Encephalartos ferox subsp. ferox

Rousseau, Philip, Vorster, Pieter J., Afonso, Abilio V. & Van Wyk, Abraham E., 2015, Taxonomic notes on Encephalartos ferox (Cycadales: Zamiaceae), with the description of a new subspecies from Mozambique, Phytotaxa 204 (2), pp. 99-115 : 105-107

Encephalartos ferox subsp. ferox ( Figs 3 , 5A, B & 7C, D )

Literature citation (descriptions):— Prain (1917); Hutchinson & Rattray (1933); Schuster (1932); Ogilvie (1939); Lewis

(1960); Dyer (1965a); Dyer & Verdoorn (1966); Giddy (1980); Osborne (1987); Goode (1989); Norstog & Nicholls (1997); Heibloem (1999); Goode (2001); Grobbelaar (2002); Jones (2002); Whitelock (2002); Cooper & Goode (2004).

Iconography citation:— Ogilvie (1939: 656): plate IV; Dyer (1965a: 500): figures 85–87; Lewis (1960: 80): table 1B; Dyer & Verdoorn (1966: 27): figure 7; Osborne (1987: 14): front cover, figures 2–9; Giddy (1980: 111): plate 26.1–26.5; Goode (1989: 141): pp. 141– 143; Phelan et al. (1993: 11): figure 3; Nel (1993: 25): p. 25; Rautenbach (1995: 37): figure 1; Norstog & Nicholls (1997: 130): colour figure 1, 35, 59; Heibloem (1999: 56): pp. 56–57; Claasen (1999: 18): front cover, colour figure 7; Henning (2000: 17): colour figure 6; Grobbelaar (2001: 13): colour figure 9; De Haas (2001: 18): colour figure 23; Goode (2001: 294): pp. 294–297; Grobbelaar (2002: 180): figures 6.13.1–6.13.4; Jones (2002: 264): p. 264; Whitelock (2002: 48): plate 262–265; Nel (2003: 25): figure 1, colour figures 26–31; Cooper & Goode (2004: 73): plate 26; Surju (2005: 23): pp. 23–24; Steenkamp (2008: 38): p. 38; Hurter (2009: 35): figure 7; Retief (2009: 35): figure 8; Du Toit (2010: 40): p. 40; Tang (2011a: 21): figure 5; Tang (2011b: 26): figures 2–4, 7–12; Rousseau & Mann (2012: 21): figures 1–7, 9–15; Rousseau (2013: 28): figure 3.

Stems subterranean, rarely emergent 150–1000 [300] mm long. Leaves (1060–)1280–2323(–2680) [1818] mm long; unarmed section of petiole (0–15–)30–65(75–160) [64] mm long with 2–4(–6) spines present. Median leaflets length × width × spacing: (125–)140–193 [153] × 33–52(59–65) [46] ×32–49(55–84) [47] mm. Leaflet pairs (25–)30–37(– 45) [34], veins (27–)35–43(–53) [40]. Microstrobili predominantly orange to red very rarely yellow, length 320– 440(–960) [427] mm, circumference 260–355 [304] mm; peduncle length (160–)200–370(–440) [236] mm; median microsporophyll height (27–)32–40(–44) [35] mm. Megastrobili predominantly red, very rarely orange to yellow, length (300–)440–510(–575) [418] mm, circumference (490–)634–705(–740) [626] mm; peduncle length (65–)85– 117(–140) [91] mm, circumference (141–)157–219 [177] mm; Median sporophyll height 62–87 [78]mm, sporophylls concolourous externally and internally. Seedling leaflet width 10–18 [15] mm.

Habitat:— Encephalartos ferox subsp. ferox is near-endemic to the Maputaland Centre of Endemism ( Van Wyk & Smith 2001). It is found in Miombo Woodlands on Lake Basin and Sul do Save Sands ( Fig. 3A ), Brachystegia spiciformis Bentham (1866: 312) (Vegetation type 20, Wild & Barbosa 1968) & Littoral dunes, Mimusops caffra Meyer ex de Candolle (1844: 203) (Vegetation type 14b, Wild & Barbosa 1968) and CB 1: Maputaland Coastal Belt ( Mucina & Rutherford 2006). Rainfall 1000–1250 mm per annum, elevation 20–100 m ( Donaldson 2010).

Distribution:— SOUTH AFRICA: KwaZulu-Natal; MOZAMBIQUE: Maputo, Gaza, Inhambane. In South Africa it is only found in northeastern KwaZulu-Natal, the main distribution is in the province of Maputo, Gaza and Inhambane in Mozambique. It has not been located north of the Save River despite anecdotal claims by Capela (2006).

Taxonomic notes:— See Table 1.

Phenology:— Strobili found dehiscent/receptive (day/month): 23/03, 30/04 ; Inhambane, 29/04; Mapinhane, 29/04; Pomene , 30/4 ; Paindane , 01/05 ; Zavora , 02/05 ; Chidenguele ; seed shedding around September.

Fauna:— Porthetes Schoenherr (1838: 1041) sp. nov. 7 ( Oberprieler 1995, Downie et al. 2008) is known as probable pollinators, while a novel species of Erotylidae has been found here at all localities visited. The following Geomitridae ( Lepidoptera, Staude 2001 , Staude & Sihvonen 2014) are also known to feed on the subspecies: Paraptychodes Warren (1894: 379) sp. , Diptychis meraca Prout (1928: 19) , Zerenopsis moi Staude & Sihvonen (2014: 27), and Z. lepida Walker (1854: 571) . Seed sarcotesta is routinely removed (consumed) though the agent(s) responsible are unknown. A seed dispersal agent seems absent as dispersal is very poor with many crowns littered with seed and even germinating seedlings.

Etymology: —Specific epithet from the Latin ferox = fierce, alluding to the large almost lobe-like leaflet teeth which are hard, stiff and sharp.

Representative specimens:— MOZAMBIQUE. Tofo: Rousseau & Mann 26–28 (PRU), Mapinhane: Rousseau 1183B, Rousseau 1184 (PRU), Quewene/Belane: Rousseau 1257–1260 (PRU), Pomene: Rousseau 1185–1187 (PRU), Paindane: Rousseau 1188–1189 (PRU), Zavora: Rousseau 1190–1191 (PRU), Chidenguele: Rousseau 1192–1193 (PRU), ex Xia Xia: Rousseau 1046 (PRU), Xai Xai: Jan de Koning 1.P1 (LMU), Chihanga: Maneul Fildalgo de Carvalho 1.281 (LMU), Pomene: Jan de Koning & Daniel Zunguze 8971 (LMU), Inharrime: F. de Lemos & A. Balsinhas 160 (LMA), Pomene: Jan de Koning & F. Hiemstra 8971 (LMA), Vila de Joã Belo Praia de Sepuilveda: L.A. Grandvaux Barbosa & F. de Lemos 8328 (LMA), Zavala: IIAM 9 (LMA), Chongoene: Ajuian Maan & A. Baldjuihas 1107A (LMA), Praia de Sepuilveda: J.G. Fedro 3463 (LMA), Chongoene: Pedro & Pedrogão 1647 (LMA), Quissico: Pedro & Pedrogão 1872 (LMA), Vila de Joã Belo: A.R. Torre 3879 (LMA). SOUTH AFRICA. KwaZulu-Natal: Rousseau 651 (JRAU), Rousseau 715 (JRAU), Rousseau 771 (JRAU), Rousseau 841 (Manie v/d Schijff #4380, JRAU), Rousseau 844, Rousseau 993 (Manie v/d Schijff #1452, JRAU), Rousseau 1013 (National Botanical Garden #3130610, JRAU), Molyneux G s.n. Barcode #000076187 – 000076188 (K).

Strobilus volatile chemistry:— Of the 19 Encephalartos taxa analysed by Suinyuy et al. (2013), E. ferox subsp. ferox was unique with a volatile composition dominated by alkanes (99%).

Hybrids:— No natural hybrids are known as no other species of Encephalartos occur within the distribution range of E. ferox . Artificial hybridisation between E. ferox and other members of the genus — which generally hybridise easily with each other — has been mostly unsuccessful (Vorster, unpublished data). Known artificial hybrids (Vorster, unpublished data) have produced very low yields but include, E. ferox × E. woodii Sander (1908: 257) , E. ferox × E. trispinosus Dyer (1965b: 112) , and E. ferox × E. caffer Thunberg (1775: 284) (see: Holzman 2005).

Conservation status: —Threats include removal for local and foreign horticulture, high burning frequency of grassland habitats kills seedlings and habitat is destroyed for coastal development and agriculture. Cousins et al. (2011) found ca. 10% of the Encephalartos material traded at the Warwick traditional medicinal market (Durban) to be cf. E. ferox where whole individuals are removed.

IUCN Red List status:—In 1997: Rare ( Walter & Gillett 1998), in 2003: Least Concern ( IUCN 2003), in 2012: Near Threatened ( Donaldson 2010). The suggested Red List categorisation is still at Near Threatened as the increased stability (at least in the southern parts) of Mozambique has seen a noticeable rise in the tourism in E. ferox habitats, which simultaneously destroys habitats and subsequently sources plants from other areas for cultivation.

Figures

FIGURE 3. Encephalartos ferox subsp. ferox. A. Plants in habitat at its northernmost distribution; associated with forest on coastal dunes, often in the shade of taller trees and shrubs. B. Mature microstrobilus C. Receptive megastrobili. D. Megastrobilus; rare yellow form.Scale bars = 50 mm. Vouchers: B = Rousseau 1046, C = Rousseau 1185. Photographs: P. Rousseau.

FIGURE 5. Encephalartos ferox: morphology of median leaflets. A. Subsp. ferox; from southernmost populations (= E. kosiensis). B. Subsp. ferox; from northernmost population. C. Subsp. emersus. Scale bar = 40 mm. Photographs: P. Rousseau (A), P.J. Vorster (B & C).

FIGURE 7. Encephalartos ferox: megasporophyll detail. A. Subsp. emersus; transverse section of megastrobilus with green internal tissue. B. Subsp. emersus; median megasporophyll outer surface detail. C. Subsp. ferox; transverse section of megastrobilus with red internal tissue. D. Subsp. ferox; median megasporophyll outer surface detail. Scale bars: A & C = 30 mm, B = 20 mm. Vouchers: A = Rousseau & Man 39, B = Rousseau 1252, C = Rousseau 1183B. Photographs: P. Rousseau.