Nepenthes attenboroughii

Nepenthes attenboroughii

Languages: English

Overview

Comprehensive Description

Nepenthes attenboroughii is a montane species of insectivorous pitcher plant. It is named after the celebrated broadcaster and naturalist, Sir David Attenborough,[1] who is a keen enthusiast of the genus Nepenthes. The species is characterised by its large and distinctive bell-shaped lower and upper pitchers and narrow, upright lid (Robinson et al, 2009).

Author(s): Beck, Nicholas
Rights holder(s): Beck, Nicholas

Conservation and Management

Conservation Status

Robinson et al. (2009) assess this species as CR (Critically Endangered) according to the World Conservation Union (IUCN) Red List Criteria B2ab(v) (IUCN, 2001). They base their assessment on the species' limited distribution and its vulnerability to poaching.

Author(s): Schulz, Katja
Rights holder(s): Schulz, Katja

Description

Diagnostic Description

Overall Nepenthes attenboroughii is a terrestrial upright or scrambling shrub.(Robinson et al, 2009)

Stem The stem, which may be up to 3.5 cm thick, is circular in cross section and attains a height of up to 1.5 m.(Robinson et al, 2009)

Leaves The leaves are coriaceous and sessile or sub-petiolate. The leaves of rosettes are up to 30 cm long and 10 cm wide, whereas those of the scrambling stem are up to 40 cm long and 15 cm wide. The leaves are oblong to elliptic, obtuse at the apex and shortly attenuate at the base, clasping the stem by approximately two-thirds of its circumference and becoming decurrent for 2-3 cm.(Robinson et al, 2009)

Pitchers Nepenthes attenboroughii produces some of the largest pitchers in the genus, sometimes exceeding those of typical N. rajah in size, but is not known to have exceeded the size and volume records set by that species. The lower pitchers are brittle and campanulate (bell-shaped), up to 30 cm tall and 16 cm wide and emerge from tendrils that are 30-40 cm long and 4-9 mm in diameter. The tendrils are obviously flattened towards the leaf, making them almost semi-circular in cross section.(Robinson et al, 2009)

The upper pitchers are similar to the lower pitchers, but generally infundibular, to 25 cm tall and 12 cm wide.(Robinson et al, 2009)

Inflorescence Nepenthes attenboroughii has a racemose inflorescence up to 80 cm long. The male flower spike bears approximately 100 pedicellate flowers on a rachis up to 45 cm long and is recorded to bifurcate on occasion. The flowers lack bracts and produce red tepals that are broadly ovate with an obtuse apex.(Robinson et al, 2009)

The female inflorescence is shorter, to 65 cm long, never bifurcates, and bears up to 70 densely arranged flowers on a compact rachis up to 20 cm long. The tepals are brown to purple, ovate, and have an acute apex.(Robinson et al, 2009)

Author(s): Beck, Nicholas
Rights holder(s): Beck, Nicholas

Ecology

Distribution

The type specimen of N. attenboroughii was collected on the summit of Mount Victoria, an ultramafic mountain in central Palawan, the Philippines.(Robinson et al, 2009)

This species is known only from the summit area of Mount Victoria, Palawan, to which it is endemic. There, it grows among shrubs 0.8-1.8 m tall in relatively scattered populations of plants on rocky, ultramafic soil. It is not sympatric with other Nepenthes species.(Robinson et al, 2009)

Author(s): Beck, Nicholas
Rights holder(s): Beck, Nicholas

Trophic Strategy

Carnivory The pitchers of N. attenboroughii are open to the elements and thus often completely filled with fluid. This fluid is viscous in the lower part of the pitcher and watery above, forming two fractions that do not mix. The upper fraction supports populations of pitcher infauna, particularly mosquito larvae, and the pitchers of this species may benefit from both the usual capture of prey as well as the detritus produced by organisms living within the pitcher fluid.(Robinson et al, 2009)

Author(s): Beck, Nicholas
Rights holder(s): Beck, Nicholas

Evolution and Systematics

Systematics and Taxonomy

Nepenthes attenboroughii is closely related to the Palawan species, N. mantalingajanensis and N. mira, to N. peltata from Mindanao, and to N. rajah from Borneo.(Robinson et al, 2009)

The stated relationship of this taxon with species from Borneo and Mindanao agrees with observations made in the description of N. mira,(Cheek and Jebb, 1999) and is further supported in the type description of N. attenboroughii by paleogeographical evidence. Based on this evidence, the authors reason that these species, predominantly found growing on ultramafic soils on Palawan and Mindanao, are likely to have arisen as a result of the radiative speciation of a common ancestor in Borneo.(Robinson et al, 2009)

Author(s): Beck, Nicholas
Rights holder(s): Beck, Nicholas

References

Cheek, M., & Jebb M. (1999).  Nepenthes (Nepenthaceae) in Palawan, Philippines . Kew Bulletin. 54, 887-895.
IUCN (2001).  IUCN red list categories and criteria: version 3.1..
ROBINSON, ALASTAIR. S., FLEISCHMANN ANDREAS. S., MCPHERSON STEWART. R., HEINRICH VOLKER. B., GIRONELLA ELIZABETH. P., & PE√ĎA CLEMENCIO. Q. (2009).  A spectacular new species of Nepenthes L. (Nepenthaceae) pitcher plant from central Palawan, Philippines. Botanical Journal of the Linnean Society. 159, 195-202.
Wikipedia (2009).  Nepenthes attenboroughii. 2009,