Trichanthecium hochstetteri Zuloaga, comb. nov.
Creators: name: Zuloaga, Fernando Omar
name: Aliscioni, Sandra
name: Delfini, Carolina
name: Salariato, Diego Leonel
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Poales
Poaceae
Trichanthecium
Trichanthecium hochstetteri

description: 7. Trichanthecium hochstetteri (Steud.) Zuloaga, comb. nov.
Panicum hochstetteri Steudel (1854: 90). Panicum trichanthum Richard (1851: 375), nom. illeg., non Nees, 1829. Panicum hochstetteri Steudel var. trichanthum Chiovenda (1908: 308).
Lectotype [designated as “holotype” by A. P. M. van der Zon (1992: 221)]:— ETHIOPIA (Abyssinia),” Schimper, Hrbr. Un. it. Abyss. nr. 115”, 3 October 1837, G. H. W. Schimper 115 (P [00442164!], isolectotypes BR [0000008761439!], BR [0000008367389!], ETH [000000928] image!, GOET [006772] image!, HAL [0145339] image!, HOH [008985] image!, K [000255567!], K [000255566!], K [000255568!], L [0044807] image!, L [0044808] image!, L [0044809] image!, L [0044810] image!, LG [0000090035678] image!, M [0103859] image!, MO-1660942!, MO-1093884!, P [01817882!], P [00442165!], P [00442166!], P [01817884!], P [01817885!], P [01817886!], P [00731450!], REG [000289] image!, S [05-8778] image!, S [05-8779] image!, S [05-8780] image!, TUB [006399] image!, TUB [006400] image!, US [00147885!], W [0000281!], W [18890211183!]).
Isachne refracta Hooker (1864: 227).
Lectotype [designated as “ holotype ” by A. P. M. van der Zon (1992: 221)]:— CAMEROON. “Hab. Cameroon Mountains”, 7000 ft., December 1862, G. Mann s.n. (K [000182413!], isolectotypes K [000182414!], W [0023208!]).
Panicum hochstetteri Steud. var. gracile Chiovenda (1906: 61).
Type:— SOMALIA. Villaggio di Burgi (Hamara), 11 November 1893, D. Riva 1519 (1641) (FT [000238!]).
Panicum hochstetteri Steudel var. glaberrimum Chiovenda (1908: 308).
Lectotype (here designated):— ERITREA. Sarae: Gaza-Gobo M, 1800–2000 m, 7–10 October 1902, A. Pappi 129 (FT [000237!], isolectotype US-2874903!).
Panicum mokaense Mez (1921: 189).
Lectotype (here designated):— EQUATORIAL GUINEA. Bioko (Fernando-Po), J. Mildbraed 7086 (HBG [525742!], isolectotype US [00148316!] [fragment ex B]).
Panicum cooperi Hubbard (1928: 147).
Type:— ETHIOPIA. Abyssinia: Addis Alam, 20 miles from Addis Adeba, 20 September 1926, J. O. Coopers.n. (holotype K [000255570!]).
Perennial, not tufted; culms 20–60 cm long, slender, trailing, decumbent and rooting at the lower nodes to erect; internodes cylindrical, hollow, glabrous; nodes glabrous, compressed. Sheaths striate, 2–5 cm long, sparsely hirsute to glabrous, the margins ciliate, cilia 2–3 mm long. Ligule membranous, 0.5 mm long, truncate, with long hairs beneath at the base of the blade. Blades lanceolate, 3–7.5(–11) × 0.4–1.4 cm, narrowed at the base, shortly pseudopetiolate, acute to acuminate, sparsely pilose on both surfaces to glabrous, flat, membranous, the midnerve manifest, margins scaberulous. Inflorescence a terminal, exserted, lax and open panicle 4–6(–16) × 4–16 cm; peduncle cylindrical, striate, 10–20 cm long, hirsute to glabrous; pulvini pilose to glabrous, first-order branches alternate, divergent, axis of the branches glabrous to pilose, spikelets dispersed on second-order branches, pedicels 2–8 mm long, glabrous, smooth. Spikelets oblong in outline, 2–2.5(2.6) × 1–1.1 mm, often sparsely pubescent, rarely glabrous or scaberulous, dark green, glumes and lower lemma with strong nerves; lower glume 1.5–1.7 mm long, 2/3 to 3/4 the length of the spikelet, 3(–5)- nerved, sparsely pubescent, membranous; upper glume and lower lemma subequal (5–)7-nerved, sparsely pubescent, acute, membranous; lower palea elliptic, 2.2–2.3 × 1 mm, hyaline, glabrous; lower flower staminate, anthers 3. Upper anthecium ovoid, 1.8–2 × 0.7–0.9 mm, glabrous, smooth, indurate, shiny. Caryopsis not seen.
Distribution and habitat: —Tropical Africa, from Ethiopia to Tanzania and Uganda; it grows on rocky slopes and forest shade, at 1500–3000 m elevation.
Chromosome number: —2n = 54 (Morton 1993).
Typification: —When describing Panicum hochstetteri, Steudel mentioned the specimen Schimper 115 as type, and included P. trichanthum Rich. in synonymy; the latter author cited the specimen of Schimper and also another one collected by Quarter Dillon s.n. Of these, the collection Schimper 115 from P [00442164!], was designated as “ holotype ”, and consequently a lectotype of the species. Other syntypes of this species are: Ethiopia. Ambaetcha, October 1839, R. Quarter Dillon s.n. (P [00442167!], P [00442168!], P [00442169!], W [0023203!]).
Two specimens were included in the diagnosis of P. hochstetteri var. glaberrimum, Pappi 129 and Tellini 350, FT [FT0000236!]. Of these, Pappi 129 from FT [FT 000237!] is here selected as the lectotype of the variety, since it is a complete specimen and agrees with the protologue.
The holotype specimen of P. mokaense, J. Mildbraed 7086, is lost at B, presumably destroyed during WWII Clayton & Renvoize (1982) mentioned erroneously that the holotype of this species is deposited at B. An isotype from HBG [525742!] is designated as lectotype of the species.
Note. Brown (1977) reported that this is a non-Kranz species.
Representative specimens examined: — DEMOCRATIC REPUBLIC OF CONGO. Kasindi, Lubango, January 1932, Lebrun 4828 (BR, US); Parc du Kahuzi-Biega, 20 July 1976, Dujardin 519 (BR). EQUATORIAL GUINEA. Bioco, Malabo-Moca, km 68, 24 October 1986, Carvalho 2610 (US). ETHIOPIA. 5 km W of Jinma, 15 November 1955, Stewart 173 (K, US); Amba Sea, 17 September 1863, Schimper 1087 (US); Jimma, Mooney 6033 (K); Arussi Prov.: ca. 5 km N of Asella at Kulumsa farm, Thulin 1557 (K). KENYA. Kitale, edge of riparian forest, Bogdan 4290 (K). NIGERIA. Obudu Plateau, 1 November 1964, Tuley 1028 (K, US). TANZANIA. Bez. Morogoro, Ulugura-Geb, 13 May 1933, Schlieben 3918 (K, US), 26 June 1933, 4025 (MO, US). UGANDA. Mbale District: Mount Elgon, January 1918, Dummer 3567 (K, US); West Suk, 6 miles northeast of Kapenguria, 14 November 1953, Bogdan 3855 (K, US).
description: Published as part of 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, pp. 230-264 in Phytotaxa 646 (3) on pages 245-247, DOI: 10.11646/phytotaxa.646.3.2, http://zenodo.org/record/13215433