Malesian Euphorbiaceae Descriptions

22. CEPHALOMAPPA (Euphorbiaceae)

R. Widuri & P.C. van Welzen

Widuri, R. & P.C. van Welzen. 1998. A revision of the genus Cephalomappa (Euphorbiaceae) in Malesia. Reinwardtia 11: 153–184.

Goto on this page:

Genus description

Key to the species

Species descriptions

Cephalomappa Baill.

    Cephalomappa Baill., Adansonia 2 (1874) 131; Pax in Engl., Pflanzenr. IV.147.ii (1910) 16; Pax & K.Hoffm. in Engl. & Harms, Nat. Pflanzenfam. 2 ed., 19c (1931) 123; Airy Shaw, Kew Bull. 14 (1960) 380; Kew Bull. 16 (1963) 353; Whitmore, Tree Fl. Malaya 2 (1973) 76; Airy Shaw, Kew Bull. Add. Ser. 4 (1975) 66; Airy Shaw, Kew Bull. 36 (1981) 274; G.L.Webster, Ann. Missouri Bot. Garden 81 (1994) 79; Widuri & Welzen, Reinwardtia 11 (1998) 161; Radcl.-Sm., Gen. Euphorbiacearum (2001) 186; G.L.Webster in Kubitzki, Fam. Gen. Vasc. Pl. 11 (2014) 137. — Type: Cephalomappa beccariana Baill.

Trees, monoecious. Indumentum: next to simple hairs usually with lepidote and stellate hairs. Branches smooth to rough. Stipules small, linear, very early caducous. Leaves alternate, simple; petiole terete, basally and apically pulvinate, usually hairy; blade ovate to obovate, symmetric, coriaceous; base rounded-obtuse or acute; margin entire to crenate to dentate, flat or recurved, with glands on the lower surface, apex acuminate to cuspidate, very apex obtuse to acute, upper surface glabrous, sometimes with stellate hairs on the basal part of the midrib, lower surface hairy or glabrous; venation pinnate, raised on both sides, especially below, nerves 4–11 pairs, submarginally looped, united, veins scalariform; glands 1–4 basally beneath. Inflorescences axillary, thyrsoid, paniculate, with the stami­nate flowers in glomerules and the pistillate flowers solitary; bracts ovate, with stellate hairs, apex (obtusely) acute; bracteoles ovate or obovate; peduncles and pedicels hairy or glabrous. Flowers actinomorphic, sessile or pedicellate. Staminate flowers: calyx 3-merous, campanulate, valvate, lobes rounded or acute, thinly to densely papillate; petals and disc absent; staments 3-5; filaments basally united into a glabrous to hairy androphore; anthers subapically dorsifixed, opening latrorsly, lengthwise, smooth; pistillode small. Pistillate flowers: calyx either connate and 5-lobed or sepals free, 8, angle between lobes obtuse or acute, apex entire or bifid, acute or obtuse, with a gland; ovary echinate to densely echinate, hairy, 3- or 4-locular; ovules 1 per locule; style short to long, terete, glabrous or with stellate hairs; stigmas 3 or 4, apically entire or bifid, papillate above, smooth below. Fruit a rhegma, ellipsoid in lateral view, 3-lobed, all lobes developed, echinate to densely echinate, with stellate hairs or glabrous; wall thick, woody, smooth and glabrous inside; peduncle hairy or galbrous. Seed subglobular, smooth, glabrous, apex 2-­lobed; hilum ovate. Leaf anatomy: abaxial surface of leaf hairy or glabrous; epidermal anticlinal walls sinuous to deeply sinuous anticlinal or almost straight to sligtly wavy; stomata paracytic, elliptic.

    Distribution — Five species are recognized, all in Malesia: Malay Peninsula, Sumatra, and Borneo.

Key to the species

1. Cephalomappa beccariana Baill.

    Cephalomappa beccariana Baill., Adansonia 2 (1874) 131; Pax in Engl., Pflanzenr. IV.147.ii (1910) 17; Airy Shaw, Kew Bull. 14 (1960) 380; Kew Bull. Add. Ser. 4 (1975) 66; Widuri & Welzen, Reinwardtia 11 (1998) 163, Fig. 4–8, Map 1. — Type : Beccari PB 425 (holo FI, n.v.; iso in K), Sarawak.  

Tree. Branches rough, flowering branches c. 3.5 mm thick. Leaves: petiole 1.1–3.5 cm long, covered by dense long and short stellate hairs; blade ovate to elliptic, 4–20.2 by 2–9.3 cm, base obtuse to rounded, with a single gland at the lower surface close to the midrib, margin entire to subentire to shallowly denticulate, flat, apex acuminate to cuspidate, very apex acute, upper surface glabrous except for basal part of midrib, lower surface covered with dense short lepidote to sparse (tuffed) short to dense long and short stellate hairs, nerves 5–7 pairs. Inflorescences: peduncle 2–3.5 cm long, densely hairy; peduncle to glomerules 0.1–2.7 cm long, densely hairy, glomerules 2–5 by c. 2.6 mm; staminate bracts 0.8–1.2 by 0.2–0.4 mm; staminate bracteoles 1.2–1.4 by 0.2–0.4 mm, margin fimbriate; pistillate bracts 1–1.4 by 0.2–0.4 mm, apex obtuse, with stellate hairs. Staminate flowers 24–28 together, 1.6–3.4 by 0.1–1.2 mm; calyx tube 1.2–2.4 by 0.8–1.6 mm; lobes 0.5–0.8 b 0.3–0.5 mm, subglabrous, densely papillate; stamens 3, androphore 0.3–0.5 by 0.15–0.3 mm, subglabrous to with few stellate hairs, filaments 1.6–2.4 mm long, anther 0.6–0.8 by 0.3–0.4 mm; pistil­lode 1–2.2 mm long. Pistillate flowers: pedicels 0.2–3.1 mm long, with short lepidote hairs or long and short stellate hairs; calyx 5-lobed, with dense long and short stellate hairs; tube 0.3–1.7 by 0.9–1.8 mm; lobes 0.8–1.3 by 0.4–1.2 mm; ovary 0.9–2.3 by 0.6–2.0 mm, style 0.6–1.6 mm long; stigmas 3, 0.7–1.5 mm long, apically entire, surface papillate. Fruits 1.2–1.9 by 1.3–2.6 cm, echinate, with long and short stellate hairs, peduncle 2–4.5 cm by 1.4–2.5 mm; wall 2.7–3 mm thick. Seeds 0.7–1.3 by 0.7–1.3 cm. Leaf anatomy: leaf abaxially with dense short (75–90 µm long) lepidote hairs, or sparse to dense long (125–163 µm) and short (63–94 µm) stellate hairs; epidermis cells with slightly wavy to (deeply) sinuous anticlinal walls, 36–44 by 18–29 µm wide. Stomata 21–24 by 16–18 µm.  

    Distribution — Malesia : Borneo (Sarawak).   

Key to the varieties

var. beccariana

 

    Cephalomappa beccariana Baill. var. beccariana: Airy Shaw, Kew Bull. 14 (1960) 380; Kew Bull. Add. Ser. 4 (1975) 66; Widuri & Welzen, Reinwardtia 11 (1998) 165, Fig. 5. — Type : as the species.

 

Leaves: petioles 1.2–3.5 cm long; blade ovate, 6–12 by 4–5.8 cm, co­riaceous, base rounded, margin entire, lower surface covered with dense long and short stellate hairs. Peduncle to staminate glomerules 1.1–1.7 cm long, densely hairy; glomerules 4.5–5 by 2.6–3.1 mm. Staminate flowers 2.9–3.4 by 0.8–1.2 mm; calyx: tube 2.2–2.4 by 0.8–1.2 mm, lobes 0.7–0.8 by 0.3–0.5 mm, subglabrous; stamens: androphore 0.3–0.5 by 0.2–0.3 mm, filaments 1.8–2.4 mm long; pistillode 1.6–2 mm long. Pistil­late flowers: pedicels 1–3.1 cm long, covered with long and short stellate hairs; calyx: tube 0.3–0.5 by 1.4–1.8 mm, lobes 1.1–1.3 by 0.6–1.2 mm; ovary 1.9–2.3 by 1.6–2 mm, style 1.2–1.6 mm long, stigmas 1.3–1.5 mm long. Fruits 1.5–1.9 by 2.4–2.6 cm. Seeds 1.2–1.3 by 1.1–1.3 cm. Leaf anatomy: abaxial epidermis with dense long (125–163 µm) and short (63–94 µm) stellate hairs; epidermis cells with deeply sinuous anticlinal walls, 41–43 by 24–26 µm; stomata c. 24 by 18 µm. 

 

    

 

    Distribution — Malesia: Borneo (Sarawak).

    Habitat & Ecology — Primary lowland forest, on hill slopes with yellow sandy soil. Alt: sea level up to 275 m.

    Vernacular names — Sarawak: Mahu hutan (Malay).

    Uses — The fruit is locally eaten.

    Note — Baillon (1874) described the apex of the stigmas as bifid. We found those to be entire.

 

var. havilandii Airy Shaw

 

    Cephalomappa beccariana Baill. var havilandii Airy Shaw, Kew Bull. 14 (1960) 380; Kew Bull. 16 (1963) 353; Kew Bull. Add. Ser. 4 (1975) 66; Widuri & Welzen, Reinwardtia 11(1998) 167, Fig. 6. — Type: Haviland 2184 (K, holo, n.v.; iso BM, L, BO), Sarawak, near Kuching.

 

Leaves: petioles 1.4–2.3 cm long; blade elliptic, 4–8 by 2–4.3 cm, coriaceous, base obtuse; margin entire, lower surface with dense short lepidote hairs. Peduncle to staminate glomerules 2–5 mm long with short lepidote hairs; glomerules 2–4 by 4–6 mm. Staminate flowers 1.6–1.8 by 0.8–1 mm; calyx tube 1.2–1 by 1.2–16 mm, lobes 0.5–0.7 by 0.3–0.5 mm, subglabrous; stamens: androphore 0.3–0.5 by 0.2–0.3 mm, subglabrous, filaments 1.6–2 mm long; pistillode 1.8–2.2 mm long. Pistillate flowers: sessile or pedicelled, latter with short lepidote hairs; calyx: tube 0.3–0.5 by 1.3–1.5 mm, lobes 0.8–1.2 by 0.4–0.6 mm; ovary 1.9–2.1 by 1.6–1.8 mm, style 1.2–1.3 mm long, stigmas 0.9–1.3 mm long. Fruits 1.5–1.7 by 1.3–1.5 cm. Seeds 0.8–1 by 0.7-0.9 cm. Leaf anatomy: abaxial epidermis with dense short (75–90 µm long) lepidote hairs; epidermis cells with slightly wavy anticlinal walls, 36–42 by 18–22 µm; stomata c. 22 by 16 µm.

  

 

    Distribution — Malesia: Borneo (Sarawak).

 

var. hosei Airy Shaw

 

    Cephalomappa beccariana Baill. var. hosei Airy Shaw, Kew Bull. 14 (1960) 380; Kew Bull. Add. Ser. 4 (1975) 66; Widuri & Welzen, Reinwardtia 11 (1998) 168, Fig. 7. — Type: Hose 303 (K, holo, n.v.; iso in L), Sarawak, Baram.

 

Leaves: petioles 1.1–3.2 cm long; blade elliptic, 6–18 by 4–7.4 cm, coriaceous, base rounded, margin entire, lower surface with sparse short stellate hairs. Peduncle to staminate glomerules (0–)1–3.1 mm long, covered with dense short stellate hairs; glomerules c. 4 by 3.75 mm. Staminate flowers c. 1.9 by 0.9 mm; calyx tube c. 1.2 by 0.9 mm, lobes c. 0.7 by 0.4 mm; stamens: androphore c. 0.3 by 0.15 mm subglabrous, filaments c. 1.8 mm long; pistillode 1–2 mm long; Pistillate flowers sessile or with 1–3.1 mm long pedicels, the latter covered with dense short stellate hairs; calyx tube 1.5–1.7 by 1.4–1.6 mm, lobes 0.9–1.2 by 0.5–0.7 mm; ovary 1.8–2 by 1.7–1.9 mm, style 1.2–1.4 mm long, stigma 0.9–1.1 mm long. Fruits 1.4–1.6 by 1.9–2.3 cm. Seeds 0.7–0.9 by 0.8–0.9 cm. Leaf anatomy: abaxial epidermis with sparse short (60–94 µm long) stellate hairs. Epidermis cells with sinuous anticlinal walls, 42–44 by 25–29 µm; stomata c. 23 by 16 µm.

 

 

 

    Distribution — Malesia: Borneo (Sarawak).

 

var. tenuifolia Airy Shaw

 

    Cephalomappa beccariana Baill. var. tenuifolia Airy Shaw, Kew Bull. Add. Ser. 4(1975) 66; Widuri & Welzen, Reinwardtia 11 (1998) 169, Fig. 8 — Type: S 18041 (K, holo; iso in BM, BO), Sarawak, First Division, Lundu District, Gunong Gading.

 

Leaves: petioles 1.2–3.5 cm long; lamina elliptic, 8–20.2 by 5–9.3 cm, papery, base rounded, margin subentire to shallowly denticulate, lower surface covered with sparse stellate hairs in tufts. Penduncle to staminate glomerules 2–2.7 cm long, covered with dense short stellate hairs; glomerules c. 3 by 4 mm. Staminate flowers 1.8–2.2 by 1–1.1 mm; calyx tube 1.2–1.4 by 0.9–1.1 mm, lobes 0.6–0.8 by 0.3–0.5 mm; stamens: androphore 0.3–0.5 by 0.2–0.3 mm, subglabrous, filaments 1.8–2.2 mm long; pistillode 1.3–1.5 mm long. Pistillate flowers: pedicels 0.2–0.3 mm long, covered with dense stellate hairs; calyx tube 0.3–0.5 by 0.9–1.1 mm, lobes 0.8–1 by 0.7–0.9 mm; ovary 0.9—1.2 by 0.6–0.8 mm, style 0.6–0.8 mm long, stigma 0.7–0.9 mm long. Fruits 1.2–1.4 by 2.4–2.6 cm. Seeds 0.9–1.1 by 1–1.2 cm. Leaf anatomy: abaxial epidermis covered with sparse stellate hairs, 69–125 µm long; epidermis cells with sinuous: anticlinal walls, 41–43 by 21–24 µm; Somata c. 21 by 16 µm. 

 

 

    Distribution — Malesia: Borneo (Sarawak).

2. Cephalomappa lepidotula Airy Shaw

    Cephalomappa lepidotula Airy Shaw, Kew Bull. 14 (1960) 379; Whitmore, Tree Fl. Malaya 2 (1973) 76; Airy Shaw, Kew Bull. Add. Ser. 4 (1975) 67; Kew Bull. 36 (1981) 275; Widuri & Welzen, Reinwardtia 11 (1998) 170, Fig. 9, 10, Map 2. — Type: Beccari PS 975 (K, holo, n.v.; iso in BM, L), Sumatra, Padang Prov., Sungai Bulu.

Tree. Branches rough, flowering branches c. 3.5 mm thick. Leaves petioles 3.2–5.2 cm long, covered with dense lepidote hairs; blade elliptic, 6.5–20.2 by 3.4–5.2 cm, base obtuse, with 2 glands at the lower surface near the midrib, margin dentate, flat, apex acuminate, very apex acute, upper surface glabrous, lower surface with closely set lepidote hairs,nerves 5–9 pairs. Inflorescences: peduncle 2–3.5 cm long, densely hairy; peduncles to glomerules 0.7–1 cm long, densely hairy; glomerules 3.8–4.2 by 3.6–3.8 mm; staminate bracts c. 1.1 by 0.9 mm; staminate bracteoles 0.8–1 by 0.2–0.3 mm, margin fimbriate; pistillate bracts ovate, 0.9–1.1 by 0.8–2.2 mm; apex acute, with lepidote hairs. Staminate flowers 27–35 together, 1.6–1.8 by 0.9–1.1 mm; calyx tube 1.1–1.3 by 0.9–1.1 mm, lobes 0.4–0.6 by 0.3–0.5 mm, densely papillate; stamens 4, androphore 0.3–0.5 by 0.2–0.3 mm, glabrous, filaments 1.1–1.3 mm long; anthers 0.6–0.8 by 0.4–0.6 mm; pistillode 0.9–1.1 mm long. Pistillate flowers: pedicels 1.4–1.6 mm long, covered with dense lepidote hairs; calyx 5-lobed, with lepidote hairs, tube 0.3–0.5 by 1.4–1.6 mm; lobes 1–1.2 by 0.7–0.9 mm; ovary 0.9–1.1 by 1.1–1.4 mm; style 1.6–1.8 mm long; stigmas 3, 1.3–1.5 mm long, apically bifid, surface papillate. Fruits c. 3 by 4.2 cm, densely echinate with 2.5–3.7 mm long spines, lepidote hairs present; peduncle 1–2.9 by 1.9–2.9 mm; wall c. 2.4 mm thick, woody, inside smooth and glabrous. Seeds 1–1.2 by 0.9–1.1 cm, smooth, glabrous, apex 2-lobed. Leaf anatomy: leaf abaxially covered with lepidote hairs 87–113 µm long; epidermis cells with wavy anticlinal walls, 34–36 by 20–22 µm; stomata c. 24 by 17 µm. 

    Distribution — Malesia: Malay Peninsula, Sumatra, Borneo.

    Habitat & Ecology — Swampy forest and on hill slopes. Alt: c. 195 m.

3. Cephalomappa malloticarpa J.J.Sm

    Cephalomappa mallolicarpa J.J.Sm., Bull. Jard. Bot. Buitenz. Ser. 3, 6 (1924) 95; Merr., P1. Elmer. (1929) 160; Airy Shaw, Kew Bull. 14 (1960) 380; Whitmore, Tree Fl. Malaya 2 (1973) 76, Fig. 4; Airy Shaw, Kew Bull. Add. Ser. 4 (1975) 67; Kew Bull. 36 (1981) 275; Widuri & Welzen, Reinwardtia 11 (1998) 173, Fig. 11, 12; Map 3. — Lectotype (Widuri & Welzen, 1998): Bogor Botanical Garden VIII.F.50 (BO, hololocto), Culta Bogor Botanical Gardens. 

Tree. Branches smooth, glabrous, flowering branches c. 4.3 mm thick. Leaves: petiole 0.6–1.2 cm long, glabrous; blade obovate, 10–28.2 by 2.5–6.2 cm, base acute with 2 glands at the lower surface near the midrib. margin serrate, flat, apex cuspidate, very apex obtuse, both surfaces smooth, glabrous, nerves 8–11 pairs. Inflorescences: peduncle 2–3 cm long, glabrous; peduncle to glomerules 0.5–1.8 cm long, glabrous; glomerules 0.5–0.7 by 0.4–0.6 cm; staminate bracts 0.9–1.1 by 0.2–0.4 mm; staminate bracteoles 1.4–1.6 by 0.5–0.7 mm, margin fimbriate; pistillate bracts 0.9-1:1 by 0.3-0.5 mm, apex obtuse, subglabrous. Staminate flowers 29–36 together, 1.8–2.2 by 0.9–1.1 mm; calyx tube 1.4–1.7 by 0.9–1.1 mm; lobes 0.4–0.5 by 0.4–0.6 mm, glabrous, densely papillate; stamens 3 (or 4), androphore 0.3–0.4 by c. 0.2 mm, glabrous, filaments 1.1–1.3 mm long; pistillode 0.8–1 mm iong. Pistillate flowers: pedicels 0–2 cm long, glabrous; calyx 5-lobed, subglabrous, tube 0.3–0.5 by 1.5–1.7 mm, lobes 1–1.2 by 0.5–0.7 mm; ovary 1.5–1.7 by 2.5–2.7 mm, style c. 1.5 mm long, stigmas 3, 1.8–2 mm, apically usually bifid, upper surface papillate. Fruits 1.1–1.3 by 2.2–2.4 cm, echinate; peduncle 3–0.5 cm by 2–2.4 mm; wall 2.8–3 mm thick, woody, inside smooth and glabrous. Seeds 1.1–1.3 by 0.9–1.1 cm. Leaf anatomy: leaf abaxially glabrous; epidermis cells with sinuous anticlinal walls, 44–46 by 26–30 µm; stomata c. 26 by 16 µm.

    Distribution — Malesia: Malay Peninsula, Sumatra, Borneo (not known from Brunei and Sarawak yet).

    Habitat & Ecology — Primary forest, on hillside with a sandy-loam soil with lime. Alt: 80–600 m.

    Uses — The wood is of low quality, its durability class is V. Nevertheless, local people use it for the construction of their house.

    Note — The original syntypes, cultivated in Bogor Botanical Garden, were said to be from Mt. Salak in Java, but, this species was never found on this mountain. Up to now the species is not known from Java, therefore, Smith's (1924) suspicion of the Mt. Salak origin of the trees seems justified.

4. Cephalomappa paludicola Airy Shaw

    Cephalomappa paludicola Airy Shaw, Kew Bull. 14 (1960) 380; Kew Bull. 16 (1963) 353; Whitmore, Tree Fl. Malaya 2 (1973) 76; Airy Shaw, Kew Bull. Add. Ser. 4 (1975) 67; Widuri & Welzen, Reinwardtia 11 (1998) 176, Fig. 13, 14, Map 4. — Type: S 9713 (K, holo, n.v.; iso in L), Sarawak, Binatang Distr., Surong trib., Daro Forest Reserve. 

Tree. Branches smooth, flowering branches c. 3.2 mm thick. Leaves: petiole 0.5–0.7 cm long, glabrous; blade elliptic, 6.5–1:3 by 2–5 cm, base acute, with 4 glands at the lower surface near the midrib, margin crenate, recurved, apex acuminate-cuspidate, apex obtuse, upper and lower surface glabrous, nerves 4–6 pairs. Inflorescences: peduncle 1.6–2 cm long, glabrous; peduncle to glomerules 0.3–1.8 mm long, glabrous; glomerules 6–9 by 4–7 mm; staminate bracts 0.8–1 by 0.4–0.6 mm; staminate bracteoles 0.7–0.9 by 0.3–0.5 mm, margin entire, apex acute; pistillate bracts 1–1.2 by 0.9–1.1 mm, apex acute, subglabrous. Staminate flowers 25–33 together, 1.8–2.2 by 1.3–1.5 mm; calyx tube 1.2–1.5 by 1.3–1.5 mm, lobes 0.8–0.7 by 1–1.2 mm, thinly papillate; stamens 4, androphore 0.3–0.4 by 0.15—0.2 mm, glabrous, filaments 1.7–1.9 mm long; anthers 0.6–0.8 by 0.4–0.5 mm; pistillode 1.4–1.6 mm long. Pistillate flowers: pedicel 0–2.2 cm long, glabrous; sepals 8, free, elliptic, 1.2–1.3 by 0.3–0.5 mm, apex obtuse, entire, glabrous; ovary 1.2–1.3 by 0.9–1.1 mm, style 1.1–1.3 mm long; stigmas 4, 2–2.5 mm long. Fruits 1.4–1.6 by 2.3–2.5 cm, echinate, glabrous; peduncle 1.5–1.7 cm by 1–3 mm; wall 2.6–2.8 mm thick. Seeds 0.9–1.1 by 0.8–1 cm. Leaf anatomy: Leaf abaxially glabrous; epidermis cells with almost straight anticlinal walls, 38–42 by 1.9–2.2 µm. Stomata c. 26 by 24 µm.

    Distribution — Malesia: Borneo (Sarawak).

    Habitat & Ecology — Mainly found in freshwater peat swamp forest, also in primary forest. Alt.: sea level up to 300 m.

    Vernacular names — Sarawak: Arau, ahrau, pela.

    Uses — The wood is used as firewood.

    Note — Distinguishable from the other species by its crenate leaf margin, staminate flowers with ovate bracteoles, and the 8 free pistillate sepals with their obtuse apex.

5. Cephalomappa penangensis Ridl.

    Cephalomappa penangensis Ridl., Fl. Malay Pen. 3 (1924) 279; Airy Shaw, Kew Bull. Misc. Inf. (1923) 368; Kew Bull. 14 (1960) 379; Kew Bull. 16 (1963) 353; Whitmore, Tree Fl. Malaya 2 (1972) 76; Widuri & Welzen, Reinwardtia 11 (1998) 179, Fig. 15, 16, Map 5. — Type: Curtis 3584 (SING, iso), Malay Peninsula.

Tree. Branches rough, strong, flowering branches c. 4 mm thick. Leaves: petiole 1.8–3.2 cm long, covered with densely stellate hairs; blade elliptic, 14.5–23.5 by 7.4–10.4 cm, base obtuse, with 2 glands at the lower surface close to the midrib, margin sinuate, recurved, apex acuminate to cuspidate, very apex acute; upper surface glabrous, glossy; lower surface covered with sparse, long stellate hairs, nerves 7–9 pairs. Inflorescences: peduncle 2–2.5 cm long, hairy; peduncle to glomerules 0.4–1.2 mm long. densely hairy; glomerules 6–8 by 4–6 mm; staminate bracts 1.2–1.4 by 0.6–0.9 mm; staminate bracteoles 1.5–1.7 by 0.3–0.4 mm, margin fimbriate; pistillate bracts 1.2–1.3 by 0.6–0.8 mm, apex acute, with stellate hairs. Staminate flowers 27–34 together, 2.2–2.3 by 1.7–2.3 mm; calyx tube 1.4–1.6 by 1.7–2.3 mm, lobes 0.7–0.8 by 0.6–1.2 mm, densely papillate; stamens 4 (or 5), androphore 0.3–0.5 by 0.2–0.3 mm, subglabrous, filaments 1.9–2.1 mm long, anthers 0.7–0.9 by 0.3–0.5 mm; pistillode 0.2–0.4 mm long. Pistillate flowers: pedicels c. 0.8 cm long, with stellate hairs; calyx 5-lobed, with dense stellate hairs, tube 1.4–1.6 by 1.8–1 mm; lobes 0.3–0.4 by 0.3–0.5 mm; ovary c. 2.3 by 2.5 mm, style 1.6–1.8 mm long, stigmas 3, 1–1.2 mm long, apically entire, upper surface papillate. Fruits 1.4–1.8 by 2.2–2.4 cm, echinate, suglabrous; peduncle 1–3 cm by 1.3–2 mm; wall 2.7–3.1 mm thick. Seeds 1–1.2 by 1.1–1.3 cm. Leaf anatomy: leaf abaxially covered with long stellate hairs, 125–225 µm long; epidermis cells with deeply sinuous anticlinal walls, 42–44 by 26–28 µm. Stomata c. 23 by 17 µm.

    Distribution — Malesia: Malay Peninsula.

    Habitat & Ecology — Lowland forest. Alt.: c. 90 m.

    Note — C. penangensis resembles C. beccariana var. tenuifolia, but the latter has thin leaves with a flat denticulate margin. C. penangensis, unlike the other species. has much stouter petioles and stiff recurved leaves with a sinuate margin.