Amphitecna fonceti Ortiz-Rodr. & Gomez-Dominguez, 2021

Gomez-Dominguez, Hector, Ortiz-Rodriguez, Andres Ernesto, Velasco-Espino, Delfilia & Hernandez-Burguete, Rene, 2021, Taxonomic updates in Amphitecna (Bignoniaceae): A new Mexican species and the re-establishment of the giant-leaved A. megalophylla, PhytoKeys 171, pp. 75-90 : 75

Amphitecna fonceti Ortiz-Rodr. & Gomez-Dominguez sp. nov. Figures 2 , 3

Type.

Mexico. Chiapas, Municipio de La Concordia, Área de Protección de Recursos Naturales La Fraylesca, Rancho “Pacayal” a 3 kilómetros del ejido Solo Dios,1441 m, 15°46'57.7"N, 92°59'04.6"W, 24 May 2020(fl, fr) Gómez- Domínguez H. y Hernández-Burguete R. 3840 (holotype HEM; isotypes: MEXU, MO).

Diagnosis.

Amphitecna fonceti is distinguishable from the other species of Amphitecna by its ramiflorous inflorescences that bear multiple flowers per shoot, buds rounded at apex, large flowers with a transverse fold in the corolla throat, calyx surface pubescent and strongly costate, and fruits elliptic, apiculate at the apex. Amphitecna fonceti is morphologically similar to A. apiculata and A. latifolia , both of which occur in Mexico. However, A. apiculata differs by the small and tubular corollas, and by the calyx with a smooth and glabrous surface. Amphitecna latifolia , on the other hand, differs by the smaller leaves, smooth and glabrous calyx surface, and globose fruits with a rounded apex. The three species show different climatic preferences (Table 3 ).

Description.

Small to medium sized trees, 3-9 m alt., 6-25 cm DBH, the secondary branches terete. Leaves alternate-verticillate, clustered near the apex of branches, olive-green when dry, glabrous, coriaceous, 13-35 cm long × 6-13.2 cm wide, oblanceolate to obovate, short acuminate, acute to attenuate basis, midrib slightly raised on the upper surface, prominent on the lower surface; secondary veins 10-20 on each side, slightly raised above, prominent below; petiole shorter than 1 cm long, merging with attenuate leaf base, red wine in vivo. Inflorescences bearing three to six flowers (rarely with a single flower), borne on leafless portions of old branches, rarely terminal or along the main trunk (cauliflory), with a sour-odor; pedicels, outer side of buds, and calyces pubescent and densely covered with lenticel-like white dots. Flowers more or less erect, not pendant, pedicel 38-60 mm long; buds, rounded at apex; calyx campanulate, 25-32 mm long, coriaceous, evenly 2-3 -labiate, strongly costate, with 6-10 longitudinal ridges per lobe; corolla funnelform, with a transverse fold on throat between 22-27 mm from the base, pale green, 38-46 mm long × 20-23 mm wide at the tube mouth, the basal portion of the corolla funnel-shaped, 9-13 mm long, lobes more or less fused into a frilly-margined rim; androecium with stamens 3 or 4, included, inserted 4-12 mm from base of the tube, anther thecae divergent, 5-6 mm long, filaments 12-29 mm long, staminodes shorter than 20 mm long when present, inserted 3-6 mm from base of the tube; gynoecium with ovary ca. 8 mm long × ca. 4 mm wide, broadly elliptic, glandular-papillose, style 25-29 mm long, stigma bifurcate; disc annular-pulvinate, ca. 11 mm in diameter. Fruits elliptic, 110-180 mm long × 70-105 mm wide, acute to short acuminate at apex, rounded to short acuminate at the base.

Habitat and ecology.

This species is known only from the type locality in Chiapas, Mexico. The species inhabits areas with sedimentary soils, mostly formed by sandstones with a thin layer of organic matter, mostly within altered remnants of oak and pine-oak forest. The species with which it coexists are Quercus rugosa Née, Inga vera Willd, Damburneya coriacea (Sw.) Trofimov & Rohwer, Eugenia capuli (Schltdl. & Cham.) Hook. & Arn., Trema micrantha (L.) Blume, Cecropia obtusifolia Bertol., and Coffea arabica L.

Phenology.

Specimens were collected in full bloom or with ripe fruit in April and May. Flower buds were observed in March and ripe fruits in June.

Etymology.

The specific epithet honors FONCET (Fondo de Conservación El Triunfo, A.C.), in recognition of 18 years of funding dedicated to conservation projects in natural protected areas within the Sierra Madre de Chiapas, Mexico.

Conservation status.

According to the IUCN (2019), this species is considered as Critically Endangered [CR B1ab (iii)]. Its area of occupancy (AOO) is 8.0 km2 and the extent of occurrence (EOO) is 0.154 km2, showing a restricted distribution. Although the new species is distributed within a protected natural area, the oak, pine-oak forest at the type locality is seriously fragmented, with only small remnants persisting. Amphitecna fonceti is rare, with only 12 individuals being known to date.

Uses.

The indigenous community where A. fonceti is found uses the fruits to treat respiratory diseases. The seeds of ripe fruits are extracted and soaked in a bottle of tequila for a week, after which a small glass is drunk in the morning to treat asthma. For whooping cough, two tablespoons of honey and almond oil are poured into the fruit after the removal of the fruit tip. The fruit is then cooked in water bath and its interior used as syrup. Its medicinal use likely helps the maintenance of this species within local coffee plantations.

Additional specimens examined.

Mexico. Chiapas, La Concordia: Área de Protección de Recursos Naturales, La Fraylesca; Rancho Pacayal a 3 kilómetros del ejido Solo Dios, 15°46'54.9"N, 92°59'04.8"W, 1359 m., 24 de Mayo de 2020., Gómez- Domínguez, H. and Hernández-Burguete, R. 3841 (HEM); same locality, Gómez- Domínguez, H. and Hernández-Burguete, R. 3842 (HEM); Gómez- Domínguez, H., Velazco Espino, D. and Hernández-Burguete, R. 3841 (XAL).

Notes.

In addition to A. apiculata and A. latifolia , A. fonceti can also be confused with A. sessilifolia , another species from the A. molinae group. However, A. sessilifolia (endemic to Costa Rica) shows terminal flowers, larger corollas, stamens inserted 13-18 mm from base of the corolla tube, larger pistils, smooth and glabrous calyces ( Gentry 1980, Table 3 ). Amphitecna sessilifolia has been incorrectly reported to Mexico ( Martínez-Meléndez et al. 2017) based on misidentified specimens of A. breedlovei (e.g., Faustino Miranda 6916, MEXU-67682), A. latifolia (e.g., G. Martínez C. 2294, MEXU-733205), and A. tuxtlensis (e.g., J.I. Calzada 1457, MEXU-309621).

Amphitecna megalophylla resurrected

Our results indicate that A. megalophylla is best treated as a separate taxon that can be identified by the following features: pachycaul trees, with leaves up to 1 m long, multi-flowered inflorescences, cauliflorous and long-pedicellate flowers with a transverse fold in the corolla throat, and fruits with costate/angulate surfaces. The following species is thus treated as an accepted taxon here:

Figures

Figure 2. Vegetative features of Amphitecna fonceti sp. nov. A habit B phyllotaxy C adaxial side of leaf D abaxial side of leaf. Photographs by Hector Gomez Dominguez.

Figure 3. Reproductive features of Amphitecna fonceti sp. nov. A ramiflorous inflorescences with several flowers per shoot B corolla mouth C strongly costate calyx D corolla showing three stamens E corolla showing the transverse fold in the throat F flower developmental stages, from bud to anthesis G fruit shape variation. Photographs by Hector Gomez Dominguez.