Abstract:
Ants are a very common and important biotic component in the environment which
can be found on every continent on earth except Antarctica. Three hundred and
forty-one valid ant species/subspecies belonging to 79 genera under 11 subfamilies
have been recorded in Sri Lanka, but very little is known about the ants of the
Eastern Province of the country. An ant survey in Ampara, which is one the largest
districts of the Eastern Province was conducted for the first time and the first ant
inventory of paddy fields of Sammanthurai was prepared. Sammanthurai in
Ampara District is located 4.8 km west of the Bay of Bengal coast and lies between
the towns of Ampara and Karaitivu along the A31 road. Worker ants of two
selected paddy fields in Sammanthurai were surveyed on the 8th of January, 12th
of March, 16th, and 17th of July by using honey baiting, soil sifting, and hand
collection. In each paddy field, two 100 m transects were laid using a nylon cord.
Twenty-five pieces of gauze (2 x 2 cm) with a drop of honey were placed at 4 m
intervals along each transect and ants were collected into bottles containing 70 %
ethanol after an hour. Soil sifting was conducted 1 m right to each transect and
twenty-five samples (approximately 10 x 10 x 10 cm) at 4 m intervals taken along
each transect were sifted using a sieve and white tray. All ants fallen into the white
tray were preserved as above. Along each transect, worker ants crawled on the
floor and the rice bushes were collected using paint brushes and a pair of fine
forceps. Honey baiting and hand collection caught worker ants of 4 subfamilies,
Dolichoderinae, Formicinae, Myrmicinae, and Ponerinae, and 14 genera and 14
species while soil sifting resulted in 3 subfamilies, Dolichoderinae, Formicinae and
Myrmicinae, 10 genera and 12 species. Overall worker ants of four subfamilies,
Dolichoderinae, Formicinae, Myrmicinae, and Ponerinae, 15 genera and 20
species were recorded and can be considered as a preliminary ant inventory of
paddy fields in Sammanthurai. Tapinoma pithecorum Seifert, 2022 was recorded
for the first time in Sri Lanka during this study.
