Anthurium huaytae Croat & C.Martel, 2023

Martel, Carlos & Croat, Thomas B., 2023, A new Species of Anthurium section Calomystrium, subsection Rupicola (Araceae) from Peru, Phytotaxa 585 (3), pp. 225-232 : 226-230

Anthurium huaytae Croat & C.Martel , sp. nov. ( Figs. 1–2 )

Most similar to Anthurium amnicola Dressler , but differing by its epiphytic habit (vs. epipetric habit in A. amnicola ), white or light lavender spathe (vs. purple spathe in A. amnicola ), persistent cataphylls (vs. promptly deciduous cataphylls in A. amnicola ) and slimmer flowers in relation to its length (ratio 1:1.1) (vs. flowers with a length-width ratio of 2: 3 in A. amnicola ). Also similar to Anthurium antioquiense Engl. , but differing by its epiphytic habit (vs. lithophytic habit in A. antioquiense ), narrowly ovate spathe (vs. lanceolate in A. antioquiense ) and the 5 primary lateral veins on either side of the midrib (vs. 3–4(6) primary lateral veins on either side of the midrib in A. antioquiense ).

Type:— PERU: Pasco: Province of Oxapampa, District of Chontabamba, Marquizo , SW of Oxapampa, flowered in cultivation, cultivated by Abel Huayta, 1825 m elevation, 02 August 2022, C . Martel , T. B . Croat & A . Huayta 151 (holotype HOXA! [ Accession 80405], isotypes MO!, K!) .

Epiphytic herb to less than 30 cm high; internodes short, 4.0– 7.5 mm long, 0.5–1.0 cm diam.; cataphylls 3.5–6.5 cm long, persisting green and intact at upper internodes, eventually brownish, somewhat broken up but not fibrous; petioles 7–13 cm long, 4–5 mm diam., subterete, medium green, semi-glossy, with an obscure narrow sulcus adaxially; leaf blades narrowly elliptic to lanceolate, 14–17 cm × 4–6 cm, three times longer than broad, two times longer than petioles, subcoriaceous, dark green and glossy above, light green below, attenuate apex, cuneate at base; midrib narrowly rounded and paler above; primary lateral veins 5 pairs, arising from below the middle, spreading at 27º angle; collective veins 1 pair, arising from the base, 8–10 mm from margins midway. Inflorescence erect, 18–28 cm long; peduncle 13–25 cm long, terete; spathe spreading and weakly reflexed, narrowly ovate, white (weakly tinged with lavender) or light lavender, matte on the inner surface, semi-glossy on the outer surface, inserted at 45º angle on peduncle; spadix stipitate (stipe 7–9 mm pale green), terete, 1.7–2.4 cm long, 3.5–4.5 mm diam., lavender-violet, semi-glossy; flowers 6–7 per spiral, 2.0–2.2 × 2.3–2.6 mm, sub-rhombic to weakly 4-lobed; lateral tepals 1.0–1.2 × 0.8–1.0 mm, subtriangular to pentagonal, inner margin broadly rounded, outer margin 3-sided; pistils with stigma weakly protruding, whitish; stamens not seen. Infructescence not observed.

Phenology:— In cultivation, the species flowered several times throughout the year.

Distribution, habitat, and ecology:— Anthurium huaytae is known from a single locality in the wet montane forests of central Peru ( Fig. 3 ). Different from the other nine species of subsect. Rupicola that cling to rocks in streams, A. huaytae was found growing as an epiphyte on a tree. The floral traits associated with A. huaytae are congruent with those of some plants pollinated by male euglossine bees ( Williams & Whitten 1983; Gerlach & Schill 1991), such as colour (the lavender-violet spadix) and floral scent composition (see below), which gather perfumes from flowers and other sources.

Ten chemical compounds were detected in the scent bouquet of the A. huaytae inflorescence ( Table 1 ). Terpenoids are best represented with eight compounds followed by one aromatic and one aliphatic compound. The compounds 1,8-cineole and benzyl acetate were the dominant representing more than 90% of the total emitted scent ( Table 1 ). Both main compounds are common among male euglossine pollinated aroids ( Diaz Jiménez et al. 2019) and specifically 1,8-cineole has been identified in some male euglossine-pollinated Anthurium ( Hentrich et al. 2010) .

Conservation Status:— Anthurium huaytae is known from a single locality, where a few specimens have been spotted. However, since some areas near the type locality (e.g. areas in Yanachaga–Chemillén National Park and Bosque Sho’llet Conservation area) have similar ecological conditions, more individuals of other populations may potentially exist. Thus, its conservation status cannot be assessed at this time and must be classified as data deficient (DD) according to the IUCN (2022) criteria.

Eponymy:— The species is named in honour of Abel Huayta, a nurseryman and orchid enthusiast from Oxapampa who made the first collection and successfully propagated the species.

Notes:— Anthurium huaytae is the first report of the subsect. Rupicola for Peru, extending the occurrence of the subsection to the south in more than 1000 km in a straight line ( Fig. 3 ). All the other nine species of subsect. Rupicola occur in the rain and montane forests of Colombia, Ecuador and Panama, most showing a rather restricted distribution ( Fig. 3 ). Anthurium huaytae is characterized by its moderately small habit, short internodes, intact cataphylls, terete petioles, oblong-elliptic blades with two basal veins serving as the collective veins, two primary lateral veins moderately remote from the margin, a moderately pedunculate inflorescence with narrowly ovate, spreading-reflexed, white spathe and a stipitate lavender-violet spadix. Furthermore, A. huaytae is so far the only Anthurium species of subsect. Rupicola that grows as an epiphyte in contrast to the others that are adapted to grow on rocks. The new species is most similar to Anthurium amnicola Dressler (1980: 55) from Panama, which might be its closest relative. They both share rather elliptic blades, a violet spadix tapered toward the apex, the spathe inserted at a 45° angle on the peduncle, and a relative short spadix compared to the spathe. Anthurium huaytae is also similar to Anthurium antioquiense Engler (1905: 174) and they both share the persistent cataphylls and the lavender spadix.

Figures

FIGURE 1. Anthurium huaytae. A. Plant habit, plant growing in a pot. B. Peduncle, spadix and spathe. C. Inflorescence, showing details of the flowers. Photographs by C. Martel.

FIGURE 2. Anthurium huaytae. Herbarium type specimen (Martel et al. 151, HOXA!). Photograph by Rocio Rojas. Reproduced with permission.

FIGURE 3. Distribution map of the Anthurium species of the section Calomystrium subsection Rupicola (based on Croat et al. 2007). Prepared by Roxana Rojas.