Nepenthes eymae

Species of pitcher plant from Sulawesi

Nepenthes eymae /n//ᵻ/'/p//ɛ//n//θ//iː//z// /'/eɪ//m//aɪ/ is a tropical pitcher plant endemic to Sulawesi in Indonesia, where it grows at elevations of above sea level. It is very closely related to N. maxima, from which it differs in its wine glass shaped upper pitchers. The specific epithet eymae honours Pierre Joseph Eyma, a Dutch botanist who worked extensively in the Dutch East Indies and who originally discovered the species.

Nepenthes eymae was discovered in central Sulawesi by Dutch botanist Pierre Joseph Eyma in 1938. Eyma's original material of this species includes the herbarium specimen Eyma 3968, which bears a male inflorescence. The holotype, designated as Kurata, Atsumi & Komatsu 102a, was collected on the northern spur of Mount Lumut in Central Sulawesi, at an altitude of 1850 m, on November 5, 1983. Despite this, the species name is valid per Article 37 of the International Code of Botanical Nomenclature, and Kurata's description includes an illustration of the holotype on page 44. and "Nepenthaceae" (2001), In Pitcher Plants of the Old World, McPherson wrote that "the specific status of N. eymae seems warranted since the two taxa [N. eymae and N. maxima] appear to occur both together and in isolated, self sustaining communities".

Nepenthes eymae is a climbing plant growing to a height of up to 8 m. The two lobes of the peristome are typically separated by a gap of several millimetres under the lid. The peristome ribs are well developed, being up to 2 mm high. The pitcher lid or operculum is ovate to triangular, growing to 5 cm in length by 3 cm in width. They may be shortly contracted directly below the orifice. As for the majority of studied highland Nepenthes (but not lowlanders), this value differed significantly (P < 0.001) from that of distilled water, leading the authors to categorise N. eymae as a viscoelastic species. Nepenthes eymae is very closely allied to the extremely polymorphic N. maxima, which is widespread across Sulawesi, New Guinea, and the Maluku Islands. It differs from this species in its wingless, infundibular and relatively small upper pitchers, ovate lower pitchers, and hastate lid. While some forms of N. maxima also produce entirely infundibular aerial traps, these are not usually as abruptly contracted (and therefore wine glass shaped) as in N. eymae, and may or may not have fringed wings. Where the two species grow side by side, introgression may blur these morphological boundaries and make circumscription difficult. Like N. eymae, N. maxima and N. klossii (another closely related species) also commonly have two lid appendages. Nepenthes fusca of Borneo may produce aerial pitchers resembling those of N. eymae, although its lower pitchers are considerably narrower and cylindrical in shape. The lower pitchers of N. eymae could potentially be confused with those of another Bornean endemic, N. veitchii, although otherwise these species have little in common, particularly with respect to the upper pitchers.