Nepenthes robcantleyi, or Robert Cantley's pitcher plant,Nepenthes robcantleyi (Robert Cantley's pitcher plant). Royal Botanic Gardens, Kew. is a tropical pitcher plant endemic to the Philippine island of Mindanao. It is closely allied to N. truncata and was once considered a dark, highland form of this species.Mey, F.S. 2011. Nepenthes robcantleyi aka "Nepenthes black truncata". Strange Fruits: A Garden's Chronicle, December 27, 2011. Nepenthes veitchii from Borneo is also thought to be a close relative.
The pitchers of N. robcantleyi are exceptionally large, reaching 40 cm in length by 10 cm in width. The inflorescence, at up to 2.5 m long, is the tallest among known Nepenthes species.Smith, L. 2011. The award-winning plant that dines on rats and reptiles. The Independent, December 26, 2011. The plant itself does not grow very tall, however, and is not known to climb.
The specific epithet robcantleyi honours Robert Cantley, who was involved in the plant's discovery, propagation, and introduction to cultivation.McPherson, S.R. 2011. Discovery of Nepenthes robcantleyi. In: New Nepenthes: Volume One. Redfern Natural History Productions, Poole. pp. 452–457.
Botanical History
Discovery Nepenthes robcantleyi was discovered by Robert Cantley in January 1997, on a remote mountain on the island of Mindanao in the Philippines. Cantley was exploring the site in search of N. truncata seeds for his recently established plant nursery, Borneo Exotics. The site lay within a logging concession and Cantley was accompanied by the head of security for the company with the logging rights to the area.
Near the top of a small hill Cantley found a number of typical N. truncata plants as well as two mature individuals of a striking, previously unknown taxon. Though bearing very dark pitchers with well-developed wings and a wide, flared peristome, the plants closely matched N. truncata in leaf morphology and were at the time assumed to represent a robust highland variant of this species. One of these plants bore a mature infructescence that had already dispersed "nearly all" of its seeds. Cantley collected the few remaining seeds from this plant. The darker of the two plants—which later became known as the "black N. truncata" on account of its almost completely black pitchers—was growing in full sun and measured around 1.5 m in diameter, being "not yet mature".
The original population discovered by Cantley is now thought to be extinct, as the area was cleared shortly after Cantley's visit (in 1997) and two trips in the subsequent two years failed to find any surviving plants.
Horticultural Interest The seeds collected by Cantley were successfully germinated in cultivation. The resulting plants closely matched the two individuals seen in the wild in both their morphology and dark pigmentation (though they exhibited some variation in peristome colour). Initially thought to represent an extreme variant of N. truncata, they were presented as such on the Borneo Exotics website.Nepenthes truncata. Borneo Exotics. [archived page from 6 October 2008]
Martin Cheek's describing paper states that only 9 plants were raised from the original batch of seeds. Cantley subsequently clarified that there were in fact 11 plants: 4 were sent to a grower in the United States (Tony Paroubek),Cantley, R. 2012. Nepenthes robcantleyi: Tony Paroubek's Clones . Borneo Exotics. 1 to a grower in Japan (Shinya Yamada),Cantley, R. 2012. Nepenthes robcantleyi: Shinya Yamada's plant . Borneo Exotics. and 6 remained at Borneo Exotics.Cantley, R. 2012. Carnivorous Plants in the tropics, March 17, 2012. Of the four US plants, two were later stolen and one of the remaining two grew for only a short time before dying; this latter specimen may have been of hybrid origin.Paroubek, T. 2012. Re: black truncata: a new species? Carnivorous Plants in the tropics, March 25, 2012.
The six Borneo Exotics plants form a "Royal family" that includesCantley, R. 2012. Carnivorous Plants in the tropics, March 25, 2012. the 'Queen of Hearts',Cantley, R. 2012. Nepenthes robcantleyi: 0136-51 'Queen of Hearts' . Borneo Exotics. 'King of Clubs', Cantley, R. 2012. Nepenthes robcantleyi: 0136-54 'King of Clubs' . Borneo Exotics. 'King of Spades',Cantley, R. 2012. Nepenthes robcantleyi: 0136-55 'King of Spades' . Borneo Exotics. an unnamed female,Cantley, R. 2012. Nepenthes robcantleyi: 0136-53 female . Borneo Exotics. and two unsexed plants.Cantley, R. 2012. Nepenthes robcantleyi: 0136-52 unsexed . Borneo Exotics.Cantley, R. 2012. Nepenthes robcantleyi: 0136-56 unsexed . Borneo Exotics. The 'Queen of Hearts' and 'King of Spades' were crossed when they flowered together in cultivation and their progeny sold by Borneo Exotics, becoming the source of practically all cultivated specimens of this species. In total around 3,000 seedlings were produced. They became available commercially in late 2009.
Nepenthes robcantleyi, and particularly the 'Queen of Hearts' plant, has featured prominently in the company's Gold Medal-winning Chelsea Flower Show displays.Fernando, H. 2007. Borneo Exotics wins another gold at Chelsea. The Sunday Times (Sri Lanka), June 3, 2007. Borneo Exotics strikes gold for the third time at Chelsea Flower Show. The Sunday Times (Sri Lanka), May 30, 2010. Fernando, H. 2011. Lanka’s Borneo Exotics blooms again at Chelsea Flower Show. The Sunday Times (Sri Lanka), May 29, 2011. It has also appeared at other shows, including the Singapore Garden Festival in 2008.
The species is reported to be an easy grower and to do well in typical Nepenthes highland conditions, with warm days up to 25 °C, cool nights down to 12 °C, and high light levels. Providing adequate conditions are maintained, a pitcher-to-leaf size ratio greater than 1 can be achieved in cultivation. A number of horticultural hybrids involving N. robcantleyi have been produced.2012 Nepenthes Roundup. Borneo Exotics. [Anonymous] 2013. New & returning items - summary. Nepenthes Growers Newsletter 2(3): 3. [Anonymous] 2014. New items - summary. Nepenthes Growers Newsletter 3(1): 3.
Formal Description Nepenthes robcantleyi was formally described by Kew botanist Martin Cheek in the Nordic Journal of Botany. An independently paginated preprint of the type description was distributed on 2 December 2011, but the journal number in which it appeared was only issued on 6 January 2012 (though dated "2011"). For the purposes of priority the year of valid publication is recorded as 2011.
The specific epithet robcantleyi was chosen to honour Robert Cantley. The shorter epithet cantleyi (also referring to Robert Cantley) had previously been applied to a natural hybrid between N. bicalcarata and N. gracilis (N. × cantleyi). Though this name has never been validly published (it is a nomen nudum)Schlauer, J. N.d. Nepenthes cantleyi. Carnivorous Plant Database. and was therefore available for describing a new species, Cheek chose robcantleyi instead to avoid confusion between the two.
The herbarium specimen Cheek 15877 is the designated holotype and is deposited at the Royal Botanic Gardens, Kew (K) in London, England. An isotype is held at the Philippine National Herbarium (PNH) in Manila, the Philippines. Cheek 15877 was prepared on 15 June 2010, and originates from cultivated material that was grown from wild seed originally collected by Cantley in 1997.Nepenthes robcantleyi Cheek. International Plant Names Index (IPNI). This herbarium material was prepared from the 'Queen of Hearts' plant, which was supplied by Cantley. Cantley also supplied Cheek with closeup photographs of the other mature specimens in his possession, and a photographic record from January 1997 (showing the original wild plants) is deposited alongside the herbarium material.
Possible Rediscovery Wild plants resembling N. robcantleyi were found by Andy Smith and colleagues in 2011, but due to their epiphytic habit they could only be photographed at a distance.Smith, A. 2011. Carnivorous Plants in the tropics, December 27, 2011. Smith, A. 2011. Dark epiphytic N. truncata 2. Flickr. Smith managed to relocate the plants in 2013, and this time he was able to examine them more closely, showing that they were morphologically similar to N. robcantleyi and possibly conspecific with it.Mey, F.S. 2013. Looking for Nepenthes robcantleyi in Mindanao, Philippines. Strange Fruits: A Garden's Chronicle, September 13, 2013.
In 2012, Wally Suarez encountered similar plants at an unspecified locality in Mindanao. Like those found by Andy Smith, these plants grew exclusively as epiphytes.Suarez, W. 2014. Re: black truncata: a new species? Carnivorous Plants in the tropics, June 27, 2014. Suarez, W. 2014. Re: black truncata: a new species? Carnivorous Plants in the tropics, July 2, 2014. Suarez, W. 2014. Re: black truncata: a new species? Carnivorous Plants in the tropics, July 10, 2014. Mansell, G. 2014. Re: black truncata: a new species? Carnivorous Plants in the tropics, July 14, 2014.
Description Nepenthes robcantleyi is a shrub growing to a height of 0.5–1 m; no climbing specimens have been recorded. The stem is terete and reaches around 2 cm in diameter in mature plants, with internodes 1.5–2.5 cm long. The short internodal length means that each leaf base forms a slight sheath around the one immediately above it. Axillary buds are inconspicuous.
Leaves Leaves are thick and robust, with a coriaceous (leathery) texture, and possess a distinct petiole. Laminae (leaf blades) borne on short stems are oblong-elliptic and measure up to 28.5 by 26.5 cm. The laminar apex is both truncate and acuminate, the acumen continuing for 2–3 cm down the tendril and being similarly wide. The tendril attachment is not peltate. The laminar base is cordate with a sinus 2.1–3.2 cm deep. The petiole is highly pronounced and very long, reaching 23 cm in length. It varies in width from 0.8–1.0 cm near the lamina to 2 cm in its basal portion. It is canaliculate with wings that fold over the adaxial channel; this gives the petiole its terete appearance. The base of the petiole forms a sheath that surrounds the stem for three-fifths of its circumference and 3–5 cm of its length. Two to four prominent longitudinal veins are present on either side of the midrib. Pinnate veins are inconspicuous. Tendrils are thick (≤7 mm in diameter) and uncoiled, even when produced on higher parts of the stem.
Pitchers