In 2001, Charles Clarke performed a cladistic analysis of the Nepenthes species of Sumatra and Peninsular Malaysia using 70 morphological characteristics of each taxon. The following is part of the resultant cladogram, showing "Clade 3", which comprises N. singalana and three other related species.[5]
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Meimberg, H. & G. Heubl 2006. Introduction of a nuclear marker for phylogenetic analysis of Nepenthaceae. Plant Biology8(6): 831–840. doi:10.1055/s-2006-924676
Meimberg, H., S. Thalhammer, A. Brachmann & G. Heubl 2006. Comparative analysis of a translocated copy of the trnK intron in carnivorous family Nepenthaceae. Molecular Phylogenetics and Evolution39(2): 478–490. doi:10.1016/j.ympev.2005.11.023
Renner, T. & C.D. Specht 2011. A sticky situation: assessing adaptations for plant carnivory in the Caryophyllales by means of stochastic character mapping. International Journal of Plant Sciences172(7): 889–901. doi:10.1086/660882
Rottloff, S., U. Müller, R. Kilper & A. Mithöfer 2009. Micropreparation of single secretory glands from the carnivorous plant Nepenthes. Analytical Biochemistry394(1): 135–137. doi:10.1016/j.ab.2009.07.013
Rottloff, S., R. Stieber, H. Maischak, F.G. Turini, G. Heubl & A. Mithöfer 2011. Functional characterization of a class III acid endochitinase from the traps of the carnivorous pitcher plant genus, Nepenthes. Journal of Experimental Botany62(13): 4639–4647. doi:10.1093/jxb/err173