Cestrum amistadense A.K.Monro, 2012

Monro, Alex K., 2012, Eight new species of Cestrum (Solanaceae) from Mesoamerica, PhytoKeys 8, pp. 49-82 : 51-53

Cestrum amistadense A.K.Monro sp. nov. Figs 1 A-D 2 A-C

Diagnosis.

Most similar to Cestrum langeanum D’Arcy from which it can be distinguished by the shiny upper leaf surface that is characteristically shrunken around the primary and secondary veins, the raised quaternary and quinternary veins on the upper leaf surface, the glabrous peduncle and the longer inflorescence.

Type.

Panama. Bocas del Toro: La Amistad Binational Park, La Pata del Cedro camp, ca. 1750 m, 09°04'27"N, 82°44'17W (DMS), 11 Mar 2004, A. K. Monro & E. Alfaro 4328 (holotype: PMA; isotypes: BM000849623, INB).

Description.

Shrubs, 0.4-2.0 m. Leaf-bearing stems drying brown, yellow-brown or olive green, the internodes 25-55 × 1.375-4.0 mm; young stems glabrous. Axillary buds 0.5-1.0 mm, drying dark brown to brown, sparsely pubescent or glabrous, not subtended by a minor leaf. Lamina 90-225 × 26-100 mm, length to width ratio 2.1-3.5, oblong-ovate, ovate, ovate-elliptic, elliptic, or lanceolate, coriaceous, drying yellow-green, brown or dull olive green above, paler below; the upper surface glabrous, primary to quarternary veins, (occasionally primary and secondary only) raised and clearly visible to the naked eye; the lower surface glabrous, primary and secondary, primary to tertiary or primary to quinternary veins raised and clearly visible to the naked eye, secondary veins 6-13 pairs, borne 65-80° to the midrib, irregularly and weakly curved, decurrent, the veinlets visible or not, where visible unbranched or branched; base obtuse to decurrent or asymmetrically acute-cuneate, obtuse, or decurrent; margin entire; apex subcuspidate to cuspidate or acute; petioles 7-25 × 1.25-2.50 mm, drying green, dark brown or yellow-brown, glabrous. Inflorescences 1-3 per herbarium sheet, terminal or subterminal panicles, axillary panicles solitary in each axil, ca. 105 mm long, bearing 7-21 flowers borne in 2-6 clusters, each cluster bearing 3 or 4 flowers; peduncle 25-37 × 1.0-1.5 mm, drying green-brown, yellow-brown or brown, glabrous; bracts 3-100 × 0.75-31.0 mm, leaf-like to bracteole-like; bracteoles 3.0-3.5 mm, linear, glabrous. Flowers pedicellate, the pedicels 0.50-0.75 mm; calyx 3.25-4.50 × 2.0-2.25 mm, the outer surface glabrous, the lobes 5, 0.50-0.675 mm, erect; corolla pale purple to lilac, 26-34 mm long, the tube 26-28 mm long, 3.0-3.5 mm in diameter at the mouth, ca. 1.25 mm in diameter at the base, glabrous, the lobes 5, 6.5-8.0 mm long; stamens 5, the filaments 23.5-26.0 mm long, equal, adnate for 19.0-20.5 mm of their length, glabrous, a lobe-like appendage present at insertion point, the anthers ca. 1 × 0.675-0.750 mm; style 24.5-26.0 mm, the stigma 0.375-0.50 × 0.75-1.25 mm. Infructescences 25-80 mm long, bearing 5-12 fruit; fruiting calyx 3.5-4.0 × 7-8 mm; fruit not seen.

Etymology.

From the locality of the holotype, La Amistad Binational Park in Costa Rica and Panama.

Distribution.

Premontane, montane, cloud and oak forest from 900 m to 2100 m. Collection notes indicate that this species is restricted to undisturbed or ‘high’ forest. Existing collection localities suggest that Cestrum amistadense is distributed over an area of ca. 7,360 km2 of the Fila Costeña and the Talamanca Mountains in eastern Costa Rica and western Panama ( Google Earth, accesssed April 21 2011, images from 2011).

Discussion.

Of the six known collections of Cestrum amistadense , none had been previously determined to species. Comparison of the holotype and paratype material with type specimens from the herbaria listed in the Materials and methods section recovered Cestrum amistadense as most similar to Cestrum langeanum D’Arcy and Cestrum longiflorum Ruiz & Pav. It can be distinguished from those speciesby the presence and distribution of pubescence, leaf surface, venation and inflorescence morphology as summarised in Tables 1 and 2 .

Conservation status.

Using IUCN criteria ( IUCN 2001) Cestrum amistadense is considered Vulnerable based on subcriteria B: Extent of Occurrence <20,000 km2 (B1), a severely fragmented range and small number of collection localities (B1a) and continuing decline in the area of habitat due to the conversion of forest to agricultural land (B1b).

Paratypes.

COSTA RICA. Limón: Cantón de Talamanca, Bratsi, Amubri, Alto Lari, Kivut, siguiendo la fila divisoria entre Ríos Lari y Dapari, cuenca superior de ambos, 09°22'45"N, 83°06'15"W (DMS), 1900 m, 24 Mar 1992, B. Hammel 5474 (INB, MO); Puntarenas: Cantón de Osa, Río Piedras Blancas, junto a la casa, faldas Cerro Anguciana, Fila Cruces, 900 m, 08°49'02"N, 83°11'23"W (DMS), 9 Dec 1993, R. Aguilar, D. Gómez, M. Grayum & B. Hammel 2732 (BM, INB). PANAMA. Bocas del Toro-Chiriquí border: end of Río Palo Alto road to Chiriquí border with Bocas del Toro, near peak of Cerro Macho, 08°49'N, 082°23'W (DMS), 2200 m, 20 Nov 1978, B. Hammel 5799 (MO); La Amistad Binational Park, Quebrada by Campamiento Lucio, 09°05'03"N, 082°45'44"W (DMS), 1850 m, Mar 16 2004, A. K. Monro & E. Alfaro 4415 (INB, MO, PMA); Chiriquí: end of road past Palo Alto northeast of Boquete 2100 m, 8 Feb 1979, B. Hammel 6062 (MO); trail to Cerro Pate Macho, headwaters of the Río Palo Alto, above Palo Alto, 1700-2100 m, 08°47'N, 82°22'W (DMS), 24 Apr 1982, S. Knapp & R. Schmalzel 4766 (MO).

Figures

Figure 1. Cestrum amistadense A. K. Monro A Flowering stem B Flower C Longitudinal section through the corolla showing stamen arrangement D Style. Drawn from A. K. Monro & E. Alfaro 4328 (BM).

Figure 2. Cestrum amistadense A. K. Monro A Habit. B. Inflorescence C Flowers. A. K. Monro & E. Alfaro 4415 (Photo A. K. Monro 2004).