Sarcorhachis Trelease, Contr. U.S. Natl. Herb.

Sarcorhachis Trelease, Contr. U.S. Natl. Herb. View in CoL 26: 16. (21 May 1927).— TYPE: Sarcorhachis incurva (Sieber ex Schultes) Trel. ; Piper incurvum Sieber ex Schultes.

Vines, trailing along forest floor or climbing via rooting at nodes of monopodial axes; stems glabrous, rarely pubescent, with dark brown to black pellucid dots (ethereal oil cells) occasionally visible. Prophylls drying dark brown to reddish brown, glabrous, apex straight (acute). Leaves alternate, simple, entire; petioles glabrous, sheathing the stem, vaginate entire length with adaxial wing-like marginal tissue extending onto or stopping prior to leaf blade, the tissue eventually caducous; laminae of monopodial axes ovate to broadly ovate, symmetrical or less often slightly asymmetrical, base angle obtuse, base shape rounded, truncate, or cordate, apex angle acute, apex shape straight to acuminate; laminae of sympodial axes (if present) usually smaller and narrower, ovate to elliptic or occasionally lanceolate, base angle obtuse to acute, base shape rounded to cuneate, apex angle acute, apex shape straight to acuminate; all laminae glabrous or rarely pubescent on primary veins (above or below), or near leaf base on lower surface, darker above than below, venation palmate, basal-acrodromous to suprabasal acrodromous with 5–9(–11) primary veins often elevated below, major secondaries brochidodromous, pellucid dots round to oval, light brown to reddish brown to black, visible above and/or below upon drying, or apparently absent. Inflorescences spicate, on sympodial axes only, solitary or 2 together, appearing axillary or terminal, erect at anthesis but usually pendulous in fruit; peduncles glabrous to pubescent near rachis attachment, bracteate; rachis fleshy, pubescent; floral bracts triangular to rounded-triangular when viewed from above, ciliate to partly ciliate, rarely glabrous or with a few random hairs along margin; flowers densely grouped along the rachis, partially immersed in the fleshy axis, not forming bands around the spike; stamens 4, hypogynous, anthers 0.2–0.6 mm long with lateral dehiscence, the connective expanded at apex and appearing disk-like and glandular; ovary with 2–6 sessile stigma lobes, mostly 4, this varying among flowers within a single inflorescence. Fruits 1.15–4.0 + 0.6–1.7 mm, obovoid, glabrous, laterally compressed, embedded in rachis, drying dark brown to black with stigmatic lobes occasionally persisting.

General Distribution— The genus is found in Haiti, Lesser Antilles, Central America, and South America.

Notes— Species of Manekia (with the apparent exception of Manekia urbanii ; see notes for that species below) have an interesting growth habit relative to other Neotropical pipers. They can spend a considerable amount of time in a completely vegetative state, often trailing along the forest floor via monopodial stems. Occasionally these monopodial branches make contact with a tree trunk and they begin to climb via adventitious roots at each node. When the plant is within the canopy or sub-canopy and is exposed to increased sunlight, dangling sympodial branches are produced that bear the inflorescences. The spikes are often solitary and appear axillary in position, although this “axillary spike” is actually terminal on a highly reduced axillary branch. On occasion spikes may be paired together, both appearing to be axillary in position relative to the nearest leaf of any appreciable size. Once again, they are actually terminal on highly reduced axillary branches, with the second spike having an obvious nodose, bracteate peduncle (the leaf-like bract caducous and commonly absent on herbarium specimens).

In the descriptions provided (genus and species), leaf terminology follows Ellis et al. (2009) as much as possible; details of leaf morphology (size, shape, and specific dimensions) are based on leaves borne along the monopodial axes only. As noted in the generic description, leaves of the sympodial axes, if present, are generally smaller in size, trending toward elliptic in shape, and with fewer primary veins.