Gynochthodes leonardii Chavez, Venturina & Alejandro, 2015

Chavez, Jayson G., Venturina, Russell Evan L. & Alejandro, Grecebio Jonathan D., 2015, Gynochthodes leonardii: a novel species of Morindeae-Rubiaceae from Palawan, Philippines, Phytotaxa 222 (1), pp. 67-71 : 68-70

Gynochthodes leonardii Chavez, Venturina & Alejandro , sp. nov. (Figs. 1,2)

Gynochthodes leonardii can be distinguished from its close ally G. bartlingii by its sulcate and scatteredly scabrid and lenticelled branches; scarious and deciduous stipules; conduplicate petioles; 5–8 cm long, coriaceous leaves that are hispid to sparsely strigose underneath with acute to acuminate apex; 3 to 9 capitula in an inflorescence; hirsute calyx rims; short corolla tube that are hirsute on the outer surface.

Type:— PHILIPPINES. Palawan: Municipality of Narra, Mt. Victoria, along Trident Mining Company concession area, 24 May 2011, Pineda & Dimatatac 012 (holotype PNH!, isotypes USTH!, FEUH!).

Lianas. Branches sulcate, recurved, brown to gray, 2–3.5 mm in diameter, sparsely scabrid, lenticelled or excrescent, very flexible; branchlets paired at nodes, sulcate, ascending rarely porect, leaf bearing, short reaching to around 10 cm, scabrid turning puberulous towards the apex. Leaves opposite; petioles 4.5–9 × 0.3–1.4 mm, conduplicate, scabrid to strigose; lamina lanceolate or oblanceolate to elliptic, coriaceous, 4.71–8.27 × 1.05–2.38 cm, puberulent above, hispid to sparsely strigose and glandular along the margin underneath, acute to attenuate apex, cuneate to narrowly cuneate base, with 8–5 pairs of less prominent lateral veins, eucamptodromous. Domatia present on axils of secondary veins, with tuft hairs. Stipules oblong, fused into a conical tube, truncate at apex, scarious, shedding, 2.2–3 mm long, abaxially with sparse indument especially along the margin, adaxially with dense indumenta near the base; colleters numerous at base. Inflorescences terminal; peduncle 3.8–8.2 mm long, 0.5–1 mm in diameter, densely puberulent to almost puberulous; capitula 3–9 in umbel like cymes, with 6–13 sessile flowers distributed in upper 2/3 of capitulum. Flowers 4-merous, hermaphrodite or male. Calyx tube cupuliform, 0.8–1.9 mm long, 1.6–2.2 mm in diameter, acute or rounded to obtuse calyx teeth. Corolla tube 2.0– 3.6 mm long, outside hirsute turning puberulent towards the apex, upper 2/3 divided into four lobes, with dense long white hairs in upper half of the interior and corolla throat. Corolla lobes ovate, dull greenish yellow, puberulent at the apex. Stamens inserted at the upper half of the corolla tube; filaments <0.9 mm long; anthers 0.9–1.1 mm long, ligulate to oblong, white. Stigma bifid. Compound fruits sub-globose to oblate, 9.8–12.6 mm in diameter bearing 6–7 persistent calyx lobes, yellow-orange to fulvous when ripe, puberulous. Pyrene 5.2–6.4 x 2.9–4.1 x 1.6–2.5 mm, subglobose to ovoid with some being concavo-convex, with ridges, sparsely scabrid to strigose, oily, lacking air-filled cavity.

Paratypes:— PHILIPPINES. Palawan: Municipality of Aborlan, Iraan Mountains, 6 June 1950, Sulit 12538 ( PNH!) ; Municipality of Coron, Kingfisher Park , 12 April 2013, Suarez et al. 13224 ( USTH!) ; Municipality of Narra, Mt. Victoria, Trident Mining Company , 19 May 1984, Podzorksi 158442 ( PNH!) .

Distribution and Habitat:— G. leonardii is endemic to Palawan occurring on edges of open dry, ultramafic secondary forest patches or limestone schist along Trident Mining Co. concession area in Narra, at 150–700 m elevation; Iraan Mountains in Aborlan and Kingfisher Park, Coron.

Phenology:—Collected in flower and fruit from April to June.

Etymology:—The specific epithet is in commemoration of Leonard L. Co (1953–2010), a senior botanist of Conservation International-Philippines. His knowledge in plant taxonomy has provided inevitable contributions to facilitate understanding on the community structure of the Philippine flora.

Discussion:— Gynochthodes leonardii can be easily distinguished with other Philippine representatives with its highly variable leaf size and shape, and small flowers. Often, the leaves are elliptic and 8 cm long with apices that are acuminate, cuspidate or acute. It is noted that flowering materials of this species exhibit up to 9 capitula per inflorescence; however, fruiting branches only bear a maximum of four compound fruits. This distinct species shows a low level variation with G. bartlingii , but is different with the latter by its acute to attenuate leaf apices, hirsute corolla and calyx, with 3–9 capitula in an inflorescence.

Conservation Status:—This species is circumscribed on dry and open secondary forest patches of three localities considered as protected landscapes. In spite of this, construction of infrastructures in Palawan province to expand tourism, agriculture and the like may significantly reduce the limited number of G. leonardii individuals.

The georeference analysis reveals that the EOO for the species is 1,056.058 km 2 and an AOO of 16.000 km 2. Based on the guidelines and criteria of IUCN (2014), we propose to include this species under the category: Endangered, EN B1&2 ab(iii&v).