Apoballis mutata (Scort. ex Hook.f.) S.Y.Wong & P.C.Boyce

Slender to moderately robust, erect herbs, ca 0.35–1.1 m tall. Stem epigeal, pleionanthic, ca 2–4 cm thick, often clothed with the remains of old leaf bases in the upper part, the lower part naked as these rot; internodes ca 1–4 cm diam., often with conspicuous, rather thick roots. Leaves ca 5 per module, very variable in size; petiole ca 20–45 cm long, smooth to very faintly asperous to minutely velvety-hairy, adaxially flattened to slightly channelled with the angles rounded to distally inconspicuously alate, pale green to bright dark red, sometimes somewhat glaucous (by minute hairs, not wax), sheathing in the lower ⅓–3/5 ; petiolar sheath membranous, fully attached and tapering, deliquescent/marcescent more or less immediately after emergence of leaf within; leaf blade broadly to narrowly ovate-sagittate, somewhat glossy bright mid-green to dull mid-green, usually bronze-tinged to pink when newly emerged, ca 12–40 × 6–30 cm, widest from the base to about ⅓ along midrib, the base more or less cordate with posterior lobes prominent, ca 3–12 cm long, triangular to rounded, sometimes almost overlapping across the sinus and posterior costae sometimes clearly differentiated for a few millimetres before dividing into primary venation of posterior lobes, occasionally naked in the sinus for 2–3 mm, more usually with leaf blade to the sinus and occasionally sub-peltate, the tip acute to shortly acuminate; midrib abaxially prominent; primary lateral veins 9–15 per side, sometimes branched, impressed adaxially, prominent abaxially; interprimary veins rather conspicuous and raised abaxially, impressed adaxially; secondary venation flush with leaf blade and mostly inconspicuous; tertiary venation inconspicuous. Inflorescences 2– several together; peduncle rather short, slender; spathe ca 7–15 cm long; lower spathe ca ⅓ the length of the whole, ovoid to subglobose at pistillate anthesis, green to red (correlated with petiole colour); spathe limb narrowly lanceolate, clasping the spadix, barely opening at anthesis, then closing again and temporarily persistent, eventually marcescent or breaking away after senescing, yellowish ivory to pale orange; spadix more or less cylindrical-tapering, subequalling the spathe, sessile, obliquely inserted; pistillate flower zone ca ⅓ the length of the spadix, cylindrical, ca 8–10 mm diam. at base, slightly tapering distally; interpistillar staminodes very sparsely to irregularly densely distributed amongst the ovaries, but usually concentrated at the very base of pistillate zone, stalked and clavate–headed, taller than and conspicuously larger than the pistils; sterile interstice 1–2 × 0.4–0.7 cm, composed of basal sessile interpistillar staminodes, then a concentration of smaller sessile staminodes, these becoming distant distally in small groups of commonly 2–4 surrounded by naked spadix tissue, these then usually concentrated again in an incomplete ring adjoining the staminate zone; staminate flower zone more or less cylindrical, ca 1.3–3.3 cm long, slightly thicker than top of sterile interstice, 5–8 mm diam.; stamens small, rectangular-dumbbell-shaped from above, 0.5 × 1 mm, with the thecae impressed; appendix exceeding to shorter than the staminate zone, ca 1.5–3 cm long, tapering and pointed to cylindrical and round-tipped, basally the same diameter as the staminate zone, rarely narrowly ovoid, composed of columnar flat-topped staminodes; fruiting spathe declinate, narrowly ovoid.