Trichanthecium inaequilatum ( Stapf & C.E.Hubb.) Zuloaga

Zuloaga, Fernando Omar, Aliscioni, Sandra, Delfini, Carolina & Salariato, Diego Leonel, 2024, Old World species of Trichanthecium (Poaceae: Panicoideae: Paniceae) including a new species from the Democratic Republic of Congo, Phytotaxa 646 (3), pp. 230-264 : 247

8. Trichanthecium inaequilatum ( Stapf & C.E.Hubb.) Zuloaga , comb. nov.

Panicum inaequilatum Stapf & Hubbard (1927: 267) .

Lectotype (here designated):— ZIMBABWE. Mutare , Umtali, 1560 m., on hillsides in shade of bush and undergrowth; 15 February 1926, Herb. Dept. Agric. S. Rhod.3375 ( K [ 000255521 !], isolectotypes K [000255522!], K [000255523!], K [000255524!], SRGH [0007632-0] image!) . Fig. 8

Perennial, not tufted, with delicate, erect, or decumbent culms from a slender rhizome; culms 10–30 cm long; internodes cylindrical, hollow, glabrous. Sheaths striate, 1.5–5 cm long., densely hispid with whitish hairs, occasionally glabrous, the margins ciliate, hairs 1–2 mm long. Ligule membranous, reduced, 0.7 mm long. Blades lanceolate, 1.5–5 × 0.3–0.6 cm, flat, subcordate, acuminate, pilose to glabrous. Inflorescence a terminal, exserted few flowered panicles, 1.5–6 × 1.5–5 cm; peduncle cylindrical, 6–12 cm long, glabrous; pulvini glabrous, main axis wavy, glabrous, first-order branches alternate, divergent, spreading axis of the branches glabrous, spikelets solitary on first-order branches, pedicels 2–10 mm long, claviform, scabrous. Spikelets long ovoid, 2–2.7 × 1 mm, sparsely to densely pilose, acuminate; lower glume 2–2.5 mm long, almost as long as the spikelet, 3-nerved, sparsely to densely pilose, membranous, acuminate; upper glume and lower lemma subequal, sparsely to densely pilose, membranous, as long as the spikelet, upper glume 7-nerved, lower lemma 5-nerved, pilose toward the apex, otherwise glabrous; lower palea elliptic, 1.8 × 0.9 mm or reduced, hyaline, glabrous; lower flower neuter or staminate, anthers 3, 1.6 mm long. Upper anthecium ovoid, 1.8–2 × 0.7–1 mm, indurate, pale, glabrous, smooth and shiny. Caryopsis not seen.

Distribution and habitat: —It grows in Eastern tropical Africa; it is found in submontane grassland, in wet places, at 1600–2400 m elevation.

Observations: — Renvoize (1989b) mentioned that the holotype of P. inaequilatum is kept at K. However, there are four type specimens at this herbarium, of which K [000255521!] is here designated as the lectotype.

The species is related to Trichanthecium eickii , from which it differs by the pilose spikelets.

Representative specimens examined: — MOZAMBIQUE. Namuli Mountain , Mozambique plateau north of two peaks, Harris 399 ( K). ZIMBABWE. Ynyanga.Inyanga National Park ; Mare Dam , 12 February 1974, Davidse et al. 6550 ( MO) ; Birkenough Bridge, Chimanimani km 86, near Skyline junction, Laegaard 16003 ( US); Melsetter District : Sawerombi Road, 16 January 1951, Cook 346 ( K, US) .

Figures

FIGURE 8. Trichanthecium inaequilatum. A. Habit. B. Ligular region. C. Detail of a branch of the inflorescence. D. Spikelet, ventral view. E. Spikelet, dorsal view. F. Lower glume. G. Lower palea. H. Upper anthecium, dorsal view. I. Stamen. J. Upper palea and gynoecium. (Cook 346 US).