Insights into the morphometric and molecular characterisation of ber fruit fly (Carpomyia vesuviana Costa) infesting jujube ber, Ziziphus mauritiana (Lamk.)

<br><i>Carpomyia vesuviana</i> Costa, a fruit fly species, is a major pest affecting the jujube (Ber). This monophagous insect pest causes significant economic losses in regions where the jujube is cultivated. Hence, the present study was conducted to provide a detailed morphometric and molecular analysis of <i>C. vesuviana</i> across various Indian regions, specifically Tamil Nadu, Punjab, and Rajasthan. Morphometric measurements were conducted for various developmental stages, from the egg to adult. The overall mean length and width of the egg were 0.61 mm and 0.18 mm, respectively, and the fully grown maggot measured 6.19 mm (length) and 1.91 mm (width). The length and width of the prepupa and pupa were 7.67 mm and 1.64 mm, and 4.00 mm and 1.72 mm, respectively. The overall mean length of the female whole body and wing expanse measured 4.74 mm and 3.92 mm, respectively. The overall mean male whole body length and wing expanse were 4.19 mm and 3.56 mm, respectively. The results of the Principal Component Analysis (PCA) revealed that the maggot's length at different stages, pupa length, and egg width were the main contributors to the variability, particularly in the samples from Rajasthan. Additionally, the adult female fly's morphometric traits, such as the wing and thorax measurements, showed regional variations, with the PCA highlighting Punjab's alignment with larger head and abdomen traits. The molecular analysis based on PCR and sequencing of the COXI–COXII region confirmed the species identity. The nucleotide sequence of <i>C. vesuviana </i>from Tamil Nadu and Punjab was deposited in GenBank as PQ198003.1 and PQ198005.1 which had nearly 99% genetic similarity with two sequences NC_071721.1 (Beijing, China) and MT121231.1 (Beijing, China) submitted in the NCBI database. A phylogenetic analysis further demonstrated that the Tamil Nadu and Punjab populations were closely related to an Iranian sample, while samples from other countries, such as the <i>C. schineri</i> of the USA and <i>C. incompleta</i> of Iraq, exhibited higher genetic divergence. The findings underline both morphological and genetic variations within <i>C. vesuviana</i>, reflecting the geographical influence on the species development and evolution.