Marasmodes defoliata S. Ortiz 2009

2. Marasmodes defoliata

S.Ortiz, Bot. J.Linn. Soc. 159:339 (2009). Type: South Africa. Western Cape, Cape Town (3318): Riverlands (Michiel Heyns Kraal), on flats, wet in winter (–BC), 25 Apr 1978, Esterhuysen 34925 (BOL!, holo.; K, iso.).

Weak, single or few-stemmed, sparsely leafy shrublets, 0.2–0.4 m tall. Leaves alternate, some rarely subopposite, restricted to upper branches or branch tips, caducous, suberect, linear to oblanceolate, 8–20 × 0.5–3.0 mm, simple or sometimes apically 2- or 3-fid, mucronulate, secondary basal lobes absent; axillary fascicles absent. Capitula solitary, terminal or on axillary shoots 5–20 mm long. Involucre broadly campanulate, 6–10 × 5–7 mm; bract margins and apices scarious, sessile glands at appendage base inconspicuous, stereome not prominent; outer bracts broadly ovate, 1.5–2.0 mm long, margin and apex not scarious; middle bracts ovate to narrowly ovate, 2–3 mm long, margin and apex at most only slightly scarious, obtuse; inner bracts oblong, 3–4 mm long, margins narrowly scarious, apex with a prominent scarious appendage, ovate to broadly ovate, reddish-pink. Florets ca. 20 to 30; limb 5-lobed from just above midpoint; lobes erect to recurved. Pappus with adaxial scales to ±half corolla tube length.

Diagnostic characters

Marasmodes defoliata

Shares the single or few-stemmed habit, sparsely leafy stems with the leaves restricted to the branch tips, and relatively large campanulate capitula (Fig. 2D & E) with M. oppositifolia but differs most prominently by the alternate primary leaves and the reddish pink scarious appendages on the innermost involucral bracts (Fig. 2E). The leaves of M. tri fi da are similarly sparse and restricted to the branch tips but M. defoliata differs in the predominantly simple primary leaves (predominantly apically trifid in M. tri fi da ), the larger broadly campanulate capitula, 6–10 × 5–7 mm (vs cylindrical-campanulate, 4–5 × 3–5 mm) and the short pappus, ±half the length of the corolla tube (vs equal to or longer than the corolla tube).

Distribution and ecology

Known only from one population at Riverlands Nature Reserve, between Atlantis and Malmesbury (Fig. 3), where it occurs on the edges of seasonally inundated places often together with Metalasia distans DC. The population consists of between 1000 and 2000 mature individuals. Due to the continued threat of habitat degradation due to dense infestations of alien invasive plants surrounding the reserve, the species is Critically Endangered, CR B1ab(iii) + 2ab(iii).

Additional specimens examined

South Africa. WESTERN CAPE: 3318 (Cape Town): Riverlands Nature Reserve, central alluvial area (– BC), 18 Mar 2009, Helme 6018 (NBG); Riverlands Nature Reserve, Middelpad, extensive seasonal wetlands in the central part of the reserve (– BC), 26 Mar 2009, Magee & Koopman 138 (NBG). Precise locality unknown: Between Malmesbury and Darling, 4 Apr 1932, Salter 2077 (BOL, K).