112 
Ganl. Bull. Singapore 70 (Suppl. 1) 2018 
Table 1. Mean temperature and humidity of the sampling plots. 
Site 
Humidity (Mean) 
Temperature 
(Mean)/°C 
Upper Swamp 1 
76.08 
29.46 
Upper Swamp 2 
78.58 
30.05 
Middle Swamp 1 
87.00 
28.05 
Middle Swamp 2 
90.13 
27.75 
Middle Swamp 3 
92.00 
26.20 
Middle Swamp 4 
90.83 
27.63 
Middle Swamp 5 
81.00 
29.51 
Middle Swamp 6 
85.38 
28.34 
Lower Swamp 1 
81.00 
30.25 
Lower Swamp 2 
89.00 
28.96 
Lower Swamp 3 
83.75 
28.70 
Lower Swamp 4 
86.13 
28.96 
Outskirt 1 
69.92 
32.10 
Outskirt 2 
80.50 
28.50 
Outskirt 3 
76.63 
32.19 
Cyclotus rostellatus (Pfeiffer, 1851), Fig. 2B 
Cyclotus rostellatus is one of the rarer land snails found in Nee Soon freshwater swamp 
forest. Restricted to undisturbed forested areas, this snail has only been recorded in 
Nee Soon since 1990. The shell has a short sutural tube present near the aperture which 
is believed to aid in respiration in moist environments (Ho, 1995). All specimens were 
observed in moist areas with dense canopy cover. 
Japonia ciliocinctum (Martens, 1865), Fig. 2C 
Japonia ciliocinctum is mostly to be found foraging in the depths of the freshwater 
swamp forest. The shell is dull brown in colour with a hairy periostracum along the 
periphery. It has been speculated that the hairy periostracum might facilitate movement 
in a moist environment by relieving surface tension (Pfenninger et al., 2005). However, 
the hairy periostracum falls off easily upon handling. All observed specimens were 
found in swampy areas with a dense canopy cover. 
Family ACHATINIDAE 
Achatina fulica Bowdich, 1822, Fig. 2D 
Achatinafulica is an invasive species originating from Africa and is commonly known 
as the Giant African Snail. In Nee Soon freshwater swamp forest shell heights of 7.5 
cm or more have been observed. It is commonly found in parks and degraded forest 
but rarely in undisturbed forest. Unfortunately, several specimens were recorded deep 
