Tillandsia geminiflora Brongniart (1829

Rossado, Andrés J., Donadío, Sabina & Bonifacino, José M., 2024, A taxonomic revision of Tillandsia (Tillandsioideae, Bromeliaceae) from Uruguay, Phytotaxa 667 (1), pp. 1-90 : 1-90

6. Tillandsia geminiflora Brongniart (1829 [1834]: 186). Figs. 5F , 21 , and 22.

≡ Anoplophytum geminiflorum (Brongn.) É. Morren (1880a: 191) . Type (lectotype, first-step designated by Smith & Downs 1977: 806 [as “ holotype ”]):— BRAZIL. Santa Catarina: [Florianópolis], 4 October 1822, Dumont d’Urville s.n. (P [two specimens], second-step lectotype designated here: P00438705 [online image!]; syntype: P00753228 [online image!]).

Plants acaulescent, not branched or sometimes few-branched and then forming dense clumps up to 45 cm in diameter. Roots 0.5–1 mm in diameter. Leaves spirally arranged, clustered forming a rosette, light green to green-grayish, sometimes with purple spots (especially on sun-exposed plants); sheaths 15–30 mm wide, nearly indistinguishable from the blade, basally glabrous, densely lepidote towards the blade; blades 100–210 × 11–26 mm, divergent to reflexed (mainly spreading), very narrowly triangular, channelled from the base to almost the apex, thin, densely appressed-lepidote throughout, trichomes (nearly) symmetric. Inflorescences compound, 1-branched, sometimes 2-branched; peduncles partially exposed to wholly covered by bracts, 4.5–13 cm long, 4.5–6.5 mm in diameter, sparsely lepidote to almost glabrous; peduncle bracts 4 to 9 in number, mainly leaf-like, erect to divergent, evenly distributed along the peduncle, imbricate (sheaths covering at least the base of the sheath of the following bract); upper peduncle bract with developed blade; sheath 18–50 × 8–16 mm, (narrowly) elliptic-ovate, pink, densely lepidote throughout; blade 25–70 mm long. Inflorescence fertile part 4–15 cm long, ellipsoid; axis 2.5–13 cm long, for most part exposed, straight to curved; branches 7 to 30 in number, spirally arranged, divergent to suberect; basal primary bracts like the upper peduncle bracts, exceeding the branches; upper primary bracts shorter and mostly bladeless; primary peduncles to 28 mm long, bractless; spikes distichously and subdensely 2 to 4-flowered, to 50 mm long, complanate; rachis exposed, reddish to reddish-pink, subdensely lepidote or sparsely lepidote. Floral bracts 8–16 × 5–9 mm, shorter than the sepals, subdensely distributed (2–3 times longer than the internodes), not imbricate, clasping the basal half of the flower, bladeless, ovate to triangular-ovate, carinate, red or reddish-pink, subdensely to densely lepidote. Flowers 16–22 mm long, scentless; sepals visible, 10–17 × 3.7–5 mm, connate at the base for (0.1–) 0.5–6 mm (adaxial ones generally more connate between them than with the abaxial one), narrowly elliptic or sometimes narrowly elliptic-ovate, carinate (more noticeable on the adaxial sepals), reddish-pink, subdensely to densely lepidote throughout; petals 16–23 mm long, spatulate; claw ca. 2.5 mm wide white but apically pink; limb 3.7–5 mm wide, spreading, elliptic, pink, margins entire or slightly irregular; stamens 11–16 mm long, included, equaling or shorter than the pistil; filaments 8–13 mm long, plicate for up to 2 mm in the apical half; pollen white; pistil 10–18 mm long, included (reaching the throat of the corolla); ovary 2–3.2 × 1.7–2.5 mm, shortly obovoid, abruptly contracted into the style; style 8–13 mm long, 4–5 times as long as the ovary, white and apically pink; stigmas conduplicate-spiral. Capsules 27–42 × 2.3–3.5 mm, much exceeding its respective floral bract, cylindrical-prismatic, apex truncate and short-beaked.

Vernacular names:— Not known. Possibly clavel del aire.

Classification:— Tillandsia geminiflora belongs to the T. gardneri complex (sensu Barfuss et al. 2016) based on its morphological characteristics, and the molecular phylogeny obtained by Vera-Paz et al. (2023). There are two varieties described for T. geminiflora ; all the specimens analyzed for Uruguay and neighboring areas correspond to the typical variety.

Distribution and habitat:— Suriname, Brazil, Paraguay, Argentina, and Uruguay. Tillandsia geminiflora is broadly distributed from northeastern to southern Brazil while in Argentina, it is restricted to Misiones province (Paranaense Phytogeographic Province).

The presence of this species in Uruguay is associated with woody vegetation (mostly moist hillside and riverside forests) of the Laguna Merín basin placed in eastern Uruguay (Cerro Largo, Treinta y Tres, Rocha, and one record for northern Lavalleja; Fig. 22 ). There, T. geminiflora exclusively grows as an epiphyte on trunks and even small-diameter branches, mostly inside the forest under partly shaded conditions. It usually cohabits with other Bromeliaceae species (e.g. Aechmea recurvata (Klotzsch) L.B. Smith , T. aëranthos , T. stricta ), occasionally being the dominant species of the epiphytic community. The southern limit of distribution of T. geminiflora is located in Uruguay, specifically within the San Miguel National Park (Rocha; Fig. 22 ), where a large and dense population of this species extends along the riverside forest of the San Miguel River ( Fig. 21A ).

Phenology:— In Uruguay, Tillandsia geminiflora flowers during the spring, from mid-October to late November ( Fig. 4 ). Fruits begin to develop in November–December and continue growing in length until late December or January. Following this period, they remain without growth for six to eight months until seed dispersal, which takes place in winter (from June to September). In each plant, a period of 10 to 13 months occurs between the onset of the inflorescence emergence and the dehiscence of the capsules.

Reproductive observations:— The inflorescences of Tillandsia geminiflora are green while they develop (development of the inflorescence takes approximately two months), gradually turning pink close to the anthesis of the flowers. Each inflorescence simultaneously bears several open flowers, and remains flowering for approximately 20 to 30 days. Individual flowers remain open between three and four days (occasionally extending to five), which partially agrees with what is reported from Brazil ( Machado & Semir 2006). On the fourth or fifth day post-opening, the flower withers, which is evidenced by the color of the petals that changes from pink to brown ( Fig. 21D ). Following the conclusion of the flowering period, the peduncle, bracts, and sepals revert from pink to green, and they remain green and alive generally until the dehiscence of the capsules ( Fig. 21G ).

According to Varassin & Sazima (2000) and Machado & Semir (2006), Tillandsia geminiflora is pollinated by hummingbirds, in agreement with our own observations in Uruguay.

Conservation:— We consider Tillandsia geminiflora as Not Threatened in Uruguay. Despite having a relatively confined distribution within the country, T. geminiflora has several populations occurring mainly in well-preserved forests. Most of these populations are healthy and consist of a high number of individuals. Additionally, this species is present in three national protected areas: ‘Paisaje Protegido Paso Centurión y Sierra de Ríos’, ‘Paisaje Protegido Quebrada de los Cuervos y Sierras del Yerbal’, and “Parque Nacional San Miguel”.

Diagnostic characters:— In Uruguay, no other species is morphologically similar to Tillandsia geminiflora . Recognition of this species in the field is straightforward, facilitated by the distinctive combination of compound inflorescences and green leaves. Moreover, it is the only species of Tillandsia with pink petals, or carinate floral bracts within the country.

Background in Uruguay:— The first citation of Tillandsia geminiflora for the country was made by Smith (1933). The oldest herbarium specimen of this species was collected by Berro in 1902 from Isla del Parao, Treinta y Tres.

Note: — Smith & Downs (1977) cited d’Urville s.n at P as the “ holotype ” for Tillandsia geminiflora . This statement can be taken only as the first step of a lectotypification (ICN Art. 9.17, Turland et al. 2018), as two specimens of d’Urville, whose characteristics and label data are in agreement with the protologue of T. geminiflora , were found at P (P00438705 and P00753228). We designated P00438705 as the second-step lectotype for T. geminiflora , as it is a complete and well-preserved specimen. Additionally, this specimen has a drawing of the species by Dr. Lesson with annotations that in part are cited in the protologue.

Representative specimens examined:— URUGUAY. Cerro Largo: Sierra de Ríos , 23 October 1991, Grum et al. s.n. ( MVFA 20362 ) . Lavalleja: Desembocadura del Arroyo Corrales en el Cebollatí , February 1921, Schroeder s.n. ( MVV – Herb. Osten 13658) . Rocha: Balneario Saglia, Laguna Merín , 21 October 2012, Brussa & Gago 4939 ( MVJB) . Treinta y Tres: Río Tacuarí y ruta 18, 22 September 2013, Rossado et al. 215 ( MVFA) .

Figures

FIGURE 4. Phenology of Tillandsia species occurring in Uruguay. Divisions within each month indicate intervals of approximately 10 days, identified as the beginning, middle, and end of each month. Tillandsia loliacea is excluded due to lack of enough information. * Denotes species with cleistogamous flowers. ** Denotes species with insufficient data to ascertain the timing of fruiting or fruit dehiscence.

FIGURE 5. Illustrations of floral parts. A. Tillandsia aëranthos. B. T. ixioides. C. T. × marchesii. D. T. stricta. E. T. recurvifolia. F. T.geminiflora. From left to right: floral bract (stretched view), sepals (stretched view; adaxial sepals to the right), petal (stretched view), and pistil.A based on Rossado et al. 29 (MVFA; floral bract and sepals) and Haretche 807 (MVFA; petal and pistil); B based on Rossado et al. 455 (MVFA); C based on Rossado 463 (MVFA); D based on Rossado et al. 200 (MVFA; floral bract, petal and pistil) and Rossado 412 (MVJB; sepals); E based on Rossado et al. 366 (MVJB); F based on Rossado 17 (MVFA; floral bract, petal, and pistil) and MVFA 440 (sepals).

FIGURE 21. Tillandsia geminiflora.A. Habitat; riverside forest on the banks of the San Miguel River (Rocha, Uruguay).This population marks the southern limit of T. geminiflora distribution. B. Habit. C. Lateral view of the fertile part of the inflorescence. D. Frontal view of the inflorescence. E. Lateral view of the flowers. F. Detail of immature capsule. G. Plant with infructescence (Paso Centurión, Cerro Largo, Uruguay). Photos by Andrés Rossado.

FIGURE 22. Distribution map of Tillandsia geminiflora in Uruguay and neighboring areas.