Abstract  [Aim]  This study reports a new record of the genus Cobboldia in China. The oviposition habits of Cobboldia elephantis are documented; the condition of hatching is tested, and the morphology of the first-instar larvae is described, and compared with that of the genera Gasterophilus and Gyrostigma. [Methods]  Field observations were conducted to record the oviposition habits of C. elephantis. The conditions of hatching were tested in the laboratory environment. The morphology of the eggs and first-instar larvae was observed, and the diagnostic characters were photographed and described in detail. [Results]  In the field, C. elephantis lay eggs at the base of elephant tusks, the egg clusters were tightly packed, with the number on one tusk ranging from 56 to 385. The eggs of C. elephantis require water to hatch, and can hatch in 5 minutes at 35 ℃, which corresponds to the climate of the habitats of Asian elephants during our field study period between March to May. This hatching condition also aligns with the frequent bathing or mud-bathing behavior of Asian elephants to maintain moisture on their skin. The morphological features of the first-instar larvae of C. elephantis are obviously different from that of the known species of Gasterophilus and Gyrostigma, with two pairs of accessory mouthhooks on the outside of the mouthhooks, no sword-shaped labrum, the posterior spiracular that does not protrude from the body, and spines on the end of body. [Conclusion]  The records of the subfamily Gasterophilinae in China has increased to two genera, and the identification characteristics of the first-instar larvae of Cobboldia are clarified. Considering that these taxa are all pathogens myiasis in wild animals, this study also provides a practical method to monitor the infection of stomach bot flies for endangered animals such as Asian elephants as a protective measures.