Scottmoria decurrens Cornejo, 2024

Cornejo, Xavier & Prance, Ghillean T., 2024, Three new species of Scottmoria (Lecythidaceae) from northwestern South America, Phytotaxa 675 (1), pp. 59-68 : 63-65

2. Scottmoria decurrens Cornejo , sp. nov. ( Fig. 2 )

New species of Scottmoria , similar to S. caudiculata (R. Knuth) Cornejo (2024:174, Vargas et al. 2024), however, S. decurrens differs from the latter species by the leaves sessile to subsessile (vs. petiolate), the blades decurrent at base (vs. cuneate to obtuse), ± amplexicaul on rachis of inflorescences at terminal branches (vs. never amplexicaul on rachis of inflorescences), distally with secondary veins openly divergent (vs. strongly arching upwards), and fruits with operculum flat to slightly convex (vs. fruits with operculum broadly convex).

Type: — ECUADOR. Esmeraldas: Bilsa Biological Station, Sendero Rojo , 0°21’ N 79°44’ W, ca. 500 m, 16 Oct 2009 (fl, fr), X. Cornejo & A. Macías 8168 (holotype: NY-01922320!; isotypes: GUAY!, MO-3207164!, QCA!, US-03043602!) .

Tree to 30 m tall and 30 cm DBH, the bark rough, brown, the trunk cylindric to base; the branches divergent. Stems glabrous, lenticellate, the lenticels circular to elliptic. Cataphylls present on very young shoots of terminal leafy branches, soon deciduous, oblong-lanceolate, ca. 0.9 × 0.3 cm, amplexicaul at base, veins inconspicuous. Leaves sessile, amplexicaul on terminal new shoots and on rachis of inflorescences; blades obovate to obovate-elliptic or elliptic, 10–25 × 6–10 cm, chartaceous, glossy on both sides, with abundant black punctations abaxially, the base obtuse to rounded, the basal tip decurrent and erect adaxially, the margins entire, marginal glands present in young leaves, turning dark-brown dots in mature leaves, the apex usually caudate, few times narrowly acuminate; venation brochidodromous throughout the blade or eucamptodromous towards base and brochidodromous towards apex, the midrib impressed and canaliculate (dry) adaxially, prominent and with dark-brown glandular dots abaxially, glabrous, the secondary veins in [10–]12–18 pairs, impressed to prominulous adaxially, prominent abaxially, the tertiary veins reticulate. Inflorescences ramiflorous, a short raceme, the rachis 0.2–2.5 cm long on leafy branches, up to 9 cm long in older leafless branches, straight to slightly flexuose, glabrous, lenticellate; pedicels 1–4 × ca. 1 mm, lenticellate, glabrous, green (fresh), blackish (dry); floral bracts 2, triangular to deltoid, 0.7–1 mm long, persistent at post anthesis; flower buds purple-red (fresh). Flowers 5.5–6 cm diam. (fresh), ca. 5–6 cm diam. (dry); calyx with 6 lobes, the lobes triangular to ovate-triangular or deltoid, 2–3 × 2.5–4 mm (fresh), broadly divergent to patent at anthesis, green to maroon, smooth and lenticellate (fresh) abaxially, the bases valvate, arising from fused calyx rim; petals subobovate to ± oblongoid or ovate, (1.8–)2.5–3.5 × (1.6–) 1.8–2.8 cm, pink to pink-red, some petals with margin shortly ciliolate; androecial hood with three coils, 2–2.5 cm across, pale yellow to bright pink (fresh), inner cleft present; vestigial stamens on outside of coils; staminal ring with ca. 200 stamens, the filaments 2–2.5 mm long (fresh), clavate, the anthers ca. 0.5 mm long (fresh); hypanthium glabrous, truncate at summit, tapering at base, 3–5 mm long to articulation; the ovary summit slightly raised over hypanthium, surrounded by a prominent intra staminal ring scar, ca. 0.3 mm high, with a shallow circular depression between intra staminal ring scar and summit of ovary; the style arising ca. 2 × 1.5 mm, stout, distinguished from summit ovary, the stylar collar absent, the stigma pore transversely linear-oblong. Fruits depressed hemiglobose, 7–14 × 9–11 cm, the calyx lobes slightly prominent in subwoody fruits at maturity, the infra-calycine zone half to almost full length of fruit, broadly convex from calycine ring to pedicel, the supra-calycine zone ca. 1–1.5 cm wide, somewhat inward, the operculum occupying to one-third of fruit length, flattened to slightly convex, without or with developed umbo, apical pore present, the pericarp brown when dry, ca. 8–15 mm thick. Seeds ca. 6 per fruit, white or cream at maturity, usually wedge-shaped in cross section, the outer surface hemi-spherical, the two sides flat, 3–5 × 2–3.5 cm, the veins impressed on surface of fresh seeds, the testa smooth, the lateral aril Ibeam type, thick, creamish, the thin sarcotesta white, absorbed and remaining at edge of arils and on some veins at maturity.

Discussion: —The decurrent leaf blades of S. decurrens resemble those of S. amplexifolia (S.A. Mori) , known from the Caribbean coast of Central Panama ( Mori et al. 2015), however, S. decurrens differs from the latter species by the higher number of lateral nerves ([10–]12–18 pairs vs. 6–12 pairs), fruits with infracalycine zone distinctively more developed, broadly convex (vs. infracalycine zone ± truncate towards pedicel), seeds with developed, thick lateral arils (vs. seeds with very narrow and inconspicuous otherwise absent lateral arils), and the pattern of distribution, that is on western Colombia to NW Ecuador (vs. Caribbean coast of Central Panama). Scottmoria decurrens resembles S. albomarginata , described above, but for diagnostic differences please see previous discussion of the latter species. In herbarium material, some collections of S. decurrens (e.g. Daly & Acevedo 5140, F) have been previously identified as Eschweilera integrifolia (Ruiz & Pav. ex Miers) R. Knuth (1939: 97 , the homotypic synonym of S. integrifolia (Ruiz & Pav. ex Miers) Cornejo (2024: 174, Vargas et al. 2024); however, six populations of the latter species including that of the type area have been studied in the field by the author in three provinces of coastal Ecuador, and S. integrifolia does not produce leaves with decurrent, amplexicaul bases, and the fruit at maturity is conspicuously smaller, 5–6 cm diam., green, coriaceous (vs. 9–10 cm. diam., brown, subwoody, in S. decurrens ).

Etymology: —The epithet decurrens refers to the decurrent base of leaves, that is one of the main characters of this species, that for several years had been noticed by Scott Mori (comm. pers. to Cornejo).

Common names: — Colombia: Guascapedo (Prehispanic indigenous name?, Monsalve 166). Ecuador: Tete (Prehispanic indigenous name?, Jativa & Epling 807, US), sabroso (Spanish, Cornejo & Macías 8168, NY, the type).

Habitat and distribution: —An understory to medium size tree of mature wet forests, in well drained soils. Known from northwestern Ecuador to western Colombia, 50 to 1200 m elevation.

Phenology: — Flowers have been observed from June to December, fruits from August to January. Flowers are produced simultaneously or immediately after growing new shoots with cataphylls and leaves.

Conservation status: —Based on herbaria georeferenced collections the extent of occurrence of Scottmoria decurrens is of less than 20.000 km 2, therefore, the IUCN conservation status assigned to this species is Vulnerable, VU B1 ( IUCN, 2022).

Paratypes: — COLOMBIA. Nariño: Municipio de Barbacoas, corregimiento de Altaquer, vereda El Barro, Reserva Natural Río Ñambí, sendero paralelo al río Ñambí, cerca de la desembocadura del río Espingo, 01°17’28¨N 78°05’49¨W, ca. 1200 m, 21–22 December 2003 (fl), N. Salinas, J. Betancur, J. Pérez 388 (NY!). Valle del Cauca: Bajo Calima; Concesión Pulpapel, Buenaventura, bosque pluvial tropical, 3°55’ N 77°00’ W, 100 m, 9 August 1984 (fr), M. Monsalve 166 (COL, F!, MO); road to Juanchaco Palmeras, pluvial forest, 3°55’ N 77°02’ W, 50 m, 19 July 1984 (young fr), A. Gentry, M. Monsalve, H. Mazuero 48364 (COL!, MO). ECUADOR. Carchi: Reserva Indígena Awá, comunidad San Marcos, 25 km al NW de El Chical, bosque pluvial premontano, 1°06’ N 78°14’ W, 1500 m, 16–30 November 1990 (fl), D. Rubio, C. Quelal, J. Pai 1065 (AAU!). Esmeraldas: Ventanas, km 319 on Quito-San Lorenzo road, ca. 100 m, 16 July 1964 (fl), C. Jativa & C. Epling 807 ( US!). Bilsa Biological Station, Mache mountains, 35 km W of Quinindé, 0°21’ N 79°44’ W, 500 m, 1 October 1996 (fl), J. L. Clark 2968 (COL!, NY!, US!); ibidem, collected on Ramón Loor´s property, 23 October 1996 (fr), J. L. Clark 3095 ( US!). Mun. Lita, Río Lita and tributaries (affluent of Río Mira), ca. 120 km NW Ibarra, ca. 14 km WNW of Lita, 0°52’ N 78°29’ W, ca. 600 m, 7 May 1987 (fr), D. C. Daly, P. Acevedo 5140 (F!). Manabí: Cerro Pata de Pájaro, 10 km E of Pedernales, finca of the family Arroyo , 1°00’N 79°58’W, 300–700 m, 19–21 June 1996 (fl), J. L. Clark, E. Arroyo , P. Hibbs 2667 (NY!).

Figures

FIGURE 2. Scottmoria decurrens. A. Terminal new shoot arising from the amplexicaul leaf base, lateral view; B. Glossy leaf blade, abaxial view; on both corner squares: young inflorescences clasped by sessile amplexicaule leaf bases; C. Terminal leafy branch with three axillary inflorescences; upper right: longitudinally sectioned androecial hood exhibiting a triple coil, lateral view; two calyces at post-anthesis, lateral and adaxial view; D. Subsessile fruit attached to a sessile leaf base, lateral view; E. Fruit at maturity showing seeds and cream color arils, the operculum removed, adaxial view (A–C, E, based on Cornejo & Macías 8168, the type; D from unvouchered specimen). Photos A–C, E by Xavier Cornejo; photo D by Nicolás Mejía-Pazos.