Nepenthes danseri, Jebb & Cheek (Jebb & Cheek, 1997

Cheek, M., 2015, Nepenthes (Nepenthaceae) of Halmahera, Indonesia, Blumea 59 (3), pp. 215-225 : 223

The Nepenthes danseri group

Among the SE Asian paniculate species of Nepenthes , N. weda and N. halmahera appear to form a natural, morphologically coherent and probably monophyletic group with N. danseri . All three are set apart by sharing simple, straight, acute, multicellular hairs which are also shared with the basal Indian Ocean paniculate species ( Jebb & Cheek 1997, Mullins & Jebb 2009). Other paniculate Nepenthes species have branched or stellate hairs. A second feature uniting these three species are the leaves of the climbing stems, which have moderately broad blades contracting into ± well-defined canaliculate-winged petioles. These petioles broaden abruptly at the junction with the stem, partly girdling it with a broad patent wing which equally abruptly becomes very shortly- to long-decurrent, depending on the species. This abrupt widening of the petiole at the node, together with patent wings, and a red colouration of the petiole midrib area and stem, are most distinctive, and appear to represent apomorphies which are otherwise unknown in the genus. Thirdly, these three species, uniquely among all paniculate species, share the characteristic of having only 15– 30(– 50) lower surface lid nectar glands which are large ((0.2 –)0.5 – 1.25 mm diam) with overarching borders, rather than having hundreds of minute nectar glands which have erect, non-overarching bordering walls. However, outside the paniculate group, such nectar gland characteristics can be found in N. gracilis Korth. (Malaysian Peninsula to Borneo and Sumatra) which has even fewer, larger, more strongly overarched glands.