Ladybird Beetles (Coleoptera: Coccinellidae) Present in Assam Agricultural University, Jorhat: Species Inventory with a Dichotomous Identification Key

Abstract

Background: Ladybird beetles (Coleoptera: Coccinellidae) are important components of agricultural ecosystems, and reliable species-level identification is necessary for their documentation. Aims: This study aimed to identify the coccinellid species occurring in the agricultural and horticultural ecosystems of Assam Agricultural University, Jorhat, and to develop a practical dichotomous identification key. Study Design:  Field survey with regular sampling. Place and Duration of Study: Agricultural and horticultural ecosystems of Assam Agricultural University, Jorhat from February to July 2025. Methodology: Adult coccinellid beetles were collected twice a week from the agricultural and horticultural ecosystems using sweep sampling and handpicking. Collected specimens were identified based on observed morphological characters, and a dichotomous key was developed for the recorded species. Results: In the present study, seven species of Coccinellidae, namely, Coelophora bissellata, Coccinella septempunctata, Coccinella transversalis, Cheilomenes sexmaculata, Micraspis univittata, Harmonia dimidiata and Illeis indica were identified and their detailed descriptions, along with an identification key, are given below. The findings may aid in subsequent studies on the distribution, ecology and biological-control potential of coccinellids in agricultural ecosystems of northeastern India. Conclusion: The study aims to provide a baseline inventory of the coccinellid species found at Assam Agricultural University, Jorhat, together with a practical morphology-based identification key. The key has been developed for preliminary identification of the species at the regional level, for species documentation, and to assist in biological control. Further surveys covering additional habitats, seasons and standardised sampling effort would be useful to obtain a more comprehensive assessment of coccinellid assemblages in the region.