Curarea barnebyana R.Ortiz, 2018

Ortiz, Rosa del C., 2018, A taxonomic revision of Curarea Barneby & Krukoff (Menispermaceae), PhytoKeys 100, pp. 9-89 : 23

1. Curarea barnebyana R.Ortiz sp. nov. Figs 11 , 12

Diagnosis.

The species is distinguished by its coriaceous leaves that are narrowly ovate or elliptic, with dense brown villous indumentum, primary branches of the staminate inflorescence contracted/condensed and drupelets broadly obovoid or ellipsoid.

Type.

Ecuador. Pastaza: Pastaza Canton , pozo petrolero “Moretecocha” de ARCO 75 km al. este de Puyo, bosque húmedo tropical, 01°34'S; 77°25'W, 580 m, 4-21 Oct 1990, (♂ fl), Gudiño, Quelal & Caiga 952 (holotype: MO!; isotypes: QCNE!, NY!, US!).

Note.

Ortiz-Gentry (2000; unpublished MS thesis) provisionally used the epithet phaeofusca for this taxon.

Description.

Large canopy lianas about 20-30 m tall; older stem 6-20 cm wide, strongly flattened, with shallow lengthwise fissures; bark dark brown; branchlets densely coarsely dark brown villous tomentose. Leaves: blades 9-15 × 6-11 cm, ovate to elliptic, subcoriaceous to coriaceous when mature or when exposed to direct sunlight in the canopy; surfaces discolorous, lustrous and glabrous adaxially, coarsely dark brown or cream villous abaxially, trichomes concealing the epidermis at all stages, base obtuse to rounded, apex acuminate or retuse, cuspidate when juvenile, 5(7) palmati- or plinerved, innermost pair of main veins acrodromous perfect on mature leaves, acrodromous imperfect on juvenile ones, midrib and secondary veins slightly impressed adaxially, conspicuously raised abaxially, secondary veins 1-2 pairs, arising above the middle of the blade, veinlets immersed on the adaxial surface, raised abaxially; petioles 2.5-8.5(-15) cm long, terete, densely dark brown villous, apical pulvinus terete, rugulose. Staminate inflorescences solitary, axillary or slightly supra-axillary, thyrsi (Fig. 11A-B ), densely dark brown villous; axes 7.4-9 cm long; primary branches, 1.2-1.9 cm long, with compact and reduced (0-1) branching orders; bracts 0.9-1.1 mm long, narrowly ovate, concave, fleshy, glabrous adaxially, dense dark brown villous abaxially. Pistillate inflorescences, solitary or fascicled, axillary, few-flowered thyrsi, the primary branches reduced to single flowers (Fig. 12A ), indumentum as on staminate inflorescences; axes 4.8-5.3 cm long, terete or angular; bracts 0.7-1.1 mm long, ovate, concave, fleshy, glabrous adaxially, brown villous abaxially. Staminate flowers 1.4-1.7 mm long, cream to brownish; pedicels ca. 0.9-1.9 mm long, terete, indumentum as on the axis; bracteoles 1-2, 0.3 × 0.1-0.2 mm, ovate to oblong, fleshy, glabrous adaxially, brown tomentose abaxially; sepals 6, glabrous adaxially, brown tomentose abaxially; outer sepals 0.6-0.7 × 0.3-0.5 mm, ovate or oblong, base truncate, apex acute; inner sepals 1.3-1.5 × 1-1.3 mm, obovate or obovate-rhombic, base obtuse, apex obtuse or rounded, tip of inner sepals erect but not reflexed past anthesis; petals 6, 0.6-0.7 × 0.3-0.5 mm, inner ones a little narrower, obovate-rhombic, weakly concave, glabrous adaxially and abaxially, base obtuse to cuneate-truncate (shortly clawed), lateral margins inflexed, partially clasping the filaments, apex obtuse, acute or weakly retuse; stamens 6; filaments 0.4-0.5 mm long, clavate, moderately thick, free or shortly connivent, glabrous; anthers 0.2-0.3 mm long, erect, connective forming a conical-shaped protrusion adaxially, (Fig. 11G ), not protruding beyond thecae apically. Pistillate flowers 1.6 mm long, brownish; pedicels 3.2-3.6 mm long, terete; bracteoles 2, 0.4-0.5 × 0.3 mm, ovate, fleshy, glabrous adaxially, brown tomentose abaxially; sepals 6-9, in 2-3 whorls, weakly concave, slightly fleshy to fleshy, glabrous adaxially, brown tomentose abaxially; outer sepals, 0.6-0.9 × 0.3-0.6 mm, ovate or oblong, base truncate, apex obtuse; middle sepals ca. 0.9 × 0.8 mm, obovate, base and apex obtuse; inner sepals 1.1-1.6 × 1-1.5 mm, weakly obovate or elliptic, base and apex obtuse, tips erect to reflexed past anthesis; petals 3, 0.8-1.3 × 0.6-1.4 mm, spatulate, weakly concave, glabrous adaxially, glabrous or sparsely tomentose abaxially, base clawed, apex retuse; carpels 3, 0.4-0.9 × 0.3-0.7 mm, dark brown villous tomentose, indumentum appressed-ascending; style 0.4-0.5 mm long. Infructescences axes 2-6.7 × 0.3-0.5 cm, indumentum as on pistillate inflorescences; fruiting pedicel 0.3-0.6 cm, clavate; carpophores triangular or subglobose, ca. 3.6 mm long, convex at apex, dark brown villous. Drupelets 2.9-4.5 × 2.3 3.1 cm, yellow or orange when ripe, narrowly obovoid to ellipsoid (Fig. 12F ), weakly laterally flattened, at times gradually attenuate toward the base; base obtuse, strongly eccentrically attached; stylar scar not apparent; exocarp 4-6 mm thick, surface rugose, dark brown villous tomentose, granular when dried; mesocarp thin, mucilaginous; endocarp 2.5-3.5 × 1.5-1.9 cm, chartaceous, surface smooth. Seeds with embryo 5.8-6.9 cm long, cotyledons slightly unequal.

Distribution and ecology.

Andean foothills of eastern Ecuador and eastern Peru (Fig. 9 ), at elevations of 200-450 m in tropical wet forest. Staminate flowering specimens were collected in January, June and October; fruiting and old pistillate flowering specimens were collected in January and June.

Common names and uses. Ecuador.

“jondomebo” (Huaorani) ( Gudiño et al. 952, ♂ fl).

Eponymy.

The specific epithet honours the late Dr. Rupert C. Barneby whose work has laid the foundations for all subsequent taxonomic studies of neotropical Menispermaceae .

Conservation status.

The calculated Extent of Occurrence (EOO) based on ten collections representing six localities of C. barnebyana resulted in 72,674 km2, whereas the Area of Occupancy (AOO) was estimated as 24 km2. Of the six sub populations representing four locations, two of the latter are found nearby private or national protected areas in eastern Ecuador and is very likely that more individuals will be found within these areas. Of the two other locations found across the border, in Peru, one of them is in a rather continuous tract of forests, whereas the other is found in a nearby area where there is increasing deforestation, which may result not only in a decline in habitat quality, but also likely reduction of the geographic range of the species in the future. Based on these considerations, C. barnebyana is assigned a preliminary status of "Vulnerable " [VU, A3c + B1b(i,ii,iii,iv) + B2b(i,ii,iii,iv)].

Discussion.

C. barnebyana is recognised by its large obovoid or ellipsoid and weakly laterally flattened drupelets covered with a dark brown villous tomentose indumentum and borne on claviform fruiting pedicels. Similar indumentum is found in C. tecunarum , but the primary branches of the staminate inflorescences of the latter are laxly branched, while the primary branches of the inflorescences of C. barnebyana are condensed similar to those of C. crassa and C. candicans (see discussion under C. crassa ). Shared anatomical features amongst these species, which make up group 1, are summarised in Table 5 . In the fruiting condition, C. barnebyana loosely resembles C. crassa , but it is readily distinguished by its relatively long (ca. 8 cm in length) infructescence axis, clavate fruiting pedicels and narrowly obovoid to ellipsoid drupelets that are weakly laterally flattened and have a dark brown indumentum. Curarea crassa , on the other hand, has a short (ca. 0.5-2 mm long) infructescence axis, terete fruiting peduncles and broadly obovoid drupelets with a dense, golden villous indumentum.

Paratypes.

ECUADOR. Napo: Parque Nacional Yasuní, Pozo Petrolero Daimi 2, 00°55'S; 076°11'W, 200 m, 26 May-8 Jun 1988, (fl bud), Cerón & Hurtado 4094 (MO!, QCNE!); Canton Tena Estación Biológica Jatun Sacha, 8 km al. este de Misahuallí, bosque muy húmedo tropical, 01°04'S; 077°36'W, 400 m, 23-31 Jan 1989, (imm fr), Cerón 6008 (G!, MO!, NY!, QCNE!); Reserva Etnica Huaorani, Carretera y oleoducto de Maxus en construcción, km 86-89, 00°51'S; 76°15'W, 260 m, 25-30 Mar 1994, (mat fr), Dik 1213 (MO!, QCNE n.v.); Canton Tena Estación Biológica Jatun Sacha, 450 m, 7 Jan 1989, (imm fr), Neill 8705 (G!, NY!, QCNE!); ibid., (♀ fl & imm fr), Neill 8712 (G! [2], MO!); Estación Biológica Jatún Sacha, 28 Jun 1996, (♀ fl & imm fr), Ortiz & Vargas 194 (MO! [2]); ibid., 29 Jun 1996, (♀ fl & imm fr), Ortiz & Vargas 195 (MO!); ibid., 3 Jul 1996, (♀ fl & imm fr), Ortiz & Vargas 200 (MO!).

PERU. Loreto: Campamento Forestal, 16 km from the Ecuador border near Río Conventes, overgrown road cut margins, [02°25'S; 076°10'W], 12 Apr 1979, (old fr), Aronson & Rodrigues 859 (MO!). Ucayali: Prov. de Padre Abad, distrito de Padre Abad, carretera al. caserío San Miguel y Mapuya, 12-17 km de Aguaytía, bosque primario con abundante luz solar, 09°05'S; 075°26'W, 350 m, 8 Oct 2004, (♂ fl), Schunke & Graham 16307 (F n.v., MO!).

Figures

Figure 9. Geographic distribution of Curarea barnebyana, C. candicans, C. crassa, C. cuatrecasasii and C. gentryana.

Figure 11. Curarea barnebyana staminate plant: A flowering branch B detail of inflorescence C flower bud D inner sepal, adaxial surface E-F outer and inner petals, adaxial and abaxial surfaces G-H outer stamens, latero-adaxial and abaxial surfaces (based on Gudino et al. 952).

Figure 12. Curarea barnebyana pistillate plant: A inflorescence B flower C opened flower showing the petals and carpels D innermost sepal, adaxial surface E petal, abaxial surface F fruit, lateral surface. (A-E based on Ortiz & Vargas 200 F based on Dik 1213).