Spathiphyllum maldonadianum Díaz Jim., 2022

Jiménez, Pedro Díaz, Dötterl, Stefan, Fuchs, Roman, Hentrich, Heiko, Pérez-Farrera, Miguel Ángel, Vega, José Padilla & Aguilar-Rodríguez, Pedro A., 2022, Two new species of Spathiphyllum (Araceae) from Tabasco, Mexico with notes on their floral scent, Phytotaxa 566 (1), pp. 121-132 : 123-126

Spathiphyllum maldonadianum Díaz Jim. , sp. nov. ( Fig. 2 )

Spathiphyllum maldonadianum can be confused with S. cochlearispathum , but it differs from that species in having the petiole longer than the blades and not sheathed up to the geniculum (vs. as long as the blade and sheathed near or up to the geniculum), blade of up to 47 primary veins per side (vs. less than 40), pistils up to 15 mm long (vs. less than 10 mm) and up to 11 ovules per ovary (vs. up to 16).

Type: — MEXICO. Tabasco: Municipio Teapa , Sierra el Madrigal, San José Puyacatengo, 17°31’N, 92°55’W, 188 m asl, 13 Aug. 2008, Pedro Díaz Jiménez 604 (holotype UJAT!)

Terrestrial; understory herb, frequently growing scattered in low densities. Up to 2.3 m tall; internodes short, up to 5.0 cm diam. LEAVES 166–250 cm long; petioles up to 1.80 times longer than the blades, 65–148 cm long, 8–10 mm diam., sheathed near the middle, or above to 11.5–60.0 cm from the geniculum, free portion terete, the sheath and free portion pale green and covered in white dots, sheath margins strongly wrinkled with a white edge up to 5 mm wide, straight or wavy, sometimes inrolled, light green; geniculum 3.5–7.5 cm long, 9–12 mm diam., yellowish-green and weakly covered in white dots; blades oblong, oblong-ovate or oblong-elliptic, widest at or just below the middle, 52–83 cm long, 22–32.3 cm wide, approx. 2.5–3 times longer than wide, cuspidate at apex, sometimes inrolled apically and forming a thin elongated tip of up to 5 cm, obtuse or rounded at base, subcoriaceous, dark green and glossy above, light green semi-glossy below, drying green to dark brown above, light brown below; midrib sunken and weakly covered in white dots, thicker than broad, dark green and glossy above, and light green to whitish below; primary lateral veins, 38–47 pairs, separated 6.5–25.0 mm, arising at an 60–80° angle, sunken and dark green above, light green below; minor veins dark green below. INFLORESCENCE erect, equal or taller than the leaves; peduncle 119–170 cm long, 7.2–13.0 mm diam., covered in white dots, green to light yellowish-green; spathe cucullate, oblanceolate or elliptic, 21–44 cm long, 15.3–17.4 cm wide, acuminate to narrowly acuminate apex, subcuneate, attenuate, oblique or sub-rounded at the base, decurrent up to 18 mm at the base, yellowish-green at anthesis, dark green at post-anthesis; spadix 10–21 cm long, 2.3–2.8 cm diam., cream-yellowish, emitting a strong and pleasant floral scent at anthesis, stipe 5–15 mm long, 8–10 mm diam., light green to yellowish-green at anthesis, dark green at post-anthesis; perianth with 6 free tepals, 2.2–3.0 mm long; up to 6 anthers, 1.8–2.1 mm long, thecae oblong, 1.0– 1.5 mm long; the pistils, sharply emergent, elongate-conic, 5–15 mm long, style 4.6–5.5 mm long, 1.5–2.0 mm diam. at the base; ovary 3-locular, 3–5 ovules per locule, 6–11 ovules per ovary. INFRUCTESCENCE 18–21 cm long, 2.7–3.3 cm diam.; berries obovoid to oblong, rostrate, 10–17 mm long, 3.3–6.0 mm wide, yellowish at maturity; seeds oblong, obovoid or oblique-ovoid, 2.3–3.8 mm long, light brown or dark brown and glossy when fresh.

Distribution, habitat, and conservation status: — Spathiphyllum maldonadianum is endemic to Mexico, known only from the Sierra region of the state of Tabasco ( Fig. 1 ). It grows mainly as an understory species in evergreen tropical forests, sometimes on riverbanks, often scattered or in small populations of few individuals, between 40 and 800 m asl. Due to its proximity to the northern highlands of Chiapas, S. maldonadianum may be also present in the state of Chiapas. By its distribution area (according to the GeoCAT program) and applying the IUCN Red List Categories and Criteria (B1 and B2), S. maldonadianum is not considered in any endangered status ( IUCN 2012). However, we believe that due to the accelerated deforestation in the area, the species could be considered a threatened species.

Phenology, floral scent and floral visitors: —According to the specimens reviewed and collected at anthesis and post-anthesis, flowering occurs in February and March, and from June to September. From the early hours of the morning, the spadices of S. maldonadianum emitted a strong and pleasant floral scent, sometimes perceptible several meters away. In the afternoon, the scent was less intense. The scented bouquet contained overall 41 volatile compounds (12 aromatics, 10 terpenoids, four nitrogen-containing compounds, and 15 unknown compounds, Appendix 1). The main compounds (> 5% in any of samples) were (R)-Linalool, Methyl p -anisate, Methyl salicylate, Methyl benzoate, and Methyl (E)-cinnamate ( Appendix 1). Three thereof (( R)-Linalool, Methyl p -anisate, Methyl (E)-cinnamate) are reported for the first time as part of the floral bouquet in a member of Spathiphyllum ( Hentrich et al. 2010, Díaz Jiménez et al. 2019, 2021b). In the morning, when the scent is most intense, the spadices of S. maldonadianum are visited by male euglossine bees ( Euglossa sp. ; Fig. 3A ) and stingless bees ( Plebeia sp. ; Fig. 3B ).

Eponymy: —The species is named in honor of the Mexican botanist, M.C. Francisco Maldonado Mares, who died on December 6, 2017. The “Magister”, as he was affectionately named, was a professor of botany at the Universidad Juarez Autónoma de Tabasco where he was always eager to support his students. Among his publications we can find the “Frutales Tropicales de Tabasco ”, “Cercos Vivos de Tabasco ”, and “Plantas Medicinales de Tabasco ”.

Additional specimens examined (paratypes):— MEXICO. Tabasco: Mun. Tacotalpa: Ejido Lázaro Cárdenas, 12 May 80, C . Cowan 2989 ( CSAT!); 0.2 km abajo ( NW) de, y antes de entrar a Tapijulapa. Hasta 0.5 km arriba del camino por el arroyo a pie, 17°28’N, 92°46’W, 43 m, 30 May 1982, C. P . Cowan et al. 3531 ( CSAT!); A 1 km al NE del ejido Xicotencatl, ladera exposición W . Sierra Poaná, 22 May 1985, E. S . López-Hernández 153 ( UJAT!); A 3 km después de Tapijulapa por el camino a la Provincia, 28 Jun. 1985, E. S . López-Hernández 273 ( UJAT!); Selva cuesta chica, 10 Jun. 2004, N. H . García 19 ( UJAT!); ejido Agua Blanca , 31 Mar. 2004, N. H . García & S. G . Ramírez H . 31 (UJAT!); R/ a. Madrigal 5a. Secc., Sierra el Madrigal, 17°30’N, 92°49’W, 200 m, 23 Mar. 2009, P . Díaz Jiménez & A. M . de la Cruz López 726 ( MO!, UJAT!); ejido Pomoquita , 17°22’N, 92°43’W, 109 m, 05 Jun. 2021, P . Díaz Jiménez & P. A . Aguilar-Rodríguez 1582 ( UJAT!); ejido Pomoquita , 17°22’N, 92°43’W, 109 m, 23 Jul. 2021, P . Díaz Jiménez 1586 ( UJAT!) . Mun. Teapa: parte W del cerro El Madrigal, 16 May 1981, G . Ramos et al. 699 ( UJAT!); A 2 km del ejido Sta. Rosa hacia el ejido Lázaro Cárdenas, 17°32’N, 92°08’W, 40 – 50 m, 25 Feb. 1983, M. A . Magaña et al. 1020 ( CSAT!, MO, UJAT!); Cerro del Madrigal, arriba del Centro Puyacatengo, Chapingo , al lado del Río Puyacatengo , 3 km de la carretera Teapa-Tacotalpa , 17°31’N, 92°55’W, 330 m, 18 Jun. 1983, C. P . Cowan et al. 3968 ( MO!); 7 km SE of Teapa on road to Tacotalpa; Rancho San Eneas , Sierra el Madrigal, 17°35’N, 92°50’W, 70 m, 30 Sep. 1986, B. E . Hammel & M . Merello 15522 ( MO!); Vicinity of Teapa, along road between Teapa and Tacotalpa , 3.1 m; E of Teapa , ca. 0.25 miles S of Highway, 17°33’N, 92°58’W, 150 m, 19 Feb. 1987, T. B . Croat & D. P . Hannon 65372 ( MO!); San José Puyacatengo , evergreen tropical forest, 17°31’N, 92°55’W, 188 m, 14 May 2008, P . Díaz Jiménez 539 ( MO!); Sierra el Madrigal, San José Puyacatengo , 17°31’N, 92°55’W, 237 m, 28 May 2008, P . Díaz Jiménez 562 ( XAL!) .

Notes: — Spathiphyllum maldonadianum represents the thirteenth species of the genus Spathiphyllum for Mexico, and the fourth species of Araceae recently described for Tabasco ( Croat et al. 2019, Díaz Jiménez et al. 2020, PérezFarrera et al. 2022). All specimens collected in the type locality of S. maldonadianum and its surroundings, Sierra del Madrigal between Teapa-Tacotalpa, were mistakenly determined and for a long time reported as S. cochlearispathum ( Cowan 1983, Pérez et al. 2005, Díaz Jiménez 2006, Díaz Jiménez et al. 2015, Tropicos 2022). However, unlike the latter, in S. maldonadianum the petiole sheath does not reach the geniculum, its blades are almost twice as wide, its pistils are longer, and have fewer ovules per ovary. Bunting (1965) mentioned that a specimen collected near Teapa and cultivated in a greenhouse, with a light green spathe in anthesis and up to 42 cm long, could represent a new species. That specimen actually corresponds to S. maldonadianum . Furthermore, no specimen from the Sierra del Madrigal was included in his revision under the name of S. cochlearispathum ( Bunting 1960) . The only specimen he included as S. cochlearispathum from Tabasco was S. lacustre Lundell (1941: 4–5) , considered synonymous with that species, but representing a different species than S. cochlearispathum (Díaz Jiménez et al. unpubl.).

Figures

FIGURE 1. Map showing the collection sites of Spathiphyllum maldonadianum (red dots) and S. wilfridianum (red triangle) in the state of Tabasco. The floral scent of S. maldonadianum was collected in situ in Pomoquita (bottom red dot) and of S. wilfridianum from a cultivated plant in Comalcalco (red star; cultivated individual).

FIGURE 2. Spathiphyllum maldonadianum. A. Adult plant in the understory. B. View of the leaf showing the length of the petiole, the end of the sheath (arrow) away from the geniculum, and the adaxial surface of the blade. C. Immature infructescence. D. Inflorescence showing spathe and spadix in anthesis. E. Pistils. Photos by P. Díaz Jiménez.

FIGURE 3. Visitors to the inflorescences of Spathiphyllum maldonadianum in the male phase. A. Euglossa sp. B. Plebeia sp. Photos by P. Díaz Jiménez.