Myrcia maculata M.F.Santos

Santos, Matheus F., 2025, Taxonomic monograph of Myrcia sect. Eugeniopsis (Myrciinae, Myrteae, Myrtaceae), an endemic clade of Eastern South America, Phytotaxa 703 (1), pp. 1-100 : 44-47

8. Myrcia maculata M.F.Santos (in Santos et al. 2019: 4) ( Figure 24 , 25 ).

≡ Eugeniopsis luschnathiana O. Berg (1857 –1859: 147). Type: — Brazil, Bahia, mun. Ilhéus, 1839 (fl.), Luschnath s.n. (but cited as Luschnath 7 in the protologue) (lectotype BR! [845562] designated by Santos et al. 2019; isolectotypes B†, BR! [845491], BR! [845593], BR! [845494], BR! [845524], BR! [845527], BR! [845529], BR! [845560], BR! [845595], LE! [LE00004007]).

Description:— Tree (?). Trichome reddish, simple or dibrachiate, ca. 0.1 mm. Twig when mature stramineous (when dry), cylindrical, glabrous, cortex slightly cracked with numerous pellucid dots; branching monopodial, internode 1.6– 3.4 cm, node slender; cataphylls rarely present, deciduous; buds pubescent. Leaf concolorous, chartaceous, apparently slightly corrugate, blade 5.2–9.6 × 1.9–4.0 cm, elliptic, apex acute, base cuneate, margin plane or slightly revolute, secondary veins 3–5 mm apart, held at an angle of 55° relative to the midvein, marginal vein 2.0 mm from the margin, tertiary veins inconspicuous in both surfaces, areoles ca. 2 mm, pellucid dots conspicuous in the abaxial surface, ca. 10 per mm 2; adaxial surface glabrous, secondary veins plane; abaxial surface glabrous, secondary veins raised; petiole 2–6 × 2 mm, semicylindrical, glabrous. Inflorescence 7.0–8.0 × 4.5–6.0 cm, ca. 40 flowers, axillar at the terminal or subterminal nodes of the SGU (central bud developing a vegetative branch), one inflorescence per axillary bud, inflorescence pherophyll persistent or deciduous, opposite branching, three branching per node, rachis puberulent, first internode of central rachis 2 mm wide; bracts deciduous, not seen; bracteoles deciduous, not seen. Flower bud ca. 2 × 1.2 mm, clavate (but slightly flat at the apex), corolla hidden or barely apparent before anthesis; hypanthium 1.2 mm extending above the summit of the ovary, not tearing at anthesis or with a small vertical rip (but not tearing the staminal ring), externally pubescent to puberulent, pellucid dots covering the whole surface; calyx 4–merous, lobes 0.8–1.2 × 1.0–2.0 mm, not fused, deciduous, depressed ovate to widely depressed ovate, concave, apex rounded, externally puberulent to glabrous, internally puberulent; corolla 4–merous, 1.2–1.7 × 1.2–1.7 mm, widely depressed ovate, widely ovate to very widely ovate or very widely obovate, plane, apex rounded, externally puberulent, internally puberulent to glabrous; staminal ring 0.2–0.5 mm wide, subglabrate to glabrous, stamens ca. 75, filament 2.0– 2.8 mm long, anther 0.24 × 0.24–0.32 mm, gland at the apex; ovary 1.0 × 1.0– 1.5 cm, obconic, style ca. 2.6 mm long, glabrous, stigma punctiform. Fruit and seed not seen.

Distribution and Habitat: — Myrcia maculata is known from only a few collections in the Ilhéus region of Bahia state, Brazil ( Figure 25 ). Although habitat is not explicitly recorded, it is likely to be either lowland rainforest or restinga vegetation.

Phenology: —The flowering period remains unknown due to lack of data from the type collection, and no fruiting specimen have been documented.

Conservation Status: — Myrcia maculata has only three records, one of which lack a precise location. Due to limited data available, the species is classified as Data Deficient (DD; IUCN 2022).

Taxonomy: — Myrcia maculata is a rare and poorly understood species, making its precise circumscription challenging. The type specimen displays distinctive characteristics, including stramineous branches with numerous pellucid dots and slightly corrugated leaf with occasionally revolute margins. However, it is unclear to what extent these traits may have been affected by the herborization process. Additional features include monopodial branching, elliptic leaf blades, axillar inflorescence at terminal or subterminal nodes of the SGU, and clavate flower bud with flattened apex.

Illustrations and images in previous works: —None.

Additional specimens examined: — BRAZIL. Unknown province/state, no date (fl.), unknown collector s.n. (M-0171096); no date (fl.), unknown collector s.n. (M-0171097); no date (fl.), unknown collector s.n. (M-0171098).

Bahia: unknown municipality, no date (fl.), C. F. P.Martius s.n. ( P 05131554); ibidem,1841 (fl.), B.Luschnath s.n. ( NY 615572).

Figures

FIGURE 24. Representative specimens of Myrcia sect. Eugeniopsis: Myrcia maculata (Luschnath s.n. [BR845593, copyright Meise Botanic Garden]).

FIGURE 25. Distribution of Myrcia maculata (triangles) and Myrcia tenuivenosa (circles). Solid lines represent the boundaries of South American countries and Brazilian states. The grayscale reflects elevation.