Diospyros taikintana G.E. Schatz & Lowry, 2021

Schatz, George E., Lowry Ii, Porter P., Rakouth, Hasina N. & Randrianaivo, Richard, 2021, Taxonomic studies of Diospyros (Ebenaceae) from the Malagasy region. VI. New species of large trees from Madagascar, Candollea 76 (2), pp. 201-236 : 234-236

Diospyros taikintana G.E. Schatz & Lowry , sp. nov. ( Fig. 18 ).

Holotypus: MADAGASCAR. Reg. Sofia [Prov. Mahajanga]: Ambohimirahavavy , 19.I– 12.II.1951, ♀ fl., Humbert & Capuron 24919 (MO-6956011!; iso-: G [ G00341739 ]!, K!, P [ P00580401 , P03829461 ]!, TAN!, US!, W!) .

Diospyros taikintana G.E. Schatz & Lowry resembles other members of the Squamosa group in having leaves with the midvein impressed adaxially and female flowers enclosed within multiple distichous, overlapping, scale-like bracts in bud, but is distinguished by its small leaves (3–5.5 × 0.8–2.3 cm) with dense indumentum on the abaxial surface, often 3-merous female flowers, and squamose floral bracts that form a nearly spherical cluster around each bud.

Tree 18 –25 m tall, 25 – 40 cm DBH. Bark thin (5 mm), nearly entirely black. Young stems terete, dark brown to blackish, with numerous small lenticels, moderately densely covered with short, erect, straight to curly trichomes c. 1 mm long and/ or long, fauve, appressed trichomes c. 1 mm long, glabrescent. Leaves distichous, lamina 3–5.5 × 0.8–2.3 cm, narrowly ovate to elliptic or occasionally oblong, coriaceous, glossy above, initially with appressed trichomes c. 0.1 mm long, glabrescent, matte below, initially densely covered with white, silky, appressed trichomes to c. 1 mm long and rusty, appressed trichomes c. 0.1 mm long below, glabrescent, base obtuse to rounded, margin flat, apex acute to acuminate, midvein raised to slightly impressed above, glabrous or densely covered with white, curly, semi-appressed trichomes, raised below, venation weakly brochidodromous, with 6–9 secondary veins per side, indistinct to faintly visible and slightly raised above, slightly raised below; petiole 1–4 mm long, 0.7–1 mm in diam., terete to slightly flat-topped or canaliculate, densely covered with curly, semi-appressed, white to light golden trichomes 0.7 mm long and appressed, rusty trichomes 0.1 mm long, glabrescent. Male flowers not seen. Female flowers solitary, in the axils of leaves, 3(–4)-merous, pedicel 1–2 mm long, 0.5 mm in diam., bearing 7–9 distichous, overlapping, cucullate, scale-like bracts enclosing the flower in bud, 1.5–5 × 1.5–6 mm, broadly elliptic to circular, cucullate, becoming progressively larger from the base to apex of the pedicel, densely covered outside with white and fauve, appressed trichomes, glabrous inside, the margins densely ciliate; sepals fused into a cupular calyx, 3–4 × 4.5 mm, apex truncate, without any evident lobes or sometimes with three or four groups of trichomes slightly exserted above the rim, densely covered outside with appressed, fauve trichomes, glabrous inside; fused corolla with short (1.5 mm) urceolate tube and 3–4 spreading lobes, cream white, lobes 3 × 3 mm, apex rounded, densely covered outside with fauve, appressed trichomes, glabrous inside; staminodia 9, inserted on the corolla tube just below the lobes; ovary ovoid, 2–3 mm long, style 1–2 mm long, with 3–5 flat-topped stigmatic branches. Fruits axillary, solitary, pedicel in fruit 1 –1.5 mm, 2 mm in diam., glabrous, bearing numerous bract scars; fruiting calyx broadly cupuliform, 4–5 × 9–10 mm, 3–4-lobed, the lobes broadly triangular, 2 × 5 mm, margin revolute, the apex strongly reflexed, densely covered outside with a mixture of semi-appressed, blackish and dark brown trichomes 1–1.5 mm long, glabrous inside except with shorter trichomes apically along the rim and exposed surface of lobes, pedicel scar 2 mm in diam.; fruit spherical to slightly obloid, the apex slightly depressed, 7.5–8.5 × 7.5–9 mm, glabrous, light brown, shiny, crowned by the persistent style/stigma, 1–1.3 mm long. Seeds 3–4, flattened ellipsoid, 6–7 × 4–5 mm, glabrous, black, shiny.

Etymology. – The species epithet is the Malagasy word for pill bugs, members of the isopod family Armadillidiidae , which, when rolled into a ball to assume a defensive posture, strongly resemble the squamose bracts that subtend the flower buds of Diospyros taikintana .

Distribution and ecology. – Diospyros taikintana is known from a single locality in the Ambohimirahavavy massif in the northern part of the island ( MADAGASCAR CATALOGUE, 2021), where it was collected in high-elevation subhumid to montane forest.

Phenology. – Flowering and fruiting material was collected in February.

Conservation status. – Diospyros taikintana has an extremely restricted geographic range in the form of an Area of Occupancy of 4 km ². It is present only in the protected area of COMATSA Nord. Given the isolated and remote nature of its distribution, there are no known external threats. Therefore, D. taikintana can be assessed as “Least Concern” [LC], with the caveat that such a status is contingent upon the effective management of the COMATSA Nord protected area.

[A, D: Service Forestier 983, P; B–C, E–F: Service Forestier 988, P] [Drawing:Alain Jouy]

Notes. – Diospyros taikintana is possibly a member of the Squamosa group, which comprises nine species characterized by having leaves with the midvein impressed adaxially, and female buds and flowers enclosed within multiple distichous, overlapping, scale-like bracts (SCHATZ & LOWRY, 2020). Within the Squamosa group, D. taikintana would be distinguished by its leaves with small lamina (3–5.5 × 0.8–2.3 cm) bearing dense indumentum on the abaxial surface, often 3-merous female flowers, and floral bracts that form a nearly spherical cluster around each bud.

We strongly suspect that the material of this species represents just two collections, one in flower comprising Humbert & Capuron 24919 and Service Forestier 983, and the other in fruit, represented by Humbert & Capuron 24927 and Service Forestier 988. Indeed, when Capuron was in the field with Humbert (and others, e.g. Leandri), he routinely reserved material of woody collections for the Service Forestier series, resulting in a single gathering entered into both Humbert’s and the Service Forestier number series.

Additional specimens examined. – MADAGASCAR. Reg. Sofia [Prov. Mahajanga]: Ambohimirahavavy , 19. I –12.II.1951, fr., Humbert & Capuron 24927 ( FHO, MO, P, TAN, WAG) ; ibid. loco, 5.II.1951, ♀ fl., Service Forestier 983 ( G, MO, P [2 sheets], TEF) ; ibid. loco, 6.II.1951, fr., Service Forestier 988 ( G, K, NY, P [2 sheets], TEF, US, W) .

Figures

Fig. 18. – Diospyros taikintana G.E. Schatz & Lowry. A. Branch with flower buds; B. Branch with fruits; C. Detail of leaf venation (abaxial surface); D. Detail of flower bud with subtending bracts; E. Fruit (seen from side); F. Fruit (seen from above).