Guatteria sanjorgense Villanueva & Parra-Liz., sp. nov.
Creators: name: Villanueva-Tamayo, Boris
name: Parra-Lizcano, Nicolas
name: Rios-Cervera, Jorge Enrique
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Magnoliales
Annonaceae
Guatteria
Guatteria sanjorgense

description: Guatteria sanjorgense Villanueva & Parra-Liz., sp. nov. (Figs. 1,2,3)
TYPE:— COLOMBIA. Tolima: Ibagué, carretera a Calambeo, Jardín Botánico San Jorge, 4º27’19’’N; 75º13’04’’W, 1280 m, 15 March 2023 (fl), N. Parra-Lizcano & J. Ríos-Cervera 107 (holotype: TOLI! [accession 32337]); isotypes: COL, CUVC, HUA, JBB). Figures 1 and 2.
Diagnosis:— Guatteria sanjorgense resembles Guatteria alleni R.E. Fries (1950: 336) and G. goudotiana, but it can be differentiated from these two species by having fruits with 5–12 unusually globose monocarps on stipes <14 mm long, petals light reddish when mature (in vivo), sparse appressed hairs on both sides (vs. sparsely covered with appressed and erect hairs to glabrous above in G. alleni, and glabrous above and sparsely covered with appressed, brown hairs to glabrous below in G. goudotiana), and leaves with non-revolute bases (vs. with revolute bases in G. goudotiana).
Trees 11–18 m tall, up to 12 cm dbh; trunk cylindrical, sympodial branching; young twigs sparsely covered with appressed hairs. Leaves with petioles 5–6 × ca. 2 mm, channeled adaxially, rounded abaxially, dark green when fresh, black when dry, with appressed hairs to glabrescent, blades 15–20 × 4–6 cm, 3.3 to 3.7 times longer than broad, narrowly elliptic, papyraceous, non-scabrous, apex acuminate, acumen 1–2 cm long, base acute to attenuate, non-revolute, midrib impressed adaxially, raised abaxially, sparsely covered with appressed hairs adaxially and moderately covered with appressed hairs abaxially, lateral veins 13–15 per side, brochidodromous, joining 2–3 mm from the margin, impressed to flat above, raised and with appressed hairs below; tertiary venation conspicuous abaxially. Flowers mostly solitary or sometimes in axillary 2-flowered inflorescences, flowering and fruiting pedicels 1–1.7 × ca. 0.2 cm, green, covered by brown hairs, articulated 3–6 mm above the base, densely covered by appressed hairs; bracts 2–3, soon falling, flower with a sweet banana smell when mature, buds rounded or obovate; sepals 3, 5–6 × 7–8 mm, ovate-triangular, reflexed, covered by appressed hairs on both sides, particularly towards the base; petals 6, 1.9–3 × 0.7–1.5 cm, oblong-ovate, green, light reddish when mature in vivo, with densely appressed hairs (towards base) abaxially, glabrous adaxially; stamens 180–200, ca. 1.6 mm long, yellow in vivo, connective shield glabrous; carpels ca. 3 mm long, dark brown in sicco, covered with appressed hairs, carpels 28–31, narrowed into a style, stigma obovoid, ovule 1, basal. Monocarps 5–12, ca. 2 × 1.5 cm, globose, glabrous, stipitate, stipes ca. 14 mm long, glabrous, monocarps and stipes green, turning dark violet when mature in vivo. Seeds 0.8–0.9 × 0.6–0.7 cm, ellipsoid, 1 per monocarp, dark brown; pitted with a raised transverse line (raphe) ca. 1.7 mm wide.
Phenology: This species was collected with flowers in January, and with an abundant number of flowers and fruits in March.
Etymology: Guatteria sanjorgense is named after San Jorge de Ibague Botanical Garden, the only place where this species has been found.
Common names: Cargadero.
Distribution and ecology: The new species is known to occur in wet montane forest fragments protected in the San Jorge Botanical Garden, which is located in the Eastern slopes of the Central Colombian Cordillera (Figure 3). This region harbors the protected mountain ecosystems that surround Ibague city. The new species was found during fieldwork to set up four permanent plots of 0.25 ha and sample all individuals with DBH greater than 10 cm. The individuals of this new species reach 18 m tall and are distributed in different sectors of the garden, associated with slopes between 30% and 40%. The population density is low, with only four individuals sampled in a total of 543 trees. These forests are dominated by Ladenbergia oblongifolia (Humboldt ex Mutis) Andersson (1994: 19), Olmedia aspera Ruiz & Pavon (1798: 257), and Inga marginata Willdenow (1806: 1015).
Additional specimens examined:— COLOMBIA. Tolima: Ibagué. Relictos de bosques del Jardín Botánico San Jorge, 1270 m, 4°27’21.33’’N, 75°13’12.62’’W, 10 October 2020 (fl, fr) B. Villanueva et al. 5693 (JAUM!, JBB!, TOLI!); Relictos de bosques del Jardín Botánico San Jorge, parcela de carbono No. 2, 1367 m, 4°27.418’N, 75°12.985’W, 19 February 2021 (fl), B. Villanueva et al. 6166 (JBB!, LAMUA!); idem, parcela 4, individuo marcado 4°27’14.382’’N, 75°13’10.099’’W, 4 March 2022 (fl, fr), D.A. Caballero & H. Oyuela 418 (COL!, JBB!, TOLI!); idem, por el sendero en el descanso de la Y, 1337 m, 4°27’27.802’’N, 75°13’10.923’’W, 15 March 2023 (fl), N. Parra & J. Rios 108 (TOLI!).
Preliminary conservation status: Guatteria sanjorgense has a severely limited geographic range, occupying an area of less than 20 km ², and is subjected to significant anthropogenic pressures that threaten its habitat integrity and sustainability (Criterion B1). The single known population of G. sanjorgense is small, with fewer than 30 individuals observed (Criterion D). Furthermore, this species faces a high risk of population size reduction, both currently and in the foreseeable future, due to habitat fragmentation and ongoing environmental degradation (Criterion A). The combination of a limited geographic range, small population size, and intense anthropogenic pressure supports its classification under multiple criteria, suggesting that G. sanjorgense should be treated as Critically Endangered under IUCN criteria B1ab(iii), C2a(ii), and D.
Notes:— This new species is morphologically similar to five other taxa, which are presented in Table 1: Guatteria allenii R.E. Fries (1952: 336), G. dolichopoda Donn. Sm. (1897: 2), G. goudotiana, G. rufotomentosa and G. punctata. Nonetheless, G. sanjorgense is primarily distinguished from these species by the following character combination: 5 to 12 globose monocarps, flowers with light reddish petals, and leaves without erect hairs. See Table 1, based on Maas et al. 2015, for details on how to distinguish these six species.
The identification key below can be used to identify species of Guatteria that occur in the Colombian department of Tolima.
description: Published as part of Villanueva-Tamayo, Boris, Parra-Lizcano, Nicolas & Rios-Cervera, Jorge Enrique, 2024, A new species of Guatteria (Annonaceae) from the Andean mountain forest of Colombia, pp. 271-279 in Phytotaxa 658 (3) on pages 272-273, DOI: 10.11646/phytotaxa.658.3.5, http://zenodo.org/record/13217720