Ternstroemia amistadensis Q. Jiménez & D. Santam., 2015

Aguilar, D. Santamaría, Jiménez-Madrigal, Q. & Monro, A. K., 2015, A new species of Ternstroemia (Pentaphylacaceae) from La Amistad Binational Park and World Heritage Property, Costa Rica and Panama, Phytotaxa 217 (1), pp. 87-91 : 88-90

Ternstroemia amistadensis Q. Jiménez & D. Santam. , sp. nov. ( Fig. 1 , 2 )

Ternstroemia amistadensis is most similar to the Peruvian T. pachytrocha Kobuski (1942: 320) with which it shares black punctations on the lower leaf surface, glandular-denticulate bracteoles, bilocular ovaries and undivided styles. Ternstroemia amistadensis may be distinguished from T. pachytrocha by the former’s larger and obovate leaf laminae with more conspicuous nervation on both surfaces, ovoid fruit with thinner pericarp and smaller seeds that are fewer per fruit.

Type:— COSTA RICA. Limón, Z. P. Río Banano. Cuenca del Estrella. Valle de la Estrella, Fila Matama. Cerca de 11 km SW del pueblo de Aguas Zarcas. Punto 10 C. Bosque con predominio de árboles de Drimys , Oreopanax ; sotobosque con Piper , Geonoma , Miconia , 09º47 ′ 49 ″ N, 83º09 ′ 43 ″ W, 1400–1500 m, 29 Oct 2007 (fruit), D. Santamaría, D. Solano, M. Moraga, C. Godínez & A. Rodríguez 6706 (holotype: INB; isotypes: BM, CR, F, GH, K, MO, NY, PMA).

Small tree, 5–8 m, the slash reddish; twigs cylindrical, subopposite or verticillate, glabrous. Leaves spirally arranged and clustered toward the branch tips, petiolate; petioles 0.3–1.0 cm, adaxially flattened, glabrous; laminae 5.5–11 × 2.4–7.1 cm, obovate, coriaceous, glabrous on both surfaces; midrib weakly sunken on the upper surface, prominent and rounded on the lower surface; lateral nerves 4–6 pairs, borne at 45–60° to the midrib, weakly sunken on both surfaces; lower surface with black punctuations visible to the naked eye, ca. 0.3 mm, ± crateriform; upper surface prominently papilose-tuberculate, ca. 0.1 mm; base cuneate, occasionally obtuse; margin entire, somewhat revolute; apex obtuse to occasionally rounded (sometimes emarginate). Flowers axillary, bracteate, solitary, bisexual; pedicel 10–35 mm long, thick 2–3 mm at apex, straight to weakly curved; bracteoles 2, borne opposite or subopposite the base of the calyx, unequal, 2–3 × 3–5 mm, ‘D’-shaped, both inner and outer surface glabrous; outer surface rugose, the margins sparsely glandular-denticulate; apices apiculate or rounded; sepals 5, lobed; lobes imbricate in 2 whorls; external whorl of lobes 7–10 × 8–10 mm in flowers (in fruits 8–11 × 10–12 mm), broadly ovate broadly ovate to very broadly ovate; internal whorl of lobes 7–10 × 7–9.5 (–12) mm in flowers (in fruit 11–14 × 9–10 mm), broadly ovate; inner and outer surfaces glabrous; outer surface granular-rugose; margins entire, membranous, brown, rarely inconspicuously glandular-denticulate toward the base (external whorl), the apices rounded; petals 5, 6–9 × 4 mm, reported as white, fused for the basal ca. 4 mm, ovate; margin entire; apex rounded or acute; stamens ca 43–55; filaments 0.5–2 mm, ± biseriate, free from the petals and separate from each other; anthers 0.5–1.1 mm, the connective extending 1–1.3 mm long; ovary 4 × 3.5 mm, round and complanate with 2 locules, each bearing 8–11 ovules. Immature(?) fruit 1.3–2.3 × 1–1.5 cm, spherical to ovoid, brownish-green; pericarp 0.2–0.3 cm thick; style persistent, 0.1–0.3 cm, straight or weakly curved; seeds 3 or 4 by fruit, ca 15 × 7–9 mm, the sarcotesta purple in fresh material, brown in herbarium material.

Etymology:— Ternstroemia amistadensis is named after the La Amistad Binational Park and World Heritage Property, the only known localities.

Phenology:— Flowering material of Ternstroemia amistadensis has been collected in March, April and August and fruiting material between August and October. The area is relatively unseasonal but has variable short dry seasons of 2–4 weeks in February-March and a shorter dry period in August.

Distribution and habitat:— Ternstroemia amistadensis is known only from the Caribbean slopes of La Amistad Binational Park, Costa Rica and Panama. Here it has been recorded in semi-open areas and edges of wet evergreen forest and cloud forest at elevations of 1050–1700 m with an Extent of Occurrence of ca 14,000 km 2 and associated with Drimys granadensis L. f. ( Winteraceae ), Oreopanax sp. ( Araliaceae ) and forest understory characterised by Piper sp. ( Piperaceae ), Geonoma sp. ( Arecaceae ) and Miconia sp. ( Melastomataceae ).

Conservation status:— Using IUCN criteria (IUCN 2001), Ternstroemia amistadensis is considered Near Threatened (NT). Ternstroemia amistadensis has an Extent of Occurrence of 14,000 km 2 (IUCN criteria B1 <20,000 km 2) and is known from only six localities (IUCN criteria Ba, number of locations ≤ 10). At these localities, the populations of this species comprise a few mature individuals. The majority of the Extent of Occurrence for the species occurs within the La Amistad Binational Park. Whilst this is part of a UNESCO World Heritage site, the forest has been impacted by encroachment from cattle ranching, illegal mining exploration and the construction of a number of hydroelectric stations around the Park’s periphery. We suggest that this meets IUCN criteria Bb(iii) of ‘continuing decline in area, extent and/or quality of habitat’ (IUCN 2001). Using the IUCN methodology, our Global Conservation Assessment for Ternstroemia amistadensis is classed as Vulnerable (VU) based on criteria B1 Ba and Bb(iii). Given that much of the Extent of Occurrence has been poorly explored, we have revised this classification to Near Threatened (NT).

Discussion: Ternstroemia amistadensis can be distinguished from other Mesoamerican Ternstroemia species by its coriaceous obovate leaf laminae with obtuse to rounded and occasionally emarginate apices, shiny upper surfaces, black-punctate lower surfaces, conspicuous lateral nerves in dried material and large granular-rugose sepals. T. amistadensis is most similar to T. pachytrocha from Peru and T. macrocarpa Triana & Planchon (1862: 269) from Colombia and Ecuador, which both share with T. amistadensis the characters of a 2-locular ovary, entire style and relatively large fruit. Ternstroemia amistadensis may be distinguished from T. pachytrocha and T. macrocarpa on the basis of leaf, petiole, pedicel and fruit morphology as summarised in Table 1. In the Theaceae treatment ( Jiménez 2015) for the Manual de Plantas de Costa Rica T. amistadensis was treated as Ternstroemia . “sp. A”.

Additional specimens examined:— COSTA RICA. Limón: Cantón de Limón. Zona Protectora Río Banano, cuenca del Banano , Valle de la Estrella , Fila Matama , ca. 11 km SW del pueblo de Aguas Zarcas, 09º48’06 ″ N, 83º09’57 ″ W, 1400–1500 m, 29 Oct 2007 (but fl., fr.), D. Solano et al. 4799 ( BM, CR, GH, INB, MO) ; Cantón de Limón. Matama, El Progreso. Cabeceras del Río Cariei , Fila Matama , 09º47’20 ″ N, 83º08’18 ″ W, 1400 m, 27 Apr 1989 (fl.), G. Herrera & A. Chacón 2817 ( INB, BM, CR, GH, MO) Cantón de Talamanca. Bratsi , Amubri, Alto Lari, Kivut, afluente innominado del Río Lari , margen izquierda, 09º22’50 ″ N, 83º05’10 ″ W, 1500 m, 21 Mar 1992 (fl.), G. Herrera 5414 ( BM, CR, GH, INB, MO, US) ; Cantón de Talamanca. Bratsi. Talamanca, Bratsi, Fila de exploración minera entre Río Sukut y Río Carbri. Cerro Schtomat, 09º22’12”N, 82º56’24”W, 1050 m, 13 Jul 1989 (fl.), G. Herrera 3266 ( INB, CR) . PANAMA. Bocas del Toro: Changuinola, Parque Internacional La Amistad, Falso Fábrega , 09º09’59.0’’N, 82º39’21.3’’W, 1700 m, 6 Aug 2008 (fr.), D. Solano et al. 5721 ( INB, MO) .

Figures

FIGURE 1. Ternstroemia amistadensis Q. Jiménez & D. Santam.:A, fertile branch with fruit, with enlarged view of lower leaf surface with black punctations. B, flower bud. C, immature fruit, with an insertion highlighting the unequal bracteoles borne opposite or subopposite the base of the calyx. D, mature fruit, with section cleared to reveal seeds. E, seeds. Illustration based on images of living material and herbarium specimens of Santamaría 6706 (INB).

FIGURE 2. Living material of Ternstroemia amistadensis Q. Jiménez & D. Santam.: A, leafy branch, showing lower surface of leaves with dark punctations. B, decomposed fruit and sepals. C, mature fruit. Images are of living material (prior to pressing) of Solano et al. 5721 (MO). Photos by Daniel Solano Peralta.