Scottmoria albomarginata Cornejo, 2024

Cornejo, Xavier & Prance, Ghillean T., 2024, Three new species of Scottmoria (Lecythidaceae) from northwestern South America, Phytotaxa 675 (1), pp. 59-68 : 60-63

1. Scottmoria albomarginata Cornejo , sp. nov. ( Fig. 1 )

New species of Scottmoria , similar to S. caudiculata (R. Knuth) Cornejo (2024:174, Vargas et al. 2024), however, S. albomarginata differs from the latter species by the leaves sessile to subsessile (vs. petiolate), the blades decurrent at base (vs. cuneate to obtuse), amplexicaul in new shoots and terminal inflorescences (vs. never amplexicaul), petals with hyaline white margins (vs. petals uniformly rose to purple), fruits with operculum flat to slightly convex (vs. fruits with operculum broadly convex), mature seeds with a receding sarcotesta that is remaining nearby a bright yellow funicular lateral arils (vs. mature seeds with a spreading sarcotesta and snow white, cream or faintly light-yellow funicular lateral aril).

Type: — ECUADOR. Guayas: Las Cumbres , wet forest converted to cropland, remnant native trees scattered or in highly fragmented small patches, 2°22’S 79°15’W, ca. 420 m, 18 May 2024 (fl, fr), X. Cornejo & E. Suárez 10188 (holotype: GUAY!; isotype: QCA!) .

Tree to 12 m tall and 40 cm DBH, the bark longitudinally fissured, brown with white patches, exfoliating in narrow, elongate irregular plaques, the trunk subcylindric to base; the branches divergent. Stems glabrous, lenticellate, the lenticels vertically oriented. Cataphylls present on very young shoots of terminal leafy branches, soon deciduous, oblong-lanceolate, ca. 1–5× 0.5–0.8 cm, amplexicaul at base, veins inconspicuous. Leaves sessile, amplexicaul on terminal new shoots and on rachis of inflorescences; blades elliptic to slightly obovate-elliptic, 10–23.5 × 5–10 cm, chartaceous, glossy on both sides, with abundant black punctations abaxially, the base cuneate to broadly obtuse, the basal tip decurrent and erect adaxially, the margins entire, marginal glands present in young leaves, turning inconspicuous dark-brown dots in mature leaves, the apex usually acuminate; venation brochidodromous throughout the blade or eucamptodromous towards base and brochidodromous towards apex, the midrib impressed and canaliculate (when dry) adaxially, prominent and with dark-brown glandular dots abaxially, glabrous, the secondary veins in (6-)12–15 pairs, impressed to prominulous adaxially, prominent abaxially, the tertiary veins reticulate. Inflorescences ramiflorous on terminal young leafy branches, a short raceme, the rachis 0.2–2 cm long, apparently not produced 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, 1–1.5 mm long, persistent post anthesis; flower buds purple-red (fresh). Flowers 5–6 cm diam. (fresh), ca. 5 cm diam. (dry); calyx with 6 lobes, the lobes triangular to broadly deltoid, 2–3 × 2–4 mm (fresh), patent at anthesis, green, smooth and richly white lenticellate (fresh) abaxially, the bases valvate, arising from fused calyx rim; petals subobovate to ± oblongoid or ovate, (1.8–)2.3–3.5 × 1.5–2.5 cm, purple-red, margins with a hyaline white fringe, some petals with margin shortly ciliolate; androecial hood with three coils, 2.7–3.5 cm across, purple-red (fresh), inner cleft present; vestigial stamens on outside of coils; staminal ring with ca. 200 stamens, the filaments ca. 2 mm long (fresh), clavate, the anthers ca. 0.5 mm long (fresh); hypanthium glabrous, truncate at summit, tapering at base, 5–6 mm long to articulation; the ovary summit slightly raised over hypanthium, surrounded by a plane intra staminal ring scar, shallow depression between ring scar and summit of ovary present; the style arising ca. 1.5 × 1.5 mm, stout, distinguished from summit ovary, the stylar collar absent, the stigma pore transversely linear-oblong. Fruits depressed globose or oblate, 8–12 × 11–12 cm, the calyx lobes minute, upwards, inconspicuous in subwoody fruits at maturity, the infra-calycine zone approximately one third of length of fruit, broadly convex from calycine ring to pedicel, the supra-calycine zone ca. 2 cm wide, straight upwards, the operculum occupying up to one-third of fruit length, broadly convex, without a developed umbo, apical pore present, the pericarp brown when dry, 5–8 mm thick. Seeds 7–10 per fruit, dark brown at maturity, usually wedge-shaped in cross section, the outer surface hemi-spherical, the two sides flat, 5–6 × 2.5–4 cm, the veins rather inconspicuous on surface of fresh seeds, the testa smooth, the lateral aril I-beam type, thick, bright yellow, the thin sarcotesta white, absorbed and remaining at edge of arils at maturity.

Discussion: — Scottmoria albomarginata resembles S. caudiculata but the new species differs from the latter by the characters discussed above in the diagnosis. The decurrent leaf base of sessile leaves of S. albomarginata resembles S. decurrens Cornejo , described below from northwestern Ecuador to western Colombia, and also S. amplexifolia (S. A. Mori) Cornejo (2024: 172, Vargas et al. 2024) from the Caribbean coast of Central Panama ( Mori et al. 2015). However, S. albomarginata is quite distinct from all other species in the genus and can be easily recognized by the flowers with a hyaline white marginal fringe in all the petals, and the large androecial hood, 2.7–3.5 cm across, the latter most likely an adaptation to pollination by large bees. Furthermore, Scottmoria albomarginata also differs from S. amplexifolia by the fruits with infracalycine zone distinctively more developed, as wide as the fruit diameter, and broadly convex (vs. infracalycine zone less developed, narrower than fruit diameter, ± truncate towards pedicel). As in most of Neotropical Eschweilera and Lecythis Loefl. (1758: 189) , during herborization process, as a result of high temperature the flowers turn darker to blackish, loosing their original fresh colors, and the soft tissues of corollas tend to shrink, therefore, those characters cannot be observed and these species may not be easy to differentiate in dry herbarium material, however, they are conspicuously evident to define this as a distinctive species when observed in vivo. This study of these three new species emphasizes the importance of observations on living plants in the field to accurately determine the relationships of the species.

Etymology: —The epithet albomarginata that in Latin means white margined refers to the hyaline white marginal fringe that is present in all petals of this species, which is an unusual feature in Scottmoria and in the closely related Neotropical genera Eschweilera and Chytroma Miers (1874: 229) .

Common names: —Camarón (Spanish), sabroso (Spanish, both names from Cornejo & Suárez 10186, GUAY, the type). The name camarón that in English means shrimp, refers to the analogy of the curved androphore of S. albomarginata that is a common feature in all Scottmoria as well as in other related genera such as Eschweilera and Chytroma , suggesting a similarity with the curved tail of a shrimp. It is said in the field that the name sabroso that in Spanish means delicious refers to the fact that the aril of seeds of this species is very palatable and highly attractive to rodents such as agoutis and pacas. Both vernacular names are commonly applied to several species of Scottmoria in western Ecuador.

Habitat and distribution: —An understory to medium size tree, persistent as a solitary individual surrounded by crops or in small fragmented patches of disturbed wet forest, in well drained soils. Known only from type locality in evergreen western Andean foothills, in the province of Guayas, ca. 420 m elevation.

Phenology: — Flowers and fruits have been observed in May, fruits from May to June (July?). Flowers are produced simultaneously or immediately after growing new shoots with cataphylls and leaves. No flower visitors have been observed in the field, however, it is expected that the flowers of this and those of the remaining two new species of Scottmoria presented in this article are visited and pollinated by native bees.

Conservation status: —This species is uncommon in Las Cumbres, where only two trees have been found persisting in very disturbed and fragmented habitats. Based on the very small area of occurrence in an area of only 1 km 2, and its persistence in a single locality that is under pressure by forest fragmentation and massive conversion to crops, Scottmoria albomarginata is assigned here a provisional category of Critically Endangered (CR B2 a, b), following the criteria of IUCN (2022). From a fruit of the type collection, seven seeds of Scottmoria albomarginata were taken by the senior author and planted under shade in the city of Guayaquil, in a distinctively warmer locality with a temperature at least ca. 5° C higher than that of the type locality. All seven planted seeds germinated during a period of between 2 to 4 months, six of them under shade in the patio of a house and one within the GUAY herbarium office all in distinctively warmer conditions. As similar germination experiments have been successfully achieved by the author for several species of Couroupita , Gustavia and Grias ( Lecythidaceae ), from which, fruits and seeds have been collected in wet forests from several localities and from both sides of Andes in Ecuador and also planted in Guayaquil, these results suggest that deforestation, forest fragmentation, land use conversion, and uncontrolled expansion of the agricultural frontier, could be more dangerous than global warming, at least for Lecythidaceae in Ecuador. This indicates that greater efforts must be addressed to decrease the deforestation rate and to achieve an effective conservation of native forests.

Paratypes: — ECUADOR. Guayas: Las Cumbres, 2°22’S 79°15’W, ca. 420 m, 18 May 2024 (fl), X. Cornejo

10186 (GUAY!, QCA!).

Figures

FIGURE 1. Scottmoria albomarginata.A. Terminal new shoot arising from the amplexicaul leaf base, note the cataphyll and two inrolled young leaves, lateral view; B. Terminal lenticellate branch holding a sessile leaf base, lateral-abaxial view; upper left corner: longitudinal section of androecial hood displaying a triple coil, lateral view; C. Flower at maturity, two flower buds and a calyx at post-anthesis; D. Eight androecial hoods, note the size; upper right: valvate calyx and glossy hypanthium, lateral-abaxial view; E. Two fruits at maturity and a removed operculum, note the 10 seeds and yellow arils, the glossy leaves at bottom; F. Mature smooth dark brown seed with I-beam yellow aril and creamish sarcotesta remains in between (A–F, based on Cornejo & Suárez 10186, the type). Photos by Xavier Cornejo.