Blumeodendron gesinus Ottens, 2016

4. Blumeodendron gesinus Ottens View in CoL , sp. nov. — Fig. 4 View Fig ; Map 3 View Map 3

Resembles Blumeodendron subrotundifolium but differs in the orange-brown dried leaves and the orange-brown fruits with a very distinct ridge (dark brown dried leaves and dark brown, non-ridged fruits in B. subrotundifolium ). — Type: Pereira, Wong, Sugau , Madani, Tangah , Nilus & Puff 158 (holo L; iso SAN ), Malaysia, Borneo, Sabah, Tambunan, Jalan Pegalan.

Trees, to 65 m high, bole to 25 m high, dbh to 70 cm; sometimes small buttresses present, c. 23 cm high, c. 30 cm out, c. 3.3 cm thick or fluted up to 1 m; crown spreading; flowering branches 2–3 mm diam, generally round, distance between internodes 2.5–5 cm, generally reddish brown and glabrous when dry, nodes slightly thickened. Outer bark smooth, (reddish) brown to brownish white to grey-brown to pink-brown, sometimes slightly hoop-marked, thin; inner bark chocolate brown to brownish to yellow(-green) to red(-brown) to orange-brown, c. 2.5 mm thick; sapwood white(-red) or pale yellow. Leaves always some alternate, but others subopposite to sometimes 3 in a pseudo-whorl; petiole 0.4–4.2 cm long, diam of thinnest part 1–1.5 mm, basal pulvinus 1.1–3.3 mm diam; blade elliptic, 4.6–15.3 by 2–7.4 cm, length/width ratio (1.3–)1.9–2.4(–3.3), coriaceous, symmetric, glabrous, base attenuate to cuneate, margin revolute, apex acuminate with rounded tip, extrafloral nectaries at base sometimes absent to 1 visible to 2 present, 2–11 along midrib, 2– 8 along margin, both surfaces smooth, dark green above when fresh, bright green underneath, drying greyish brown adaxially, abaxial surface orangish brown when dry; venation: marginal vein indistinct, secondary nerves (4–)6–8(–9) pairs, at c. 43.2° angle with midrib, tertiary nerves perpendicular to midrib, 1–3 mm apart, fourth order nerves often scalariform, higher order reticulate. Inflorescences axillary and terminal, thyrsoid, erect, staminate ones often 2 together, up to 11.5 cm long, flowers usually in 3-flowered cymes per node, pistillate inflorescences single, up to 3.5 cm long; bracts usually caducous, triangular, c. 0.8 by 0.2 mm, margin entire, with lepidote hairs. Staminate flowers 4.3–6.4 mm diam, yellow-green to yellow; buds 1.6–2.8 mm diam, often sticky with secretion; pedicel above abscission zone 3.1–3.3 mm long, c. 0.4 mm diam; sepals 3(–4), round, 4.5–5.3 by 2.5–3.8 mm long, completely recurved; stamens c. 27, filaments 2–4.5 mm long, anthers 0.4–0.7 mm long. Pistillate flowers 2.3–3 mm diam, pale green to yellow; sepals 5, ovate to triangular, very small, c. 0.5 by 0.5 mm, margin with few hairs; disc a c. 0.4 mm thick ring; ovary obovoid, c. 1.5–3.3 mm high by 2–3 mm wide, sutures thickened, 2(–3)-locular, style 0.3–1 mm long, stigmas 1–2.8 mm long. Fruits ellipsoid to obovoid, c. 2.5–3.8 by 3–3.5 cm, probably indehiscent because loculicidal sutures with a rounded thickened rim, green when immature, orangish brown when dry; pedicel c. 4 mm long, c. 4.5 mm diam, abscission zone in the middle, upwards strongly widening; sepal remnants sometimes persistent; disc distinct, drying brownish; wall c. 2 mm thick, surface somewhat knobbly; endocarp enclosing all seeds; stigma usually persistent. Seeds ovoid but flattened on one side, not symmetric, attached subapically, 1.9–2.5 by 1.3–2.3 by 1–1.2 cm, sarcotesta thin, veins visible.

Distribution — Borneo.

Habitat & Ecology — Lowland mixed dipterocarp forest to submontane, mossy forest, sometimes along roads in primary forest, seldom in logged over forest. Soil: yellow sandy, clay rich to ultrabasic; bedrock often sandstone. Altitude: 25–1375 m. Flowering: February–April, June, August, September; fruiting: February, May–August, October–December.

Vernacular names — Borneo: Sabah:Tampoi (Melayu); Sarawak: Bantas (Iban), Bantas ketupong, Empungan (Iban).

Notes — 1. Gesinus is the first name of the first author’s husband. The name is a personal name and not a latinisation, therefore ICN art. 60C.4 applies (http://www.iapt-taxon.org/nomen/ main.php?page=art60), the name should not be changed into gesinum.

2. This new species was generally confused with B. tokbrai , because of the long inflorescences. Very typical are the rims on the fruits and their orangish colour when dry. The same colour can be found on the lower surface of the dried leaves.

3. The variation in inflorescence lengths seems to be large, varying between short (bud) to long (flowers), but inflorescences with buds are not yet fully grown and will largely extend during maturation of the flowers.