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Ganl. Bull. Singapore 70 (Suppl. 1) 2018 
PCI 
Fig. 10. Plot results of the ordinary linear square test on environmental variables PCI to species 
diversity index (H’), with slope at -0.04, intercept 0.62. 
Discussion 
Biodiversity baselines for odonates of Nee Soon freshwater swamp forest 
Altogether, we recorded 49 species of 34 genera in 11 families for our current study. 
Relative species richness per survey site varied from two to 13, and mean abundance 
of odonate individuals recorded per survey site varied from three to 106. An updated 
species list of Nee Soon dragonflies is provided for future reference, with 67 species 
of 47 genera in 11 families, representing about half of all odonates ever recorded in 
Singapore. Among the eight sub-catchments, the three mid sub-catchments all show 
low abundance and species richness. This is followed by the two upper sub-catchments. 
The three low sub-catchments all had high abundance and species richness. Species 
richness ranges from 3.5 to 9.25 species/site with the highest species richness at Lower 
3 sub-catchment and the lowest at Mid 1 sub-catchment. 
Compared to historical records, the change in distribution of Prodasineura is 
quite remarkable. Murphy (1997: 343, Fig. 4) plotted records of the three Prodasineura 
species and commented that: “none of these have been found outside the CCNR 
