Tillandsia alcatrazensis Sabino & Leodegario, 2023

Sabino, Gabriel Pavan, Leodegario, Marcio De Melo, Marcusso, Gabriel Mendes, Shimizu, Gustavo Hiroaki, Koch, Ingrid, Tavares, Danilo Ulbrich & Pinheiro, Fábio, 2023, Tillandsia alcatrazensis (Bromeliaceae), a new endemic species from Alcatrazes Island in southeastern Brazil, Phytotaxa 607 (3), pp. 213-221 : 215-219

Tillandsia alcatrazensis Sabino & Leodegario , sp. nov. ( Figs. 2–5 )

Type: — BRAZIL. S ã o Paulo: S ã o Sebasti ã o, Ilha de Alcatrazes, Vegetaç ã o rupícola na ascens ã o da trilha entre o tablado e a base da Marinha (Refúgio de Vida Silvestre do Arquipélago de Alcatrazes), 24°6’1.30”S, 45°41’30.27”W, 207 m, 19 August 2022, G.P. Sabino, V.A. Kamimura & I.M. Cunha 551 (holotype UEC, isotype RB) .

Diagnosis: — Tillandsia alcatrazensis is similar to T. geminiflora , but is distinguished by, larger size (21–34 vs. 12–20 cm tall), longer floral bracts (1.5–2.5 cm vs. 1–1.6 cm), longer flower (ca. 3 cm vs. 1.8–2 cm), longer petals (2.3–2.8 vs. 1.5–1.8), and color (white vs. pink or salmon), longer stamens (ca. 17mm vs. 10mm), and longer style (ca. 2 vs. ca. 0.7 cm).

Description:— Plant usually rupicolous or rarely epiphytic, heliophytic, forming clumps. Plants flowering 21–34 cm long, 20–30 cm in diameter. Roots present. Leaves 8.6–20 cm long, numerous, densely spirally arranged, recurved or ascending, sparsely to densely lepidote on both sides, vinaceous or greenish-cinereous; sheath 1.1–4 × 0.9–2.7 cm, narrowly elliptic to obovate; blade 7.5–16 × (0.5–) 0.7–1.7 cm, very narrowly triangular, apex long attenuately acute. Peduncle 11–15 cm long, 2–3.3 mm in diameter, erect or suberect, greenish-orange; peduncle bracts 10.9– 13.9 × 1.3–1.5 cm, numerous, foliaceous, imbricate, completely covering the peduncle, vinaceous, salmon or pink; Inflorescence fertile part 3.5–11.5 × 3.5–10.5 cm, suberect, compound, once branched or rarely twice branched, a globose to pyramidal panicle; primary bracts 2.5–8.5 × 1.1–1.7 cm, gradually decreasing in size distally, lanceolate to ovate, attenuate to acuminate, salmon or reddish; branches 2–5-flowered, with a sterile terminal flower bud, the lower ones occasionally with a 1–2 flowered secondary branch; floral bracts 1.5–2.5 × 0.7–1.2 cm, elliptic, reddish-salmon, lepidote, frequently crenate. Flowers sessile, distichous, ca. 3 cm long; sepals 14–20 × 4–6 mm, symmetrical, lanceolate, apex attenuately acute, free, sparsely lepidote, salmon or reddish; petals spathulate, 2.3–2.8 × 0.5 cm, free, the blade spreading to reflexed, apex rounded, white; corolla ca. 1.4 cm in diameter at the apex. Stamens included, ca. 17 mm long; filament ca. 15 × 0.5 mm, plicate, flattened, flaccid, sublinear, whitish, slightly translucent, free; anther 2–3 × 0.5 mm, subbasifixed, base and apex acute, yellowish. Pistil exceeding the stamens; ovary 2–4 × 1–2 mm, greenish to yellowish, ovoid; style ca. 20 mm long, 0.5 mm in diameter, erect, whitish; stigma simple-erect, patent, white; Fruits and seeds not seen.

Etymology:— The specific epithet refers to the Alcatrazes Island, the site where this new species was discovered.

Phenology:— The blooming season spreads into the dry season of southeast Brazil, from May to August. Some individuals were also found blooming in March. Fruits not seen.

Distribution and habit:— Known only from the type locality, growing mainly rupicolous, especially on the top of the granitic outcrops of the island, and rarely as epiphyte in forest patches on the Alcatrazes Island, municipality of S ã o Sebasti ã o, state of Sao Paulo, southeastern Brazil. The Alcatrazes Island is the main island of an archipelago with the same name, and it is a fully national protected area since 2016 (ICMBio 2020). It is considered an “island of an island” as it is an inselberg-like environment in the Atlantic Ocean, situated 35 km away from the mainland. The landscape of the island is characterized by rocky outcrops vegetation and patches of forest, with influences from the coastal Atlantic Forest of the mainland. The terrain is extremely steep, and there is an Atlantic Forest cover where soil is accumulated. However, on rock outcrops, where the soil is scarce or absent, the forest gives place to shrubby or herbaceous vegetation.

The island is well known for its stunning biota, home of plant species endemic to the island (e.g. Anthurium alcatrazense Coelho & Catharino [2008: 830] ; Begonia venosa Skan ex Hooker [1899 : pl. 7657]; Neoregelia insulana Leme ( Leme & Kollmann 2013: 28), as well as animals (e.g. Ololygon alcatraz Lutz [1973: 2] ; Bothrops alcatraz Marques, Martins & Sazima [2002: 304] ). The geographical isolation may limit the gene exchange between insular and mainland populations, increasing the genetic differentiation and reproductive isolation of species found at Alcatrazes Island ( Pinheiro et al. 2021).

The populations of Tillandsia alcatrazensis frequently form densely aggregated specimens, growing on rock, where there is a little organic substrate accumulation or directly on the rock, and in full sunlight. Populations were also found growing on sloping granitic cliffs and rarely as an epiphyte. On the top of the granitic outcrops, where the populations are denser, T. alcatrazensis frequently grows together with Trilepis lhotzkiana Nees ( Arnott 1834: 267) , Anthurium alcatrazense , Neoregelia insulana , Tillandsia cf. araujei Mez (1894: 600) , Coleocephalocereus fluminensis ( Miquel 1838: 48) Backeberg (1942: 53) , and Rhipsalis grandiflora Haworth (1819: 83) .

Additional specimens examined (paratypes): — BRAZIL. S ã o Paulo: S ã o Sebasti ã o, Ilha de Alcatrazes, vegetaç ã o rupícola na ascens ã o da trilha entre o tablado e a base da Marinha (Refúgio de Vida Silvestre do Arquipélago de Alcatrazes), 9 May 2022, 24°06’02”S, 45°41’30”W, 227 m, G.P. Sabino, F. Pinheiro, B.L. Arida & W.L.S. Júnior 456 ( PMSP, UEC). Ibidem, floresceu em cultivo na casa de vegetaç ã o da UNICAMP, 23 March 2023, G.P. Sabino, F. Pinheiro, B.L. Arida & W.L.S. Júnior 772 ( UEC). Ibidem, floresceu em cultivo na casa de vegetaç ã o da UNICAMP, 23 March 2023, G.P. Sabino, F. Pinheiro, B.L. Arida & W.L.S. Júnior 773 ( UEC). Ibidem, na base do Pico da Boa Vista , floresceu em cultivo na casa de vegetaç ã o da UNICAMP, 23 March 2023, 24°06’16.75”S, 45°41’47.53”W, 270 m, G.P. Sabino, T.M. Lima & R. Silva 774 ( RB) .

Conservation status: — The GeoCAT ( Bachman et al., 2011) retrieved that the estimated occurrence area for Tillandsia alcatrazensis is 4 km ². Based on this value and the IUCN categories and criteria (IUCN 2022), we have preliminarily classified this new species as Critically Endangered CR B1ab (i,ii,iii,iv). Illegal collections cannot be ruled out even in a species inhabiting a fully protected area (ICMBio 2020). In 2004, the island also suffered a major fire caused by a Brazilian navy training course, destroying 20 hectares of vegetation and causing the proliferation of exotic plants such as Melinis minutiflora Palisot de Beauvois (1812: 54) (ICMBio 2020). This invasive species, in addition to competing with other species, can accumulate dense biomass, which increases the risk of future fires.

Taxonomic notes:— Tillandsia alcatrazensis belongs to subgenus Anoplophytum by the following features: included stamens, strongly plicate filaments, and slender style much longer than the ovary ( Smith & Downs 1977). It is morphologically related to Tillandsia geminiflora Brongniart (1834: 186) , Tillandsia gardneri Lindley (1842 : sub t. 63), and Tillandsia globosa Wawra (1880: 222) ; and a comparison with these species is presented on Table 1 . In relation to T. geminiflora , this new species differs by the main lifestyle (rupicolous vs. epiphytic), its larger size when in bloom, longer flower bracts, longer flower, longer petals and color, longer stamen, and longer style (see diagnosis and Table 1 ). In relation to T. gardneri it differs by the larger size in bloom, longer inflorescence, longer flower, number of flowers per branch, longer floral bracts, longer petal, longer stamen and longer style. T. alcatrazensis can also be confused with T. globosa , but differs from it by its larger size when in bloom, leaf color, longer inflorescence, longer flower, longer floral bracts, longer petal, longer stamen, and longer style ( Table 1 ).

We observed three other Tillandsia species thriving sympatric on Alcatrazes island: T. gardneri and T. cf. araujei (both of subg. Anoplophytum ) and T. usneoides (L.) Linnaeus (1762: 411) of subg. Diaphoranthema .

Figures

FIGURE 2. Tillandsia alcatrazensis in habitat. A. Growing as a rupicole on rocky substrate of the granitic outcrops, photo by Gabriel Pavan Sabino. B. Close up of the flowers, photo by Vitor de Andrade Kamimura.

FIGURE 3. Tillandsia alcatrazensis. A. Habit. B. Primary branch (left) and primary branch with a secondary branch (right). C. flower with a floral bract. D. Floral bracts. E. Sepals. F. Petals. G. Stamens. H. Gynoecium. Bars: A = 2 cm; B–C= 1 cm; D= 1 cm; E= 1 cm; F= 1 cm; G, H = 0.5 cm. (Photos by G.P. Sabino based on G.P. Sabino 551, 772).

FIGURE 4. A–J Tillandsia alcatrazensis (G.P. Sabino 551). A. Habit. B. Inflorescence branch. C. Floral bract and flower. D. Detail of the lepidote sepal. E. Floral bracts. F. Sepals. G. Petals. H. Stigma. I. Gynoecium. J. Stamen. (Illustration by Danilo Ulbrich Tavares).

FIGURE 5. Tillandsia alcatrazensis phenotypical variation. A–C. Front viewof the inflorescences.D–F. Lateral view of the inflorescences. G–I. Habit. Bars: A–F = 1 cm; G–I = 2 cm. Photos by G.P. Sabino based on G.P. Sabino et al. 772 (A,D,G), GPS et al. 773 (B,E,H) and GPS et al. 774 (C,F,I).