Charles Clarke

From Carnivore to Detritivore? Isotopic Evidence for Leaf Litter Utilization by the Tropical Pitcher Plant Nepenthes ampullaria

Nepenthes pitcher plants trap prey in specialized leaves formed into pitchers. Most lowland species live in open, sunny habitats and capture prey to obtain nutrients, principally nitrogen (N). Nepenthes ampullaria is commonly found under closed canopy forest and possesses morphological traits that indicate adaptation to trap leaf litter as a nutrient source. We tested this hypothesis by comparing foliar stable N isotope abundance (δ15N) between plants growing under forest canopy at 20 sites (litterfall present) and those growing in 20 open areas (no litterfall) in Borneo. Foliar δ15N values were significantly lower and total N concentrations were higher for the plants with access to litterfall. Using a mixing model, we estimated that N. ampullaria plants growing under forest canopy derived \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape

Nepenthes baramensis (Nepenthaceae) – a new species from north-western Borneo

35.7\% \pm 0.1\%

Climate, soils and vicariance - their roles in shaping the diversity and distribution of Nepenthes in Southeast Asia

\end{document} of their foliar N from leaf litter inputs.

Potential effects of climate change on members of the Palaeotropical pitcher plant family Nepenthaceae

Localized ultramafic outcrops in Kinabalu Park (encompassing Mount Kinabalu and Mount Tambuyukon) in Sabah (Malaysia) are known for high levels of plant diversity and endemism, which have been stimulated by extreme soil chemistry and biogeographic factors, such as isolation. Characteristic of these outcrops are edaphic endemics of insectivorous pitcher plants from the Nepenthaceae-family including Nepenthes burbidgeae, N. edwardsiana, N. macrovulgaris, N. rajah and N. villosa, all of which (except N. macrovulgaris) are confined solely to the protected area of Kinabalu Park. Although the various aspects of plant taxonomy and nutrition of this genus have been extensively studied, the habitat of these rare species has to date not been studied in detail. It was hypothesized that while the Nepenthes of Mount Kinabalu and Mount Tambuyukon are excluders of excess trace elements, soil chemistry is nevertheless a major driver for creating the specific habitats in which ultramafic edaphic endemic Nepenthes occur, and that this is reflected in vegetation physiognomy and co-occurring species composition as well as in the foliar chemistry of Nepenthes. The results show that the characteristics of the physical environment and soil chemistry ‘induces’ a vegetation physiognomy that varies among sites and produces a series of different niches that are colonised by different Nepenthes-species. Although other plant species associated with these niches do not directly influence the distributions of the Nepenthes-species, some are characteristic. The unusual ultramafic soil chemistry is not reflected in the foliar chemistry of Nepenthes and they appear to be ‘Excluders’ of potentially toxic soil trace element concentrations. The populations of Nepenthes burbidgeae, N. edwardsiana, N, rajah, N. villosa are small (in particular, N. burbidgeae) and these species are thus likely to be vulnerable to the potential effects of climate change-induced drought and fire.

Nutritional mutualisms of Nepenthes and Roridula

Nepenthes baramensis, a new species from peat swamp and heath forests in north-western Borneo, is described. It is distinguished from related species on the basis of its modified pitchers, which facilitate a facultative mutualistic interaction with Hardwicke’s Woolly Bat, Kerivoula hardwickii, which roosts in its pitchers and may provide the plant with a substantial proportion of its foliar nitrogen.

Ecological outsourcing: a pitcher plant benefits from transferring pre‐digestion of prey to a bat mutualist

Pitcher plants of the family Nepenthaceae are vines or subscandent shrubs which produce modified leaf organs that in most species serve to attract, trap, retain and digest animals for nutritional benefit. The sole genus within the family, Nepenthes, is abundant and diverse in Malesia. Previous taxonomic treatments of Nepenthes have relied almost entirely on the morphological features of the plants, with characteristics of the pitchers, inflorescences, leaf blades and indumentum being the most informative. Recent ecological research demonstrates that unique morphological characteristics and trap geometries provide useful taxonomic information, but this is often lost or obscured when specimens are prepared for herbaria by pressing them. In this paper, we demonstrate the value of ecological information in distinguishing between controversial montane Bornean taxa and provide a revised protocol for the collection and preparation of Nepenthes specimens, which is designed to maximise the amount of ecological information retained in herbarium material.

Nepenthes chaniana (Nepenthaceae), a new species from north-western Borneo

BackgroundThe Palaeotropical pitcher plant genus Nepenthes (Nepenthaceae) is characterized by specialized nutrient sequestration strategies, narrow endemism, and a patchy distribution in which vicariance is believed to have played a fundamental role.ScopeUsing recent studies of the effects of climate, soil type and vicariance, we review patterns of diversity and endemism in Nepenthes. First we consider how climate influences the geographical range of the genus and diversity of prey trapping mechanisms. Second, we examine edaphic influences, specifically the relationship between limestone and ultramafic soils and the obligate edaphic endemic Nepenthes that inhabit them. Third, we examine the role of vicariance, with regards to the patchy distribution of suitable habitats throughout Southeast Asia, and the passive dispersal mechanism of Nepenthes seeds.ConclusionsClimate is the principal determinant of variation in pitcher functional traits and in perhumid environments, may drive the evolution of alternative nutrient sequestration strategies. Although little is known about the ecophysiological relationships between soil type and obligate edaphic Nepenthes, ultramafic and limestone substrates may strongly influence vegetation physiognomy, creating a diversity of environmental niches that are exploited by specialized Nepenthes species. Finally, the complex geology and geography of the Malay Archipelago drives diversification through vicariance.

Nepenthes tenax C. Clarke & R. Kruger (Nepenthaceae), a new species from Cape York Peninsula, Queensland

Anthropogenic climate change is predicted to have profound effects on species distributions over the coming decades. In this paper, we used maximum entropy modelling (Maxent) to estimate the effects of projected changes in climate on extent of climatically-suitable habitat for two Nepenthes pitcher plant species in Borneo. The model results predicted an increase in area of climatically-suitable habitat for the lowland species Nepenthes rafflesiana by 2100; in contrast, the highland species Nepenthes tentaculata was predicted to undergo significant loss of climatically-suitable habitat over the same period. Based on the results of the models, we recommend that research be undertaken into practical mitigation strategies, as approximately two-thirds of Nepenthes are restricted to montane habitats. Highland species with narrow elevational ranges will be at particularly high risk, and investigation into possible mitigation strategies should be focused on them.