<div>Background: Indragiri Hilir District has the most extensive rice harvest area and is the most significant contributor to rice production in Riau Province. Family Chalcididae is a parasitoid insect that can act as a biological agent to reduce pest attacks on rice. This research aimed to study the species diversity of Chalcididae on tidal swamp rice fields in Indragiri Hilir District. 
 
Methods: Sampling was carried out in two periods of rice planting. Samplings were conducted in 4 sub-districts of rice production centers, namely Batang Tuaka, Keritang, Reteh and Tembilahan Hulu, using three sampling techniques (i.e., insect net, malaise trap and yellow pan trap). Diversity index (H&rsquo;), Species richness index (d), Species Evenness index (J&rsquo;) and Similarity Index (Is) were calculated. 
 
Result: We found 127 individuals consisting of 5 genera and 11 species of Chalcididae were found in the four studied areas. Among them, Antrocephalus lugubris, A. maculipennis, Brachymeria excarinata, B. minuta and Dirhinus anthracia. B. excarinata and Antrocephalus sp. are reported as a new record to Indonesia and were found in all study locations. B. excarinata has the highest abundance of individuals. The shape of the landscape can influence the diversity index, species abundance and individual abundance of Chalcididae.</div>

Species Diversity and Composition of Chalcidids Wasps (Chalcidoidea: Hymenoptera) on Tidal Swamp Rice Field in Indragiri Hilir District, Indonesia