Peperomia ekakesara Syam & S. Nampy, 2018

Radh, S. Syam & Nampy, Santhosh, 2018, Peperomia ekakesara: A new species of Piperaceae from Mathikettan shola National Park, Kerala, India, Phytotaxa 364 (3), pp. 283-288 : 284-287

publication ID	https://doi.org/ 10.11646/phytotaxa.364.3.8
persistent identifier	https://treatment.plazi.org/id/03E687B7-FFC5-FFE3-858D-FF0DFBCCFB2C
treatment provided by	Felipe
scientific name	Peperomia ekakesara Syam & S. Nampy
status	sp. nov.

Treatment

Peperomia ekakesara Syam & S. Nampy View in CoL sp. nov. ( Figs 1 View FIGURE 1 & 2 View FIGURE 2 )

The new taxon is morphologically close to P. heyneana Miq. (1846: 548) but can be easily distinguished by its glabrous, procumbent habit and having one stamen in each flower contrasting with pubescent, erect habit and two stamens in the latter.

Type:— INDIA. Kerala: Idukki district, Santhanpara, Mathikettan shola National Park, Sivanpara, ± 1610 m, 16 August 2016, S. Syam Radh & Santhosh Nampy 151707 (holotype CALI!).

Annual, epipetric, glabrous herb, 8–15 cm tall.Stem procumbent, branched dichotomously in zigzag manner,transparent, succulent, swollen at nodes. Leaves simple, alternate at the base, opposite or whorled towards apex, ovate to elliptic, 2.5–3 × 1.3–1.7 cm, with entire margins, obtuse to rounded at apex, cuneate to obtuse at base, both surfaces glabrous, rarely hairy at apex, adaxial surface dark green, with pellucid dots, abaxial surface pale green, fleshy; petioles 0.3–0.5 cm long, geniculate, glabrous; veins acrodromous, imperfect, basally 3-nerved; stipules absent. Flowers in terminal and axillary spikes; peduncles 1.5–4 cm long, glabrous, green; bracts peltate, margin wavy, 0.5 × 0.5 mm, glabrous, green, with a claw of 1.5 mm length at the base, glabrous, persistent. Flowers bisexual, inserted in the grooves on inflorescence axis, 0.75 × 1 mm, green. Stamens 1 in each flower, oriented towards left side; filaments 0.15 mm long, glabrous, white; anthers 0.25 × 0.25 mm, dithecous, dorsifixed, elliptic, white, dehiscing longitudinally, pollen white. Ovary green, superior, 0.5 × 0.25 mm, elliptic, glabrous; style absent; stigma forming a tuft of hyaline threads, arising from a groove, laterally, just below the top of ovary. Fruits globose to ovoid, attached in the pits of the infructescence, brownish, 1 × 1 mm, with sticky papillae on the surface. Seeds 1, adherent to the endocarp, albumen floury.

Etymology:—The epithet ‘ekakesara’ is derived from Sanskrit, ‘eka’ means one and ‘kesara’ refers to stamen, the whole referring to the monandrous condition.

Notes:—The presence of monandrous flowers distinguishes this species from all other species of Peperomia . To ascertain the distinctiveness of the monandrous condition, thirty plants belonging to three populations were critically examined and all flowers possessed only one stamen which arises from the basal part of the ovary, projecting towards the left side of each flower and arranged alternately on the inflorescence. The one stamen condition might be a derived character (apomorphic character) in this genus. Based on its morphology, Peperomia ekakesara can be classified in Peperomia subgenus Micropiper (Miq.) Miq. (1843: 45, 76), to which the morphologically similar species, P. heyneana Miq. also belongs.

Distribution & ecology:—Hitherto known only from the type locality. On wet rocks in the shola (stunted forests in valleys amid rolling grasslands), at an elevation about 1600 m.

Flowering & fruiting:—July to December.

Additional specimens examined (Paratypes):— INDIA. Kerala, Idukki district, Santhanpara, Mathikettan shola National Park , Sivanpara , ± 1610 m elevation, 16 August 2015, S. Syam Radh & Santhosh Nampy 149196 ( CALI!) ; way to Mannakkudy , 10 October 2016, Santhosh Nampy & S. Syam Radh 191101 ( CALI!) .

Conservation status:— More than 100 individuals in three populations are found in the park and the species falls under the category Near Threatened (NT) based on IUCN criteria ( IUCN 2001 & 2010).