The specific name, kurochkini, honors the late Prof. Evgeny Kurochkin, a prominent paleontologist, for his contributions to the study of fossil birds.

IVPP V 17964 was collected at deposits near the Lamadong Town, Jianchang County of the Liaoning Province, from the Jiufotang Formation, dated to the Aptian stage of the Early Cretaceous, approximately 120.3 million years ago.

[1] The phylogenetic position of Longusunguis was explored by Wang et al. (2014) using a data matrix that includes 56 avialan taxa, scored based on 262 morphological traits.

Longusunguis was recovered as an advanced bohaiornithid, closely related to Bohaiornis and Parabohaiornis whose specimens were collected at nearby localities, also near the Lamadong Town.

Pengornis Eocathayornis Cathayornis Neuquenornis Gobipteryx Vescornis Eoalulavis Concornis Qiliania Eoenantiornis Shenqiornis Sulcavis Zhouornis Longusunguis Parabohaiornis Bohaiornis