Wittmackia mesoamericana (I.Ramírez, Carnevali & Cetzal) Aguirre-Santoro (2017: 636)

Aguirre-Santoro, Julián, 2018, Taxonomic revision of the Caribbean-endemic species of Wittmackia (Bromeliaceae), Phytotaxa 336 (2), pp. 101-147 : 126-127

10. Wittmackia mesoamericana (I.Ramírez, Carnevali & Cetzal) Aguirre-Santoro (2017: 636) . Basionym: Hohenbergia mesoamericana I.Ramírez, Carnevali & Cetzal in Ramírez-Morillo et al. (2010: 22). TYPE:— MEXICO. Quintana Roo: predio Punta Young, rancho Estrella del Sur, fracción B y rancho Estrella del Sur, fracción C, flexión derecha del km 266 + 200, de la carretera federal 307 Reforma Agraria-Puerto Juárez, tramo Tulum - Playa del Carmen, 0 m, 20º32’3”N, 87º9’50”W, 10 March 2008, W. Cetzal-Ix 20 (holotype CICY!, isotype MO!)

Plant terrestrial, cespitose, 130 cm tall; rosette broad. Leaves 66 cm long, coriaceous; sheaths conspicuous, subelliptical, 13–16 × 10.5–14 cm, green to black castaneous, lepidote on both surfaces, entire; blades lingulate, 120 cm long, 14 cm wide at the base, 11.2 cm wide in the middle, green, nervose, lepidote abaxially, glabrescent adaxially, apex initially acute to rounded, then ending in a sharp and acuminate mucro, margins serrate, the teeth evenly distributed, hook-shaped, mainly antrorse, castaneous, 1.5 mm long. Inflorescence erect to inclined; peduncle almost completely exposed out of the rosette, stout, rigid, 54–71 cm long, 5–10 mm in diameter, green, densely floccose, central internodes 5–9 cm, distal internodes 4.2 cm; peduncle bracts longer than the internodes, marcescent, membranaceous, nervose, light green, the central erect, imbricate, linear-lanceolate, 9–16 × 0.5–1.3 cm, lepidote on both surfaces, apex attenuate, margins serrulate, the teeth evenly distributed, the distal ones forming an angle of 30º–60º with the rachis, lax, linear, 9–15.5 × 0–5- 0.9 cm, lepidote on both surfaces, apex attenuate, margins serrulate, the teeth evenly distributed; fertile part of the inflorescence conical, 29–48 cm long, 9.4 cm wide in the middle, 1-divided, branches 21 to 50 in number, rachis straight, green, 24–43 cm long, 7 mm in diameter, densely floccose. Primary bracts similar to the peduncle bracts, gradually diminishing in size towards the apex of the inflorescence, diverging from the rachis, marcescent, membranaceous, nervose, longer than the branches; the basal ones linear, 8.2–14.5 × 0.4–0.6 cm, light-green, floccose-lepidote on both surfaces, apex attenuate-caudate, margins serrulate, the teeth irregularly distributed; the apical ones linear-lanceolate, 1.9 × 0.3 cm, light green, lepidote on both surfaces, entire, apex attenuate. Spikes cylindrical to long-ovoid, 3.2–4.9 cm, 2–2.7 cm wide in the middle; stipes exposed, 3–6 mm long, 4–5 mm in diameter, terete, densely floccose, 15–45 flowered; rachis 4.5 cm long. Floral bracts gradually diminishing in size towards the apex of the spike, partially enfolding the ovaries, imbricate, suberect to forming an angle of 30º–60º with the rachis, slightly concave, coriaceous, ovate, 5.7 × 5.6 mm wide, green, nervose, floccose-lepidote on both surfaces, minutely serrulate, occasionally entire, apex acuminate, gradually turning into a sharp mucro of 4.2 mm long. Flowers suberect to forming an angle of 30º–60º with the rachis, 16–17.3 mm long. Calyx dorsiventrally compressed; sepals coriaceous, triangular, asymmetrical, 5 mm long, 4–4.1 mm wide at the base, the unwinged side 1.8 mm wide, the winged side 2.2 mm wide, green, nervose, sparsely floccose, entire, apex initially acute, then ending in a sharp and acuminate mucro of 2.6 mm long. Corolla tubular, apically spreading; petals oblong to subspatulate, 12.5–13.4 × 2.4–3 mm, green, basally white, glabrous, entire, apex acute; petal appendages flanking the antepetalous stamens, originating at 3.1–4.2 mm from the petal base. Stamens included; filaments flattened, 8.3–9 mm long, 0.2 mm in diameter, white; anthers parallel versatile, rectangular to lanceolate, 2.7–2.9 × 0.5–0.7 mm, cream, apiculate. Ovary ovoid, 4.4 mm long, 5.7 mm in diameter, green, floccose-lepidote; epigynous tube 1.2 mm long; ovules more than 30 per ovary, globose. Style longer than the stamens, cylindrical, 11.2 mm long, green; stigma green, 2 mm long. Fruits unknown ( Fig. 12 ).

Etymology:— The specific epithet indicates that this is the only species of the Caribbean-endemic Wittmackia that occurs in Mesoamerica.

Distribution, habitat, and phenology:— Wittmackia mesoamericana is only known from one population in the coastal region of the Yucatan peninsula in Mexico at sea level ( Fig. 2 ). It grows as epiphyte or terrestrial on forested limestone formations. Collected in flower from February to March.

Conservation status:— In the protologue, Ramírez-Morillo et al. (2010) highlighted the imminent threats to the habitat of Wittmackia mesoamericana and categorized the species as Critically Endangered (CR D).

Taxonomic comments and affinities:— Wittmackia mesoamericana is similar to W. caymanensis because of its floccose inflorescence rachis, primary bracts much longer than the inflorescence branches, clearly stipitate spikes, long floral bract mucros (4–5 mm long), long sepal mucros (2–5 mm long), and green petals. However, W. mesoamericana is different from W. caymanensis by its broader leaf blades (14 cm vs. 5–12.7 cm wide at the base); shorter (3–5 mm vs. 6–18 mm long) and stouter stipes (4–5 mm vs. 2–3 mm in diameter); broader spikes (2.2–2.7 cm vs. 1.2–2 cm wide); longer flowers (16–17.3 mm vs. 13.5 mm long); longer and broader petals (12.5–13.4 × 2.4–3 mm vs. 8.3–9.3 × 1.2 mm); and petal appendages detaching at 3.1–4.2 mm from the petal base (vs. 1.7 mm). The affinity between W. mesoamericana and W. caymanensis is supported by the phylogenetic study of Aguirre-Santoro et al. (2016b), which shows these species as sister taxa. In the protologue W. mesoamericana is compared with W. spinulosa because of their similar inflorescence architecture but, more importantly, because both species exhibit green petals. Wittmackia mesoamericana , however, mainly differs from W. spinulosa by its longer and broader leaf blades (120 × 14 cm vs. 41–58 × 9.6–11 cm long; longer peduncle (54–71 cm vs. 21.8–33– 5 cm long); broader inflorescence (ca. 9.4 cm vs. 4.6–8.7 cm wide); inflorescence branches laxly arranged along the rachis (vs. congested) and divergent (vs. suberect); and broader spikes (2.2–2.7 cm vs. 0.8–1.5 cm wide).

Additional specimens examined:— MEXICO. Quintana Roo: Solidaridad, predio Punta Young, rancho Estrella del Sur, fracción B y rancho Estrella del Sur, fracción C, flexión derecha del km 266 + 200, de la carretera federal 307 Reforma Agraria-Puerto Juárez, tramo Tulum - Playa del Carmen. Florecida de la planta original colectada en 10 marzo, 2008, 0 m, 20º32’3”N, 87º9’50”W, 1 February 2011, Ramírez et al. 1666 (CICY!, SEL!).

Figures

FIGURE 2. Geographic distribution of the Caribbean-endemic species of Wittmackia. A. Species occurring in Jamaica and Cuba, and species endemic to the western Caribbean. Star: W. caymanensis, triangle: W. mesoamericana, circle: W. penduliflora. B. Species endemic to Puerto Rico. Star: W. portoricensis, circle: W. antillana. C. Species endemic to Jamaica. Circle: W. laesslei, triangle: W. negrilensis, star: W. polycephala.D. Species endemic to Jamaica. Circle: W. rohan-estyi, triangle: W. spinulosa, star: W. urbaniana. E. Species endemic to Jamaica. Circle: W. fawcettii, triangle: W. jamaicana, star: W. inermis. F. Species endemic to Jamaica. Circle: W. abbreviata, star: W. distans, square: W. eriostachya.

FIGURE 12. Wittmackia mesoamericana. A. Inflorescence and part of the leaf blades. B. Calyx and corolla of rehydrated flower. C. Sepals D. Petal. E. Petal appendages. F. Apical portion of the stamen. G. Apical portion of the style and stigma. (A–G: Ramírez 1666. Photos of living specimens: I. Ramírez).