Ancistrothyrsus scopae Feuillet, 2020

Feuillet, Christian, 2020, Ancistrothyrsus scopae (Passifloraceae), a new species from Amazonian Brazil and Guyana, with keys to the genus and species, Phytotaxa 438 (3), pp. 207-212 : 209

Ancistrothyrsus scopae Feuillet , sp. nov.

Type. — GUYANA. Potaro-Siparuni Region: Mt. Ayanganna , east face, 5°20’04”N, 59°55’30”W, 712 m, 20 June 2001, fruit, H. D. Clarke, R. Williams, C. Perry, E. Tripp,& J. Kelly 9663 (holotype US-1692615! [scan 01886149]; isotypes MO!, OSC! [fruit only], P!) Fig. 1 (top left)

Diagnosis.— Species nova in Ancistrothyrsum pertinet, autem ab aliis speciebus ex longioribus trichomatibus multi-verticillatis ramosis differt.

Description.—Woody climbers. Stems terete, hairy; young stems tomentose with hyaline trichomes ca. 0.3 mm long and hirsute and with branched trichomes looking like bottlebrushes, up to 5 mm long, main stem of the trichomes straw-colored when dry with an occasional black one, short branches in tiers, spreading, hyaline; older stems tomentose with a few bottlebrush trichomes. Stipules reduced to a rim with long hyaline tomentose/ciliate trichomes at margin, hidden among the hirsute trichomes on the young stems. Tendrils with the same indumentum as the leaves. Leaves alternate: petiole canaliculate, 1–1.7 cm long, indumentum similar to the stem; lamina oblanceolate, 6–23 × 3.5–12 cm, base acute to cuneate, apex obtuse, margin entire or with minute mucronate teeth, on short branches, leaves adaxially scarcely and shortly tomentose, peltate scales with small erect trichomes at the margin, and denser indumentum on the veins, loosely arachneous on large leaves of the main stem, abaxially densely tomentose, 7–10 main veins on each side of the midrib. Inflorescences axillary on short branches with leaves 3.5–9 cm long, compound-cymose, tomentose, terminal flower of the triads developing as a hook; peduncle 2–2.5 cm long; bracts 1–1.5 mm long, scale-like; bracteoles shorter than the bracts; pedicels 4–5 mm long; hooks swollen, indurate, semicircular ca. 1cm diam., sessile or nearly so. Flowers not seen; according to the labels, white with “stamens yellow”. Fruits yellow-orange, stipitate, ellipsoidal, 8–10 × 6–7 cm, dehiscent 4-valved, with two kinds of trichomes, stiff appressed and patelliform, pericarp rigid, 7–10 mm thick; Seeds 1.2 × 0.7 × 0.4 cm, 8–10 ovules per placenta, not all ovules developed into seeds.

Distribution. Guyana (Mt Ayanganna), Brazil (Amazonas, Manaus), 80–715 m, in terra firme forest. The label of the type collection says: dense forest on brown sandy clay and laterite, with Dicymbe , Pentaclethra , and Micrandra .

Phenology. Flowering (January) and fruiting (January, June, December).

Etymology. The Latin noun in apposition scopae is a nominative plural meaning brooms or brushes. It is a reference to the branched trichomes looking like bottlebrushes typical of that species.

Additional specimens studied: BRAZIL. Amazonas : Igarapé do Bindá , 25 May 1961, fr., W. A. Rodrigues & J. Chagas 2631 = INPA 9175 ( INPA!), 11 January 1962, fl., W. A. Rodrigues & J. Chagas 4074 = INPA 10639 ( INPA!, NY! [scan NY01291499 !]) ; Manaus , Estrada do Aleixo, 25 January 1932, fl. & fr., A. Ducke JBRJ-24384 (JBRJ- 2 [scans RB00271367 ! & RB00776286 !], K [scan K001185245 !], P-2! [scans P06719670 ! & P06719672 !], US!) ; estrada Manaus-Itacoariara , km 47, 28 December 1960, fr., W. A. Rodrigues & L. Coêlho 2024 = INPA 8398 ( INPA!) .

Figures

FIGURE 1. Ancistrothyrsus scopae sp. nov.: top left, A. Ducke JBRJ-24384 (US!) – top right, young stem with bottlebrush trichomes, A. Ducke JBRJ-24384 (US!) – bottom left, bottlebrush trichomes, Rodrigues & Chagas 2631 (INPA!) – bottom middle, three inflorescences in bud with terminal tendrils showing swollen apex varying from hooked to shortly coiled, A. Ducke JBRJ-24384 (US!) – bottom right, open capsule and seeds, H.D. Clarke, R. Williams, C. Perry, E. Tripp, & J. Kelly 9663 (isotypes: OSC!). All photos C. Feuillet.