Helietta hirsuta H. Cuadros, 2023

Cuadros, Hermes, 2023, A new species of Helietta (Rutaceae, Pteleinae) from Colombia, Phytotaxa 585 (2), pp. 154-160 : 155-157

Helietta hirsuta H. Cuadros , sp. nov. ( Figures 1 , 2 )

Type:— COLOMBIA. Dept. de La Guajira: Mun. de Albania, Complejo minero El Cerrejón, Área de Compensación La Bahía , elev. 216 m, 11°09’17.9” N, 72°37’38.9” W, 22 November 2012 (fl. & fr.), H. Cuadros 6407 (holotype DUGAND!; isotypes (to be distributed): COL!, HUA!, JAUM!, MEDEM!, MO!) .

Diagnosis:— Helietta hirsuta H. Cuadros resembles H. plaeana by the mature glabrous leaves, canaliculate petiole and terminal leaflets longer than the laterals, but in H. hirsuta the fully developed inflorescence is longer than the leaves, the axis of the inflorescence and the pedicels are pubescent (versus glabrous or with small trichomes in H. plaeana ); H. hirsuta also differs from H. plaeana by having consistently 4-lobed sinuate nectar disk (vs. 4(–5)-lobed disk), tetramerous flowers (vs. 4(–5)-merous), pedicel pubescent (vs. glabrous) and puberulous mericarps (vs. glabrous mericarps); glandular-punctate and ciliate petals (vs. entire petals) and tuberculate ovary with hirsute hairs (vs. lobed and glabrous ovary).

Shrub or tree 2–15 m tall; shoots pale brownish with many rounded lenticels, terminal buds and young twigs densely pubescent. Young leaves pubescent, the mature ones glabrous or hispid; petiole 2–3 cm long, pubescent, canaliculate adaxially; leaflets chartaceous, consistently sessile, pellucid punctate on both surfaces, with some hirsute hairs, narrow elliptic, revolute at margin, acute at apex, cuneate at base, the lateral leaflets smaller than the terminal leaflets, terminal leaflets 4.6–6.7 × 1.9–2.6 cm, lateral leaflets 2.9–5.8 × 1.1–2.3 cm; midvein prominent on both surfaces. Inflorescence a terminal diplothyrse longer than the subjacent leaves (ca. 10 cm long), pubescent; peduncle ca. 0.5 cm long; coflorescences 6–18, opposite, 2–6 cm long; bracts cuspidate, ciliolate. Flowers 4-merous; pedicel pubescent, ca. 1 mm long, bractlets deltoids, pubescent, ciliolate; sepals ovate, imbricate, pubescent, with ciliate margin, ca. 0.73 × 0.71 mm; petals yellow-cream, pellucide-punctate, ciliolate, ca. 2.2 × 1 mm; stamens 4, ca. 1 mm long; anthers with linear dehiscence; disk with 4-unequal lobes; ovary semiglobose, tuberculate, with stiff hairs; style canaliculate; stigma cream, slightly 4-lobed. Fruits of 4-mericarps with hirsute hairs, glabrescent to glabrous at maturity, mature fruit 2.8 × 0.6–1 cm.

Additional Specimens Examined (paratypes):— COLOMBIA. Dept. de La Guajira: Mun. de Albania, Cerrejón , elev. 220 m, 12 March 1981 (st.), P. Bunch s.n. ( UDEA); Cerro La Represa. Vía Chorreras – Caracolí , N.v. Marambito , 25 October 1987 (fl. & fr.), G. Mahecha 5077 & G. Jiménez ( UDBC); Fonseca – Distracción, Sitio Las Casitas – El Socorro, bosque a 2 km, elev. 500 m, 10º30.576 N, - 72º59.24 W, 31 August 1990, O. Marulanda 2107 ( UDEA); Mun. de Albania, Complejo minero El Cerrejón, Área de Compensación Aguas Blancas-Santa Helena , elev. 300 m, 11°08’4.2” N, 72°39’37” W, 13 January 2022 (fr.), H. Cuadros 6986 ( DUGAND) .

Etymology:—The epithet hirsuta refers to the ovary with evident stiff hairs ( Figure 1A ).

Vernacular name:— H. hirsuta is called “marambito” by local people.

Phenology:—Flowers and fruits has been observed from the middle October until the end of January.

Distribution and habitat:— H. hirsuta has been recorded at the Caribbean coast of Colombia ( Fig. 3 ), which is characterized by a long dry period of six to eight months without rain and heaviest rains between October–December, in areas with dry forest between 220 and 350 m elev., calcareous soils, characterized by the presence of common species like Aspidosperma polyneuron M̧ller Argoviensis (1860: 57), Sideroxylon obtusifolium ( Roemer & Schultes 1819: 802) T.D. Pennington (1990: 114) , Bursera simaruba ( Linnaeus 1753: 1026) Sargent (1890: 260) , Hippocratea volubilis Linnaeus (1753: 1191) , Machaerium arboreum ( Jacquin 1760: 27) Bentham (1837: 63) , Lachesiodendron viridiflorum ( Kunth 1821: 81) P.G. Ribeiro, L.P. Queiroz & Lucklow (in Ribeiro et al. 2018: 45), and Pseudobombax septenatum ( Jacquin 1760: 26) Dugand (1943: 65) . Is known in the department of La Guajira from the type locality and from two records from the municipality of Distracción, but probably it can be collected in other Colombian Caribbean localities.

Taxonomic considerations:—Taking into account the detailed descriptions made by Pirani (1998), Helietta hirsuta differs from other species like H. parvifolia (A. Gray ex Hemsley 1878: 5) Bentham in Hooker (1882: 66) by its terminal leaflets twice as long as the lateral and ovary densely white-pilose with short trichomes; from Helietta lottiae F. Chiang (1984: 455) by its pilose ovary combined with apiculate anthers; from Helietta lucida Brandegee (1911: 182) by its pubescent ovary combined with the yellowish raised veins of the leaflets and from Helietta puberula R.E. Fries (1907: 1001) by the inflorescence shorter than the leaves, pentamerous flowers and 5-lobbed, glandular tuberculatepuberulous ovary ( Pirani, 1998).

Figures

FIGURE 1. Helietta hirsuta H. Cuadros. A. Flower with ciliate petals and ovary with hirsute hairs. B. Schematic drawing from photo A, C. Young mericarp with hirsute hairs, D. Petal ciliolate, glandular-punctate. Scale bar 1mm. Photos and draws by Conchita Pinzón-M.

FIGURE 2. Helietta hirsuta H. Cuadros. Holotype.

FIGURE 3. Helietta hirsuta H. Cuadros. A. Type locality, B. Habitat