable, distinctly curved downward with the apical portion rolled down further to assist climbing, smooth, succulent, sessile or rarely very slightly subsessile, ± channelled above, convex below, dark metallic brown to metallic green and variously purplish-infused, shiny, sometimes with a waxy bloom; petiole mostly absent; blade 20–100 × 3–10(–13) mm, generally narrowly linear to lanceolate to ovate-oblong towards inflorescence, succulent; base barely amplexicaul, slightly broadened, rounded on the sides, barely reaching the internodal spike; margins smooth throughout to irregularly dentate in upper ⅓ to ¼, sometimes irregularly brown-spotted; apex acute or blunt, with 1–2(–6) easily caducous bulbils. Inflorescence a terminal, few- to many-flowered cyme, generally short, leaning to drooping; peduncle indistinct, often decurved, metallic greenish purple; pedicels 3–7(–10) mm long, dull dark green, glabrous. Flowers 3–5(–7) in a cyme, pendent, glabrous, subtended by small, succulent, leaf-like bracts that persist for a long time, dull dark greyish green, densely infused with purple veins in a longitudinal network, longitudinally more intensely infused with purple in centre of petal abaxially and along petal margins, waxy bloom absent, papery when dry; calyx consisting of 4 sepals, round, ± 4-angled, tubular for ± ½–⅔, shiny mid- to dark green-brown, very faintly infused with minute evenly distributed purple and white spots, some purple spots arranged in faint longitudinal lines; sepals (11–) 13–16 mm long, 5–6 mm across where fused, free portion triangular-ovate, fused for ± 6–8 mm, acute-tipped, obscuring ± ½ of the corolla tube; corolla 25–30 mm long; tube 12–15 mm long, cylindrical to campanulate, somewhat to strongly flared at the mouth; lobes ± 12–15 × 6–7 mm, narrowly ovate to obovate, tapering apically, acute, mucronate. Stamens 8, inserted low down in corolla tube, at ± just above lower level of carpels, all well-exserted; filaments of two lengths, ± 14–18 mm long, thin, light green, very strongly purplish red-infused upwards; anthers ± 1.0– 1.5 mm long, purplish black, ovoid to hastate, well-visible at the corolla mouth. Pistil consisting of 4 carpels; carpels ± 4–6 mm long, shiny mid-green, purple-infused higher up, narrowly oblong, attenuate towards styles; styles ± 12–16 mm long, virtually throughout dark purple; stigmas very slightly capitate, green; scales ± 1.5 × 2.0 mm, free, ± square, slightly wider than long, often tapering upwards, upper corners slightly rounded, slightly tooth-like indented above. Follicles 5–7 mm long, light green at first, drying light brownish green to greyish brown, later brittle, grass spikelet-like, tightly enveloped in dry, persistent, light to dark purple, nearly black remains of corolla and fleshy, dull light green remains of calyx, splitting longitudinally, dry styles persistent for a long time. Seeds (0.75–)1.00(–1.25) mm long, light to dark to reddish brown, very narrow, tapering to one end, slightly oval to ribbon-like in outline, often banana-shaped-curved, minutely apiculate, faintly longitudinally striated. Chromosome number unknown.

Distribution:—Haute-Matsiatra, Ihorombe, and Atsimo-Andrefana regions, southwestern Madagascar.

Additional material examined:—P-P00431149; P-P00431155; P-P00431156; P-P00431157; P-P00438278.

Figures

FIGURE 1. Comparison of leaves and stems of representatives of Kalanchoe ser. Vilana, not to scale. A. K. costantinii var. unguifera (R. Shtein 957). B. K. costantinii var. costantinii (R. Shtein 901). C. K. beauverdii (R. Shtein 391, epitype). D. K. beauverdii var. pertinax (G.F. Smith 1126, type). E. K. beauverdii var. juelii (R. Shtein 361). F. K. beauverdii var. juelii (R. Shtein 921). G. K. guignardii var. schistosepala (R. Shtein 212, type). H. K. scandens (R. Shtein 818). I. K. ×rechingeri (R. Shtein 148). Plants cultivated in Israel and South Africa. Photograph credits: all Ronen Shtein, except D, Gideon F. Smith.

FIGURE 2. Comparison of the flowers of representatives of Kalanchoe ser. Vilana, to scale. A. K. costantinii var. unguifera (R. Shtein 957). B. K. costantinii var. costantinii (R. Shtein 901). C. K. beauverdii var.juelii (R. Shtein 921). D. K. beauverdii (R. Shtein 391, epitype). E. K. beauverdii var. pertinax (G.F. Smith 1126, type). F. K. scandens. G. K. guignardii var. schistosepala (R. Shtein 212, type). Plants cultivated in Israel, Italy, and South Africa. Photograph credits: A, B, D, G, Ronen Shtein; C, Patrizia Simbola; E, F, Gideon F. Smith.

FIGURE 3. Kalanchoe schizophylla. A. Buds and inflorescence bulbil clusters. B. Flowers and inflorescence bulbil clusters. C, D. Leaf shape variation between two distinct forms, asymmetrical pinnation, non-woody stems. E, F. Selected specimens held at Herb. P, vegetative (P-P00443969) and floral parts (P-P00443964). Elements E–F to scale. Plants cultivated in Israel and Italy. Photograph credits: A, B, Patrizia Simbola; C, D, Ronen Shtein; E, F, Herb. P.

FIGURE 4. Comparison of selected characters of representatives of Kalanchoe ser. Vilana, to scale, based on preserved material held at Herb. P. A. Type of K. costantinii var. unguifera, A1 flowers and A2 leaves. B. Epitype of K. costantinii var.costantinii, B1 flowers and B2 leaves. C. Syntype of K. scandens (P-P00374193), C1 flowers and C2 leaves. D. Type of K. beauverdii var. juelii, D1 buds and D2 leaves. E. Type of K. guignardii, E1 flowers and E2 leaves. F. Material referable to K. guignardii var. schistosepala (P-P00431145), flowers. G. Lectotype of K. beauverdii var. beauverdii, flowers. Photograph credits: all Herb. P.

FIGURE 5. Inter-series natural hybrids involving climbing kalanchoes. A. Type of K. ×poincarei at Herb P. B. Material previously determined as K. ×poincarei at Herb P (P-P00444059). C. A specimen of K. ×rechingeri at Vienna (W 1954-0007470). D, E, F. K. ×rechingeri (R. Shtein 148) in flower and in bud, cultivated in Israel. Elements A–C to scale. Photograph credits: A–B, Herb. P; C, Herb. W; D–F, Ronen Shtein.

FIGURE 6. Corolla segments viewed from the mouth (i.e., from below) of selected representatives of Kalanchoe ser. Vilana. A. K. beauverdii (R. Shtein 391, epitype). B. K. guignardii var. schistosepala (R. Shtein 212, type). C. K. costantinii var. unguifera (R. Shtein 957). D. K. costantinii var. costantinii (R. Shtein 901). Not to scale, grid segment in each element represents 5 mm. All photographs by R. Shtein.

FIGURE 7. Geographical distribution ranges of representatives of Kalanchoe ser. Vilana recognised in this study. The precise localities of the types of K. schizophylla, K. beauverdii var. beauverdii, K. beauverdii var. pertinax, and K. costantinii var. costantinii in Madagascar are insufficiently known to be placed (see text for details).